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High frequency of EBV association and 30-bp deletion in the LMP-1 gene in CD56 lymphomas of the upper aerodigestive tract

Tai YC, Kim LH, Peh SC

Pathol. Int., 2004 Mar;54(3):158-66.
PMID: 14989738

Natural killer (NK)/T-cell lymphomas are frequently associated with Epstein-Barr virus (EBV), and usually lack TCR gene rearrangement. Studies from Asia have reported frequent deletion in the LMP-1 gene in EBV-associated nasopharyngeal carcinoma (NPC). The present study aims to investigate LMP-1 and TCRgamma gene status in upper aerodigestive tract lymphomas. A total of 43 cases were classified into T-, B-, and NK/T-cell tumors based on the phenotype expressions of CD3(+)/CD20(-)/CD56(-), CD3(-)/CD20(+)/CD56(-), and CD3(+)/CD20(-)/CD56(+), respectively. The presence of EBV in the tumor was confirmed by EBV early RNA-in situ hybridization. LMP-1 gene deletion and TCR gamma gene rearrangement were analyzed by polymerase chain reaction on paraffin-embedded tissues. There were 20 NK/T-, eight T-, and 15 B-cell phenotype lymphomas in the present series, and EBV was detected in 19 (95%), two (25%), and three (20%) cases in the respective groups. All EBV+ cases carried 30-bp deletion in the LMP-1 gene, and two of the NK/T-cell cases were infected by both the wild type and deleted strains. Five (25%) of the NK/T-cell phenotype lymphomas showed rearranged TCR gamma gene. The present study revealed a high frequency of EBV association, and a high frequency of 30-bp deletion in the LMP-1 gene in the virus in the present series of lymphoma. The NK/T-phenotype lymphomas are comprised of both NK-cell and cytotoxic T-lymphocyte-derived tumors.

Matched MeSH terms: T-Lymphocytes, Cytotoxic/pathology
Fulltext Basic fibroblast growth factor modulates cell cycle of human umbilical cord-derived mesenchymal stem cells

Ramasamy R, Tong CK, Yip WK, Vellasamy S, Tan BC, Seow HF

Cell Prolif, 2012 Apr;45(2):132-9.
PMID: 22309282 DOI: 10.1111/j.1365-2184.2012.00808.x

BACKGROUND: Mesenchymal stem cells (MSC) have great potential in regenerative medicine, immunotherapy and gene therapy due to their unique properties of self-renewal, high plasticity, immune modulation and ease for genetic modification. However, production of MSC at sufficient clinical scale remains an issue as in vitro generation of MSC inadequately fulfils the demand with respect to patients.
OBJECTIVES: This study has aimed to establish optimum conditions to generate and characterize MSC from human umbilical cord (UC-MSC).
MATERIALS AND METHODS: To optimize MSC population growth, basic fibroblast growth factor (bFGF) was utilized in culture media. Effects of bFGF on expansion kinetics, cell cycle, survival of UC-MSC, cytokine secretion, expression of early stem-cell markers and immunomodulation were investigated.
RESULTS: bFGF supplementation profoundly enhanced UC-MSC proliferation by reducing population doubling time without altering immunophenotype and immunomodulatory function of UC-MSC. However, cell cycle studies revealed that bFGF drove the cells into the cell cycle, as a higher proportion of cells resided in S phase and progressed into M phase. Consistent with this, bFGF was shown to promote expression of cyclin D proteins and their relevant kinases to drive UC-MSC to transverse cell cycle check points, thus, committing the cells to DNA synthesis. Furthermore, supplementation with bFGF changed the cytokine profiles of the cells and reduced their apoptotic level.
CONCLUSION: Our study showed that bFGF supplementation of UC-MSC culture enhanced the cells' growth kinetics without compromising their nature.

Matched MeSH terms: T-Lymphocytes/immunology
Fulltext Association of BRCA1- and BRCA2-deficiency with mutation burden, expression of PD-L1/PD-1, immune infiltrates, and T cell-inflamed signature in breast cancer

Wen WX, Leong CO

PLoS One, 2019;14(4):e0215381.
PMID: 31022191 DOI: 10.1371/journal.pone.0215381

Immune checkpoint inhibitors have demonstrated effective anti-tumour response in cancer types with high mutation burden (e.g. melanoma) and in subset of cancers with features of genomic instability (e.g. mismatch-repair deficiency). One possible explanation for this effect is the increased expression of immune checkpoint molecules and pre-existing adaptive immune response in these cancers. Given that BRCA1 and BRCA2 are integral in maintaining genomic integrity, we hypothesise that the inactivation of these genes may give rise to breast cancers with such immunogenic phenotype. Therefore, using two large series of publicly available breast cancer datasets, namely that from The Cancer Genome Atlas and Wellcome Trust Institute, we sought to investigate the association between BRCA1- and BRCA2-deficiency with features of genomic instability, expression of PD-L1 and PD-1, landscape of inferred tumour-infiltrating immune cells, and T-cell inflamed signature in breast cancers. Here, we report that BRCA1 and BRCA2-deficient breast cancers were associated with features of genomic instability including increased mutation burden. Interestingly, BRCA1-, but not BRCA2-, deficient breast cancers were associated with increased expression of PD-L1 and PD-1, higher abundance of tumour-infiltrating immune cells, and enrichment of T cell-inflamed signature. The differences in immunophenotype between BRCA1- and BRCA2-deficient breast cancers can be attributed, in part, to PTEN gene mutation. Therefore, features of genomic instability such as that mediated by BRCA1- and BRCA2- deficiency in breast cancer were necessary, but not always sufficient, for yielding T cell-inflamed tumour microenvironment, and by extension, predicting clinical benefit from immunotherapy.

Matched MeSH terms: Lymphocytes, Tumor-Infiltrating/immunology
Fulltext Reduced microbial diversity in adult survivors of childhood acute lymphoblastic leukemia and microbial associations with increased immune activation

Chua LL, Rajasuriar R, Azanan MS, Abdullah NK, Tang MS, Lee SC, et al.

Microbiome, 2017 03 20;5(1):35.
PMID: 28320465 DOI: 10.1186/s40168-017-0250-1

BACKGROUND: Adult survivors of childhood cancers such as acute lymphoblastic leukemia (ALL) have health problems that persist or develop years after cessation of therapy. These late effects include chronic inflammation-related comorbidities such as obesity and type 2 diabetes, but the underlying cause is poorly understood.
RESULTS: We compared the anal microbiota composition of adult survivors of childhood ALL (N = 73) with healthy control subjects (N = 61). We identified an altered community with reduced microbial diversity in cancer survivors, who also exhibit signs of immune dysregulation including increased T cell activation and chronic inflammation. The bacterial community among cancer survivors was enriched for Actinobacteria (e.g. genus Corynebacterium) and depleted of Faecalibacterium, correlating with plasma concentrations of IL-6 and CRP and HLA-DR+CD4+ and HLA-DR+CD8+ T cells, which are established markers of inflammation and immune activation.
CONCLUSIONS: We demonstrated a relationship between microbial dysbiosis and immune dysregulation in adult ALL survivors. These observations suggest that interventions that could restore microbial diversity may ameliorate chronic inflammation and, consequently, development of late effects of childhood cancer survivors.

Matched MeSH terms: CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes
Decrease of CD69 levels on TCR Vα7.2+CD4+ innate-like lymphocytes is associated with impaired cytotoxic functions in chronic hepatitis B virus-infected patients

Yong YK, Tan HY, Saeidi A, Rosmawati M, Atiya N, Ansari AW, et al.

Innate Immun, 2017 07;23(5):459-467.
PMID: 28606013 DOI: 10.1177/1753425917714854

Hepatitis B virus (HBV) infection is a major cause of chronic liver disease that may progress to liver cirrhosis and hepatocellular carcinoma. Host immune responses represent the key determinants of HBV clearance or persistence. Here, we investigated the role of the early activation marker, CD69 and effector cytokines, granzyme B (GrB) and IFN-γ in the exhaustion of innate-like TCR Vα7.2+CD4+T cells, in 15 individuals with chronic HBV (CHB) infection where six were HBV DNA+ and nine were HBV DNA-. The percentage of cytokine-producing T cells and MAIT cells were significantly perturbed in HBV patients relative to healthy controls (HCs). The intracellular expression of GrB and IFN-γ was significantly reduced in MAIT cells derived from HBV-infected patients as compared to HCs, and the levels correlated with the percentage and levels [mean fluorescence intensity (MFI)] of CD69 expression. The total expression of CD69 (iMFI) was lower in CHB patients as compared to HCs. The frequency of CD69+ cells correlated with the levels of cytokine expression (MFI), particularly in CHB patients as compared to HCs. In summary, the polyfunctionality of peripheral T cells was significantly reduced among CHB patients, especially in the TCR Vα7.2+CD4+T cells, and the levels of cytokine expression correlated with functional cytokine levels.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology*
Fulltext Development and immunogenic potentials of chitosan-saponin encapsulated DNA vaccine against avian infectious bronchitis coronavirus

Bande F, Arshad SS, Bejo MH, Omar AR, Moeini H, Khadkodaei S, et al.

Microb Pathog, 2020 Dec;149:104560.
PMID: 33068733 DOI: 10.1016/j.micpath.2020.104560

Infectious Bronchitis (IB) is an economically important avian disease that considerably threatens the global poultry industry. This is partly, as a result of its negative consequences on egg production, weight gain as well as mortality rate.The disease is caused by a constantly evolving avian infectious bronchitis virus whose isolates are classified into several serotypes and genotypes that demonstrate little or no cross protection. In order to curb the menace of the disease therefore, broad based vaccines are urgently needed. The aim of this study was to develop a recombinant DNA vaccine candidate for improved protection of avian infectious bronchitis in poultry. Using bioinformatics and molecular cloning procedures, sets of monovalent and bivalent DNA vaccine constructs were developed based on the S1 glycoprotein from classical and variants IBV strains namely, M41 and CR88 respectively. The candidate vaccine was then encapsulated with a chitosan and saponin formulated nanoparticle for enhanced immunogenicity and protective capacity. RT-PCR assay and IFAT were used to confirm the transcriptional and translational expression of the encoded proteins respectively, while ELISA and Flow-cytometry were used to evaluate the immunogenicity of the candidate vaccine following immunization of various SPF chicken groups (A-F). Furthermore, histopathological changes and virus shedding were determined by quantitative realtime PCR assay and lesion scoring procedure respectively following challenge of various subgroups with respective wild-type IBV viruses. Results obtained from this study showed that, groups vaccinated with a bivalent DNA vaccine construct (pBudCR88-S1/M41-S1) had a significant increase in anti-IBV antibodies, CD3+ and CD8+ T-cells responses as compared to non-vaccinated groups. Likewise, the bivalent vaccine candidate significantly decreased the oropharyngeal and cloacal virus shedding (p < 0.05) compared to non-vaccinated control. Chickens immunized with the bivalent vaccine also exhibited milder clinical signs as well as low tracheal and kidney lesion scores following virus challenge when compared to control groups. Collectively, the present study demonstrated that bivalent DNA vaccine co-expressing dual S1 glycoprotein induced strong immune responses capable of protecting chickens against infection with both M41 and CR88 IBV strains. Moreso, it was evident that encapsulation of the vaccine with chitosan-saponin nanoparticle further enhanced immune responses and abrogates the need for multiple booster administration of vaccine. Therefore, the bivalent DNA vaccine could serve as efficient and effective alternative strategy for the control of IB in poultry.

Matched MeSH terms: CD8-Positive T-Lymphocytes/immunology
Fulltext Induction of humoral and cell-mediated immune responses by hepatitis B virus epitope displayed on the virus-like particles of prawn nodavirus

Yong CY, Yeap SK, Goh ZH, Ho KL, Omar AR, Tan WS

Appl Environ Microbiol, 2015 Feb;81(3):882-9.
PMID: 25416760 DOI: 10.1128/AEM.03695-14

Hepatitis B virus (HBV) is a deadly pathogen that has killed countless people worldwide. Saccharomyces cerevisiae-derived HBV vaccines based upon hepatitis B surface antigen (HBsAg) is highly effective. However, the emergence of vaccine escape mutants due to mutations on the HBsAg and polymerase genes has produced a continuous need for the development of new HBV vaccines. In this study, the "a" determinant within HBsAg was displayed on the recombinant capsid protein of Macrobrachium rosenbergii nodavirus (MrNV), which can be purified easily in a single step through immobilized metal affinity chromatography (IMAC). The purified protein self-assembled into virus-like particles (VLPs) when observed under a transmission electron microscope (TEM). Immunization of BALB/c mice with this chimeric protein induced specific antibodies against the "a" determinant. In addition, it induced significantly more natural killer and cytotoxic T cells, as well as an increase in interferon gamma (IFN-γ) secretion, which are vital for virus clearance. Collectively, these findings demonstrated that the MrNV capsid protein is a potential carrier for the HBV "a" determinant, which can be further extended to display other foreign epitopes. This paper is the first to report the application of MrNV VLPs as a novel platform to display foreign epitopes.

Matched MeSH terms: T-Lymphocytes/immunology
Fulltext HIV/Human herpesvirus co-infections: Impact on tryptophan-kynurenine pathway and immune reconstitution

Yap SH, Abdullah NK, McStea M, Takayama K, Chong ML, Crisci E, et al.

PLoS One, 2017;12(10):e0186000.
PMID: 29016635 DOI: 10.1371/journal.pone.0186000

BACKGROUND: Co-infections with human herpesvirus (HHV) have been associated with residual chronic inflammation in antiretroviral (ART)-treated human immunodeficiency virus (HIV)-infected individuals. However, the role of HHV in modulating the tryptophan-kynurenine pathway and clinical outcomes in HIV-infected individuals is poorly understood. Thus, we investigated the seroprevalence of four common HHVs among treated HIV-infected participants and their impact on kynurenine/tryptophan (K/T) ratio and long-term CD4 T-cell recovery in HIV/HHV co-infected participants.
METHOD: In this cross-sectional study, HIV-infected participants receiving suppressive ART for a minimum of 12 months were recruited from the University Malaya Medical Centre (UMMC), Malaysia. Stored plasma was analyzed for CMV, VZV, HSV-1 and HSV-2 IgG antibody levels, immune activation markers (interleukin-6, interferon-γ, neopterin and sCD14), kynurenine and tryptophan concentrations. The influence of the number of HHV co-infection and K/T ratio on CD4 T-cell recovery was assessed using multivariate Poisson regression.
RESULTS: A total of 232 HIV-infected participants were recruited and all participants were seropositive for at least one HHV; 96.1% with CMV, 86.6% with VZV, 70.7% with HSV-1 and 53.9% with HSV-2. K/T ratio had a significant positive correlation with CMV (rho = 0.205, p = 0.002), VZV (rho = 0.173, p = 0.009) and a tendency with HSV-2 (rho = 0.120, p = 0.070), with CMV antibody titer demonstrating the strongest modulating effect on K/T ratio among the four HHVs assessed in SOM analysis. In multivariate analysis, higher K/T ratio (p = 0.03) and increasing number of HHV co-infections (p<0.001) were independently associated with poorer CD4 T-cell recovery following 12 months of ART initiation.
CONCLUSION: Multiple HHV co-infections are common among ART-treated HIV-infected participants in the developing country setting and associated with persistent immune activation and poorer CD4 T-cell recovery.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology
Fulltext PIP4Ks impact on PI3K, FOXP3, and UHRF1 signaling and modulate human regulatory T cell proliferation and immunosuppressive activity

Poli A, Abdul-Hamid S, Zaurito AE, Campagnoli F, Bevilacqua V, Sheth B, et al.

Proc Natl Acad Sci U S A, 2021 08 03;118(31).
PMID: 34312224 DOI: 10.1073/pnas.2010053118

Regulatory T cells (Tregs) play fundamental roles in maintaining peripheral tolerance to prevent autoimmunity and limit legitimate immune responses, a feature hijacked in tumor microenvironments in which the recruitment of Tregs often extinguishes immune surveillance through suppression of T-effector cell signaling and tumor cell killing. The pharmacological tuning of Treg activity without impacting on T conventional (Tconv) cell activity would likely be beneficial in the treatment of various human pathologies. PIP4K2A, 2B, and 2C constitute a family of lipid kinases that phosphorylate PtdIns5P to PtdIns(4,5)P 2 They are involved in stress signaling, act as synthetic lethal targets in p53-null tumors, and in mice, the loss of PIP4K2C leads to late onset hyperinflammation. Accordingly, a human single nucleotide polymorphism (SNP) near the PIP4K2C gene is linked with susceptibility to autoimmune diseases. How PIP4Ks impact on human T cell signaling is not known. Using ex vivo human primary T cells, we found that PIP4K activity is required for Treg cell signaling and immunosuppressive activity. Genetic and pharmacological inhibition of PIP4K in Tregs reduces signaling through the PI3K, mTORC1/S6, and MAPK pathways, impairs cell proliferation, and increases activation-induced cell death while sparing Tconv. PIP4K and PI3K signaling regulate the expression of the Treg master transcriptional activator FOXP3 and the epigenetic signaling protein Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1). Our studies suggest that the pharmacological inhibition of PIP4K can reprogram human Treg identity while leaving Tconv cell signaling and T-helper differentiation to largely intact potentially enhancing overall immunological activity.

Matched MeSH terms: T-Lymphocytes, Regulatory/physiology*
Serum folate concentration, cognitive impairment, and DNA damage among elderly individuals in Malaysia

Lee LK, Shahar S, Rajab N

Nutr Res, 2009 May;29(5):327-34.
PMID: 19555814 DOI: 10.1016/j.nutres.2009.05.006

The notion that dietary factors affect cognitive function and subsequently the risk of dementia has increased over the years from a global viewpoint. Because low folate intake has been described to impair cognitive function, we tested the hypothesis that low serum folate concentration is associated with cognitive impairment and an attenuated increase in DNA damage. We investigated the relationship between serum folate concentration, cognitive impairment, and DNA damage among elderly people attending health clinics in Klang Valley, an urban area in Malaysia. Two hundred thirty-two participants, composed of 115 men (49.6%) and 117 women (50.4%), were involved; none of the patients were diagnosed with neuropsychiatric problems, nor where they terminally ill. Sociodemography and health variables were assessed through face-to-face interview. Cognitive impairment review was conducted through an Elderly Cognitive Assessment Questionnaire. The estimation of dietary intake, serum folate concentration, and DNA damage was individually analyzed using validated Dietary History Questionnaires, immunoassay methods, and an Alkaline Comet Assay study (10 mL of peripheral venous blood), respectively. Results indicated that more men had cognitive impairment (33.0%) and DNA damage (27.0% for percentage DNA in tail, 22.6% tail moment) compared with women (25.6%, 15.4%, and 15.4%, respectively) (P < .05 for all parameters), recording an average folate deficiency value of 13.9% (0.2% higher than women). Multivariate binary logistic regression analysis outlined the association of cognitive impairment with older age (odds ratio [OR], 2.74; 95% confidence interval [CI], 1.35-5.57), smoking habits (OR, 5.12; 95% CI, 2.48-10.57), poor serum folate concentration (OR, 3.46; 95% CI, 1.26-9.52), and DNA damage (percentage DNA in tail) (OR, 13.70; 95% CI, 1.36-138.29). In conclusion, this study highlighted the important role of serum folate concentration for cognitive function and provided a concise picture regarding the elevated levels of oxidative DNA damage in peripheral lymphocytes.

Matched MeSH terms: Lymphocytes
Enhancement of immune response against Mycobacterium tuberculosis HspX antigen by incorporation of combined molecular adjuvant (CASAC)

Lew MH, Norazmi MN, Tye GJ

Mol Immunol, 2020 Jan;117:54-64.
PMID: 31739193 DOI: 10.1016/j.molimm.2019.10.023

Tuberculosis (TB) is one of the deadliest human diseases worldwide caused by mycobacterial infection in the lung. Bacillus Calmette-Guerin (BCG) vaccine protects against disseminated TB in children, but its effectiveness is still questionable due to highly variable protections in adolescence and elderly individuals. Targeting the latency M.tb antigen is a recent therapeutic approach to eradicate dormant pathogen that could possibly lead to disease activation. In this study, we aimed to potentiate immune responses elicited against 16 kDa α-crystalline (HspX) tuberculosis latency antigen by incorporation of Combined Adjuvant for Synergistic Activation of Cellular immunity (CASAC). Histidine-tagged recombinant HspX protein was initially produced in Escherichia coli and purified using Ni-NTA chromatography. To evaluate its adjuvanticity, C57BL/6 mice (n = 5) were initially primed and intradermally immunised in 2-weeks interval for 4 rounds with recombinant HspX, formulated with and without CASAC. Humoral and cell-mediated immune responses elicited against HspX antigen were evaluated using ELISA and Flow Cytometry. Our findings showed that CASAC improved humoral immunity with increased antigen-specific IgG1 and IgG2a antibody response. Stronger CD8+ and Th1-driven immunity was induced by CASAC formulation as supported by elevated level of IFN-γ, TNF-α, IL-12 and IL-17A; and with low IL-10 secretion. Interestingly, adjuvanted HspX vaccine triggered a higher percentage of effector memory T-cell population than those immunised with unadjuvanted vaccine. In conclusion, CASAC adjuvant has great potential to enhance immunogenicity elicited against HspX antigen, which could be an alternative regimen to improve the efficacy of future therapeutic vaccine against Mycobacterium tuberculosis.

Matched MeSH terms: CD8-Positive T-Lymphocytes
Optic Nerve Infiltration in Systemic Metastatic Retinal Lymphoma (SMRL): Multimodal Imaging and Challenges in Diagnosis

Mohd Fauzi Yap MFB, Mohd Zain A, Tumain NR, Palaniappan S, Nasaruddin RA, Md Din N

Ocul Immunol Inflamm, 2020 Sep 24.
PMID: 32967510 DOI: 10.1080/09273948.2020.1800050

A 45-year-old man was diagnosed with diffuse large B-cell lymphoma stage IV which was confirmed by celiac lymph node biopsy. He subsequently completed six cycles of R-CHOP chemotherapy. Six months later, he presented with panuveitis OU with positive relative afferent pupillary defect OD. OCT revealed hyper-reflective lesions and irregularity of the retinal pigment epithelium OU. Fundus fluorescein angiogram shows hyper-auto fluorescence and granular changes on the retina. A month later, he developed swollen optic disc OD and hemorrhagic retinitis OU and treated as presumed CMV retinitis. Anti-TB was started after a positive Mantoux test. He finally consented for a vitreous biopsy which showed atypical lymphoid cells highly suggestive for vitreoretinal lymphoma and subsequently received intravitreal methotrexate OU.
CONCLUSION: Optic nerve infiltration in systemic metastatic retinal lymphoma may have initial occult signs but with profound visual loss. Ocular infections like CMV retinitis and tuberculosis may mask and delay the diagnosis in immunocompromised patients.

Matched MeSH terms: Lymphocytes
In vitro characterization of chicken bone marrow-derived dendritic cells following infection with very virulent infectious bursal disease virus

Yasmin AR, Yeap SK, Tan SW, Hair-Bejo M, Fakurazi S, Kaiser P, et al.

Avian Pathol, 2015;44(6):452-62.
PMID: 26305169 DOI: 10.1080/03079457.2015.1084997

Infectious bursal disease is caused by infectious bursal disease virus (IBDV), an immunosuppressive virus that targets immune cells such as B cells and macrophages. However, the involvement of dendritic cells (DCs) during IBDV infection is not well understood. In this study the in vitro effects of live and inactivated very virulent IBDV (vvIBDV) UPM0081 on bone marrow-derived DCs (BM-DC) were characterized and compared with BM-DC treated with lipopolysaccharide (LPS). Morphologically, BM-DC treated with LPS and vvIBDV showed stellate shape when compared to immature BM-DC. In addition, LPS-treated and both live and inactivated vvIBDV-infected BM-DC expressed high levels of double positive CD86 and major histocompatibility complex class II antigens (>20%). vvIBDV-infected BM-DC showed significantly higher numbers of apoptotic cells compared to LPS. Replication of vvIBDV was detected in the infected BM-DC as evidenced by the increased expression of VP3 and VP4 IBDV antigens based on flow cytometry, real-time polymerase chain reaction and immunofluorescence tests. Levels of different immune-related genes such as interleukin-1β (IL-1β), CXCLi2 (IL-8), IL-18, interferon gamma (IFN-γ, IL-12α, CCR7 and Toll-like receptor-3 (TLR3) were measured after LPS and vvIBDV treatments. However, marked differences were noticed in the onset and intensity of the gene expression between these two treatment groups. LPS was far more potent than live and inactivated vvIBDV in inducing the expression of IL-1β, IL-18 and CCR7 while expression of Th1-like cytokines, IFN-γ and IL-12α were significantly increased in the live vvIBDV treatment group. Meanwhile, the expression of TLR3 was increased in live vvIBDV-infected BM-DC as compared to control. Inactivated vvIBDV-treated BM-DC failed to stimulate IFN-γ, IL-12α and TLR3 expressions. This study suggested that BM-DC may serve as another target cells during IBDV infection which require further confirmation via in vivo studies.

Matched MeSH terms: B-Lymphocytes
Fulltext Mucosal-associated invariant T cell alterations during the development of human type 1 diabetes

Gazali AM, Schroderus AM, Näntö-Salonen K, Rintamäki R, Pihlajamäki J, Knip M, et al.

Diabetologia, 2020 11;63(11):2396-2409.
PMID: 32880687 DOI: 10.1007/s00125-020-05257-7

AIMS/HYPOTHESIS: Mucosal-associated invariant T (MAIT) cells are innate-like T cells that recognise derivatives of bacterial riboflavin metabolites presented by MHC-Ib-related protein 1 (MR1) molecules and are important effector cells for mucosal immunity. Their development can be influenced by the intestinal microbiome. Since the development of type 1 diabetes has been associated with changes in the gut microbiome, this can be hypothesised to lead to alterations in circulating MAIT cells. Accordingly, peripheral blood MAIT cell alterations have been reported previously in patients with type 1 diabetes. However, a comprehensive analysis of the frequency and phenotype of circulating MAIT cells at different stages of type 1 diabetes progression is currently lacking.
METHODS: We analysed the frequency, phenotype and functionality of peripheral blood MAIT cells, as well as γδ T cells, invariant natural killer T (iNKT) cells and natural killer (NK) cells with flow cytometry in a cross-sectional paediatric cohort (aged 2-15) consisting of 51 children with newly diagnosed type 1 diabetes, 27 autoantibody-positive (AAb+) at-risk children, and 113 healthy control children of similar age and HLA class II background. The frequency of MAIT cells was also assessed in a separate cross-sectional adult cohort (aged 19-39) of 33 adults with established type 1 diabetes and 37 healthy individuals of similar age.
RESULTS: Children with newly diagnosed type 1 diabetes displayed a proportional increase of CD8-CD27- MAIT cells compared with healthy control children (median 4.6% vs 3.1% of MAIT cells, respectively, p = 0.004), which was associated with reduced expression of C-C chemokine receptor (CCR)5 (median 90.0% vs 94.3% of MAIT cells, p = 0.02) and β7 integrin (median 73.5% vs 81.7% of MAIT cells, p = 0.004), as well as decreased production of IFN-γ (median 57.1% vs 69.3% of MAIT cells, p = 0.04) by the MAIT cells. The frequency of MAIT cells was also decreased in AAb+ children who later progressed to type 1 diabetes compared with healthy control children (median 0.44% vs 0.96% of CD3+ T cells, p = 0.04), as well as in adult patients with a short duration of type 1 diabetes (less than 6 years after diagnosis) compared with control individuals (median 0.87% vs 2.19% of CD3+ T cells, p = 0.007). No alterations in γδ T cell, iNKT cell or NK cell frequencies were observed in children with type 1 diabetes or in AAb+ children, with the exception of an increased frequency of IL-17A+ γδ T cells in children with newly diagnosed diabetes compared with healthy control children (median 1.58% vs 1.09% of γδ T cells, p = 0.002).
CONCLUSIONS/INTERPRETATION: Changes in the frequency and phenotype of circulating MAIT cells were detectable before, at the onset and after diagnosis of type 1 diabetes in cross-sectional cohorts. Our results suggest a possible temporal association between peripheral blood MAIT cell alterations and the clinical onset of type 1 diabetes. Graphical abstract.

Matched MeSH terms: CD8-Positive T-Lymphocytes
Synthesis and study of anti-HIV-1 RT activity of 5-benzoyl-4-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-2-one derivatives

Chander S, Tang CR, Al-Maqtari HM, Jamalis J, Penta A, Hadda TB, et al.

Bioorg Chem, 2017 06;72:74-79.
PMID: 28371664 DOI: 10.1016/j.bioorg.2017.03.013

In the present study, a series of fourteen 5-benzoyl-4-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-2-one derivatives were designed, synthesized and characterized by appropriate spectral analysis. Further, titled compounds were in-vitro screened against wild HIV-1 RT enzyme using ELISA based colorimetric assay, in which four compounds significantly inhibited the RT activity with IC50≤25µM. Moreover, two significantly active compounds of the series, A10 and A11 exhibited IC50 values 8.62 and 6.87µM respectively, during the in-vitro assay. Structure Activity Relationship (SAR) studies were performed for the synthesized compounds in order to estimate the effect of substitution pattern on the RT inhibitory potency. The cytotoxicity of the synthesized compounds was evaluated against T lymphocytes. Further, putative binding modes of the significantly active (A11) and the least active (A4) compounds with wild HIV-1 RT were also investigated using docking studies.

Matched MeSH terms: CD4-Positive T-Lymphocytes
Fulltext Polymerase chain reaction analysis as a rapid screening test for diagnosis of fragile x syndrome

Phan, CL, Zubaidah, Z., Gregory, A.R.A., Ten, SK, Kamariah, M.N., Thilagavathi, S., et al.

Medicine & Health, 2006;1(1):36-44.
MyJurnal

Fragile X syndrome is a result of an unstable expansion of (CGG)n trinucleotide sequences in the FMR-1 (Fragile X Mental Retardation 1) gene site at Xq27. In a normal person, n ranges from 6 to 40 repeats with an average of 30 repeats, whereas in a mutated FMR1 gene the sequence is repeated several times over (stuttering gene). Full mutation occurs when n equals 200 repeats or more. Where n equals 50 to 200 repeats, it is a premutation. Fragile X occurs when the FMR-1 gene is unable to make normal amounts of usable Fragile X Mental Retardation Protein, or FMRP. The amount of FMRP in the body is one factor that determines the severity of the Fragile X syndrome. A person with nearly normal levels of FMRP usually has mild or no symptoms, while a person with very little or no normal FMRP has more severe symptoms. The mechanism for the role of the FMRP gene is still being researched upon. However, it has been observed that large numbers of repeats (more than 200) inactivates the gene through a process of methylation and when the gene is inactivated, the cell may make little or none of the needed FMRP. Inheritance is X-linked with reduced penetrance and the frequency of occurrence goes up through generations. The phenotypic manifestations of fragile-X syndrome vary and are largely dependent on the size of the mutation or premutation. The identification of the fragile site on G banded metaphases is a time consuming and delicate process requiring experience and skill, however, molecular diagnosis using DNA analysis and Southern blotting, even though expensive, is more specific in determining the presence or absence of the gene. This study was aimed to establish a rapid polymerase chain reaction (PCR) based - touch down PCR, as a screening method for fragile X syndrome. A total of six cases were analysed. Of these, one was a known case of Fragile X (T1) diagnosed by conventional cytogenetics, two were from the latter’s family members namely, his mother (T2) and father (T3), and the other two (T4 and T5) were randomly selected from patients presenting with dysmorphic features and delayed development respectively. One normal control (TC) was included. Cytogenetic analyses for detection of the fragile site was carried out in all cases. Two culture systems were used, namely the synchronised lymphocyte culture and the folate - thymidine deficient culture. Stained metaphases from the fragile X cultures were screened for the presence of the fragile site on the X chromosome. G-banded karyotyping was done using an image analyser to exclude presence of chromosomal abnormalities. DNA was extracted from these samples and amplified by touch-down PCR. Cytogenetic analysis revealed a folate-sensitive fragile site in the affected male, but none in the other five samples. G-banded karyotyping exhibited no additional chromosomal abnormalities. All extracted DNA samples were successfully amplified. Five of the samples showed presence of the product at the expected band at 552bp, excluding the presence of an expansion of CGG segment of the FMR-1 gene. The absence of a band in an affected individual, suggested a fully mutated allele of FRAXA (Folate Sensitive Fragile Site at Xq28). We succeeded in establishing a slightly modified touch-down PCR analysis. Our study indicates that PCR testing offers a rapid and specific method for screening of normal allele and full mutation of the fragile X gene. We suggest this technique to be applied as a complementary tool for cytogenetic analysis to detect the FRAXA gene.

Matched MeSH terms: Lymphocytes
Fulltext Association between oxidative DNA damage, fruits and vegetables intake with breast cancer: a preliminary study in Klang Valley

Suzana Shahar, Kim, Tiu Teng, Nor Fadilah Rajab, Fatimah Arshad

Jurnal Sains Kesihatan Malaysia, 2008;6(1):61-77.
MyJurnal

A preliminary study was conducted to determine the level of oxidative DNA damage, fruits and vegetables intake among 50 breast cancer patients (cases) as compared to 50 healthy women (controls) with no known medical history of breast cancer in Klang Valley. Both groups were matched for age and ethnicity. Data on socio-demographic, health status and medical history, fruits and vegetables intake, and supplements intake were obtained through an interviewbased questionnaire. Anthropometry measurements included weight, height, and waist and hip circumference were also carried out on subjects. A total of 3mL fasting venous blood was drawn to assess lymphocytes oxidative DNA damage using Alkaline Comet Assay. Results indicated that the mean intake of fruits and vegetables was lower in cases (4.09 ± 1.17 servings/d) than controls (4.77 ± 0.90 servings/d)(p < 0.05) The intake of fruits and vegetables from family groups of solanaceae, myrtaceae, caricaceae, apiaceae, brinjal, rutaceae, broccoli, orange, carrot, watermelon were 0.5 - 1 servings/week significantly higher among controls as compared to cases (p < 0.05 for all parameters). However, the intake of fruits from rosaceae family and apple was higher among controls than cases (p < 0.05). The estimated intake of ß-carotene, carotenoids, vitamin A, vitamin C (p < 0.001), a-carotene and lycopene (p < 0.05) from fruits and vegetables were higher among controls than cases. Mean DNA damage level of cases (4.55 ± 1.78 % DNA in tail, %TD; 0.35 ± 0.21 tail moment, TM) were 3.5 and 3.9 times higher than the value of controls (1.3 ± 0.70% TD; 0.09 ± 0.09 TM) (p < 0.001) and the damage increased with higher values of waist hip ratio (% TD, r = 0.396, p < 0.05; TM, r = 0.349, p < 0.05) and waist circumference (% TD, r = 0.334, p < 0.05; TM, r = 0.360, p < 0.05). There was an inverse relationship between oxidative DNA damage with intake of total fruits and vegetables, cauliflowers and water convolvulus and also consumption from rutaceae and solanaceae families. Similar trend was noted for estimated intake of vitamin A, carotenoids, vitamin C, ß-carotene and lycopene. In conclusion, the intake of fruits and vegetables of five servings/d and the consumption of specific families and types of fruits and vegetables might protect against oxidative DNA damage and further reduce breast cancer risk.

Matched MeSH terms: Lymphocytes
Fulltext Differential expression patterns of leukaemia associated genes in leukaemia cell lines compared to healthy controls

Ang Pei-Shen, Rajesh Ramasamy, Noor Hamidah Hussin, Cheong Soon-Keng, Seow Heng-Fong, Maha Abdullah

Malaysian Journal of Medicine and Health Sciences, 2016;12(1):0-0.
MyJurnal

Introduction: The phenotype and genotype of cancer cells portray hallmarks of cancer which may
have clinical value. Cancer cell lines are ideal models to study and confirm these characteristics. We
previously established two subtracted cDNA libraries with differentially expressed genes from an
acute myeloid leukaemia patient with poor prognosis (PP) and good prognosis (GP). Objective: To
compare gene expression of the leukaemia associated genes with selected biological characteristics
in leukaemia cell lines and normal controls. Methodology: Expression of 28 PP genes associated
with early fetal/embryonic development, HOX-related genes, hematopoiesis and aerobic glycolysis/
hypoxia genes and 36 GP genes involved in oxidative phosphorylation, protein synthesis, chromatin
remodelling and cell motility were examined in B-lymphoid (BV173, Reh and RS4;11) and myeloid
(HL-60, K562) leukaemia cell lines after 72h in culture as well as peripheral blood mononuclear cells
from healthy controls (N=5) using semi-quantitative polymerase chain reaction (PCR) method. Cell
cycle profiles were analysed on flow cytometry while MTT cytotoxicity assay was used to determine
drug resistance to epirubicin. Results: Genes expressed significantly higher in B-lymphoid leukaemia
cell lines compared to healthy controls were mostly of the GP library i.e. oxidative phosphorylation
(3/10), protein synthesis (4/11), chromatin remodelling (3/3) and actin cytoskeleton genes (1/5). Only
two genes with significant difference were from the PP library. Cancer associated genes, HSPA9 and
PSPH (GP library) and BCAP31 (PP library) were significantly higher in the B-lymphoid leukemia cell
lines. No significant difference was observed between myeloid cell lines and healthy controls. This
may also be due heterogeneity of cell lines studied. PBMC from healthy controls were not in cell cycle.
G2/M profiles and growth curves showed B-lymphoid cells just reaching plateau after 72 hour culture
while myeloid cells were declining. IC50 values from cytotoxicity assay revealed myeloid cell lines had
an average 13-fold higher drug resistance to epirubicin compared to B-lymphoid cell lines. Only CCL1,
was expressed at least two-fold higher in myeloid compared to B-lymphoid cell lines. In contrast,
MTRNR2, EEF1A1, PTMA, HLA-DR, C6orf115, PBX3, ENPP4, SELL, and IL3Ra were expressed
more than 2-fold higher in B-lymphoid compared to myeloid cell lines studied here. Conclusion: Thus,
B-lymphoid leukaemia cell lines here exhibited active, proliferating characteristics closer to GP genes.
Higher expression of several genes in B-lymphoid compared to myeloid leukaemia cell lines may be
useful markers to study biological differences including drug resistance between lineages.

Matched MeSH terms: Lymphocytes
Investigations for the Possible Use of a Monoclonal Antibody Produced against Strongyloides ratti Antigen as an Immunodiagnostic Reagent for Active Strongyloidiasis

Mahmuda A, Bande F, Abdulhaleem N, Abd Majid R, Awang Hamat R, Omar Abdullah W, et al.

Iran J Parasitol, 2018 8 3;13(2):204-214.
PMID: 30069204

Background: Currently, most of the available serological diagnostic kits for strongyloidiasis are based on the use of the crude antigens of Strongyloides ratti, which are good, but with less sensitivity towards the infection. Hence, this study aimed to produce and evaluate monoclonal antibody for detecting soluble parasite antigen in animal sera.
Methods: The study was conducted in the Department of Medical Microbiology and Parasitology, University Putra Malaysia in 2014-2017. Saline extract protein from the infective larvae of S. ratti was used to immunize BALB/c mice and subsequent fusion of the B-cells with myeloma cells (SP2/0) using 50% PEG. The hybridomas were cultured in HAT medium and cloned by limiting dilutions. Positive hybrids were screened by indirect ELISA. The ascites fluid from the antibody-secreting hybridoma was purified and the MAb was characterized by western-blots and evaluated in sandwich ELISA for reactivity against the homologous and heterologous antigens.
Results: An IgG1 that recognizes a 30 and 34 kDa protein bands was obtained. The MAb was recognized by all S. ratti-related antigens and cross-reacted with only Toxocara canis antigens in both assays. The minimum antigen detection limit was found to be 5 ng/ml. All antibody-positive rat and dog sera evaluated have shown antigen-positive reactions in Sandwich-ELISA.
Conclusion: The MAb produced, was able to detect antigens in strongyloidiasis and toxocariasis in animal models and may also be useful for the serological detection of active strongyloidiasis and visceral toxocariasis in human sera.

Matched MeSH terms: B-Lymphocytes
Fulltext CD3+CD4+gp130+ T Cells Are Associated With Worse Disease Activity in Systemic Lupus Erythematosus Patients

Mohd Shukri ND, Farah Izati A, Wan Ghazali WS, Che Hussin CM, Wong KK

Front Immunol, 2021;12:675250.
PMID: 34149710 DOI: 10.3389/fimmu.2021.675250

The receptors for IL-35, IL-12Rβ2 and gp130, have been implicated in the inflammatory pathophysiology of autoimmune diseases. In this study, we set out to investigate the serum IL-35 levels and the surface levels of IL-12Rβ2 and gp130 in CD3+CD4+, CD3+CD4─ and CD3─CD4─ lymphocyte subpopulations in systemic lupus erythematosus (SLE) patients (n=50) versus healthy controls (n=50). The potential T cell subsets associated with gp130 transcript (i.e. IL6ST) expression in CD4+ T cells of SLE patients was also examined in publicly-available gene expression profiling (GEP) datasets. Here, we report that serum IL-35 levels were significantly higher in SLE patients than healthy controls (p=0.038) but it was not associated with SLEDAI-2K scores. The proportions of IL-12Rβ2+ and gp130+ cells in SLE patients did not differ significantly with those of healthy controls in all lymphocyte subpopulations investigated. Essentially, higher SLEDAI-2K scores were positively correlated with increased proportion of gp130+ cells, but not IL-12Rβ2+ cells, on CD3+CD4+ T cells (r=0.425, p=0.002, q=0.016). Gene Set Enrichment Analysis (GSEA) of a GEP dataset of CD4+ T cells isolated from SLE patients (n=8; GSE4588) showed that IL6ST expression was positively associated with genes upregulated in CD4+ T cells vs myeloid or B cells (q<0.001). In an independent GEP dataset of CD4+ T cells isolated from SLE patients (n=9; GSE1057), IL6ST expression was induced upon anti-CD3 stimulation, and that Treg, TCM and CCR7+ T cells gene sets were significantly enriched (q<0.05) by genes highly correlated with IL6ST expression (n=92 genes; r>0.75 with IL6ST expression) upon anti-CD3 stimulation in these SLE patients. In conclusion, gp130 signaling in CD3+CD4+ T cell subsets may contribute to increased disease activity in SLE patients, and it represents a promising therapeutic target for inhibition in the disease.

Matched MeSH terms: T-Lymphocytes, Regulatory

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