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  1. Vimali J, Yong YK, Murugesan A, Govindaraj S, Raju S, Balakrishnan P, et al.
    Viral Immunol, 2024 Jun;37(5):240-250.
    PMID: 38808464 DOI: 10.1089/vim.2024.0007
    Human pegivirus (HPgV) appears to alter the prognosis of HIV disease by modulating T cell homeostasis, chemokine/cytokine production, and T cell activation. In this study, we evaluated if HPgV had any 'favorable' impact on the quantity and quality of T cells in HIV-infected individuals. T cell subsets such as CD4lo, CD4hi, and CD8+ T cells, CD4+ MAIT cells, CD8+ MAIT cells, follicular helper T (TFH) cells, and follicular cytotoxic T (TFC) cells were characterized based on the expression of markers associated with immune activation (CD69, ICOS), proliferation (ki67), cytokine production (TNF-α, IFN-γ), and exhaustion (PD-1). HIV+HPgV+ individuals had lower transaminase SGOT (liver) and GGT (biliary) in the plasma than those who were HPgV-. HIV/HPgV coinfection was significantly associated with increased absolute CD4+ T cell counts. HIV+HPgV+ and HIV+HPgV- individuals had highly activated T cell subsets with high expression of CD69 and ICOS on bulk CD4+ and CD8+ T cells, CD4+ MAIT cells, CD8+ MAIT cells, and CXCR5+CD4+ T cells and CXCR5+CD8+ T cells compared with healthy controls. Irrespective of immune activation markers, these cells also displayed higher levels of PD-1 on CD4+ T and CD8+ T cells . Exploring effector functionality based on mitogen stimulation demonstrated increased cytokine production by CD4+ MAIT and CD8+ MAIT cells. Decrease in absolute CD4+ T cell counts correlated positively with intracellular IFN-γ levels by CD4lo T cells, whereas increase of the same correlated negatively with TNF-α in the CD4lo T cells of HIV+HPgV+ individuals. HIV/HPgV coinfected individuals display functional CD4+ and CD8+ MAIT, TFH, and TFC cells irrespective of PD-1 expression.
    Matched MeSH terms: Antigens, Differentiation, T-Lymphocyte; Antigens, CD
  2. Kumarasamy V, Wahab AH, Chua SK, Hassan Z, Chem YK, Mohamad M, et al.
    J Virol Methods, 2007 Mar;140(1-2):75-9.
    PMID: 17140671
    A commercial dengue NS1 antigen-capture ELISA was evaluated to demonstrate its potential application for early laboratory diagnosis of acute dengue virus infection. Dengue virus NS1 antigen was detected in 199 of 213 acute serum samples from patients with laboratory confirmation of acute dengue virus infection but none of the 354 healthy blood donors' serum specimens. The dengue NS1 antigen-capture ELISA gave an overall sensitivity of 93.4% (199/213) and a specificity of 100% (354/354). The sensitivity was significantly higher in acute primary dengue (97.3%) than in acute secondary dengue (70.0%). The positive predictive value of the dengue NS1 antigen-capture ELISA was 100% and negative predictive value was 97.3%. Comparatively, virus isolation gave an overall positive isolation rate of 68.1% with a positive isolation rate of 73.9 and 31.0% for acute primary dengue and acute secondary dengue, respectively. Molecular detection of dengue RNA by RT-PCR gave an overall positive detection rate of 66.7% with a detection rate of 65.2 and 75.9% for acute primary dengue and acute secondary dengue, respectively. The results indicate that the commercial dengue NS1 antigen-capture ELISA may be superior to virus isolation and RT-PCR for the laboratory diagnosis of acute dengue infection based on a single serum sample.
    Matched MeSH terms: Antigens, Viral/blood*
  3. Jamal F, Pit S, Facklam R, Beall B
    Emerg Infect Dis, 1999 Jan-Feb;5(1):182-3.
    PMID: 10081694
    Matched MeSH terms: Antigens, Bacterial*
  4. Soe HJ, Khan AM, Manikam R, Samudi Raju C, Vanhoutte P, Sekaran SD
    J Gen Virol, 2017 Dec;98(12):2993-3007.
    PMID: 29182510 DOI: 10.1099/jgv.0.000981
    Plasma leakage is the main pathophysiological feature in severe dengue, resulting from altered vascular barrier function associated with an inappropriate immune response triggered upon infection. The present study investigated functional changes using an electric cell-substrate impedance sensing system in four (brain, dermal, pulmonary and retinal) human microvascular endothelial cell (MEC) lines infected with purified dengue virus, followed by assessment of cytokine profiles and the expression of inter-endothelial junctional proteins. Modelling of changes in electrical impedance suggests that vascular leakage in dengue-infected MECs is mostly due to the modulation of cell-to-cell interactions, while this loss of vascular barrier function observed in the infected MECs varied between cell lines and DENV serotypes. High levels of inflammatory cytokines (IL-6 and TNF-α), chemokines (CXCL1, CXCL5, CXCL11, CX3CL1, CCL2 and CCL20) and adhesion molecules (VCAM-1) were differentially produced in the four infected MECs. Further, the tight junctional protein, ZO-1, was down-regulated in both the DENV-1-infected brain and pulmonary MECs, while claudin-1, PECAM-1 and VE-cadherin were differentially expressed in these two MECs after infection. Non-purified virus stock was also studied to investigate the impact of virus stock purity on dengue-specific immune responses, and the results suggest that virus stock propagated through cell culture may include factors that mask or alter the DENV-specific immune responses of the MECs. The findings of the present study show that high DENV load differentially modulates human microvascular endothelial barrier function and disrupts the function of inter-endothelial junctional proteins during early infection with organ-specific cytokine production.
    Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/immunology; Antigens, CD31/genetics; Antigens, CD31/immunology
  5. Engelhardt KR, Gertz ME, Keles S, Schäffer AA, Sigmund EC, Glocker C, et al.
    J Allergy Clin Immunol, 2015 Aug;136(2):402-12.
    PMID: 25724123 DOI: 10.1016/j.jaci.2014.12.1945
    BACKGROUND: Mutations in dedicator of cytokinesis 8 (DOCK8) cause a combined immunodeficiency (CID) also classified as autosomal recessive (AR) hyper-IgE syndrome (HIES). Recognizing patients with CID/HIES is of clinical importance because of the difference in prognosis and management.

    OBJECTIVES: We sought to define the clinical features that distinguish DOCK8 deficiency from other forms of HIES and CIDs, study the mutational spectrum of DOCK8 deficiency, and report on the frequency of specific clinical findings.

    METHODS: Eighty-two patients from 60 families with CID and the phenotype of AR-HIES with (64 patients) and without (18 patients) DOCK8 mutations were studied. Support vector machines were used to compare clinical data from 35 patients with DOCK8 deficiency with those from 10 patients with AR-HIES without a DOCK8 mutation and 64 patients with signal transducer and activator of transcription 3 (STAT3) mutations.

    RESULTS: DOCK8-deficient patients had median IgE levels of 5201 IU, high eosinophil levels of usually at least 800/μL (92% of patients), and low IgM levels (62%). About 20% of patients were lymphopenic, mainly because of low CD4(+) and CD8(+) T-cell counts. Fewer than half of the patients tested produced normal specific antibody responses to recall antigens. Bacterial (84%), viral (78%), and fungal (70%) infections were frequently observed. Skin abscesses (60%) and allergies (73%) were common clinical problems. In contrast to STAT3 deficiency, there were few pneumatoceles, bone fractures, and teething problems. Mortality was high (34%). A combination of 5 clinical features was helpful in distinguishing patients with DOCK8 mutations from those with STAT3 mutations.

    CONCLUSIONS: DOCK8 deficiency is likely in patients with severe viral infections, allergies, and/or low IgM levels who have a diagnosis of HIES plus hypereosinophilia and upper respiratory tract infections in the absence of parenchymal lung abnormalities, retained primary teeth, and minimal trauma fractures.

    Matched MeSH terms: Antigens, Bacterial/blood; Antigens, Bacterial/immunology; Antigens, Viral/blood; Antigens, Viral/immunology
  6. Peh SC, Sandvej K, Pallesen G
    Int J Cancer, 1995 May 4;61(3):327-32.
    PMID: 7729943
    Epstein-Barr virus (EBV) type B, a less potent transformer of B lymphocytes than type A, has rarely been detected in EBV-associated neoplasms except in AIDS-related lymphomas, in which about 50% of the cases contained this sub-type. In this study we analyzed the association of EBV and the distribution of virus sub-types in Asian non-Hodgkin's lymphoma (NHL) of the upper aerodigestive tract. We studied archival material of 29 NHL cases from Malaysia. B- and T-cell associated antigens were demonstrated by immunohistochemistry, and EBV early RNA EBER-1 was demonstrated using the RNA in situ hybridization technique. EBV was detected in the majority of tumour cells in 11/13 T-NHL but in only 1/16 B-NHL. EBV was sub-typed by single-step polymerase chain reaction of the EBNA-2 gene. This was successful in 9/10 cases of EBER-1-positive tumours and all contained type-A virus only. Our results showed a preponderance of T-cell lymphoma of the upper aerodigestive tract in the ethnic Chinese group of Malaysian patients, and EBV was strongly associated with T-NHL but not with B-NHL. Our results suggest that type-A EBV is the prevalent sub-type in Asian NHL of the upper aerodigestive tract, similarly to findings in Asian nasopharyngeal carcinoma.
    Matched MeSH terms: Antigens, Viral/genetics; Antigens, CD/analysis; Epstein-Barr Virus Nuclear Antigens
  7. Amerizadeh A, Khoo BY, Teh AY, Golkar M, Abdul Karim IZ, Osman S, et al.
    BMC Infect Dis, 2013;13:287.
    PMID: 23800344 DOI: 10.1186/1471-2334-13-287
    Toxoplasma gondii is an obligate intracellular zoonotic parasite of the phylum Apicomplexa which infects a wide range of warm-blooded animals, including humans. In this study in-vivo induced antigens of this parasite was investigated using in-vivo induced antigen technology (IVIAT) and pooled sera from patients with serological evidence of acute infection.
    Matched MeSH terms: Antigens, Protozoan/genetics; Antigens, Protozoan/immunology*
  8. Candotti D, Lin CK, Belkhiri D, Sakuldamrongpanich T, Biswas S, Lin S, et al.
    Gut, 2012 Dec;61(12):1744-53.
    PMID: 22267593 DOI: 10.1136/gutjnl-2011-301281
    To investigate the molecular basis of occult hepatitis B virus (HBV) infection (OBI) in Asian blood donors.
    Matched MeSH terms: Hepatitis B Surface Antigens/genetics; Hepatitis B Surface Antigens/metabolism
  9. Ishak MF, Chua KH, Asma A, Saim L, Aminuddin BS, Ruszymah BH, et al.
    Int J Pediatr Otorhinolaryngol, 2011 Jun;75(6):835-40.
    PMID: 21543123 DOI: 10.1016/j.ijporl.2011.03.021
    This study was aimed to see the difference between chondrocytes from normal cartilage compared to chondrocytes from microtic cartilage. Specific attentions were to characterize the growth of chondrocytes in terms of cell morphology, growth profile and RT-PCR analysis.
    Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/metabolism
  10. Lau YL, Thiruvengadam G, Lee WW, Fong MY
    Parasitol Res, 2011 Sep;109(3):871-8.
    PMID: 21455621 DOI: 10.1007/s00436-011-2315-6
    In this study, we successfully expressed a chimerical surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii in Pichia pastoris. Eighty human serum samples, including 60 from confirmed cases of toxoplasmosis, were tested against the purified recombinant SAG1/2 in Western blots. Results of Western blots targeted at Toxoplasma IgG and IgM showed that the recombinant SAG1/2 reacted with all sera from the toxoplasmosis cases but none with the Toxoplasma-negative serum samples. These results showed that the P. pastoris-derived recombinant SAG1/2 was sensitive and specific and suitable for use as antigen for detecting anti-Toxoplasma antibodies. To further investigate the immunological characteristic of the recombinant protein, the recombinant SAG1/2 was injected subcutaneously into BALB/c mice, and their serum was tested against total protein lysate of T. gondii. Mice immunized with the recombinant SAG1/2 reacted specifically with the native SAG1 and SAG2 of T. gondii. Significant proliferation of splenocytes stimulated with tachyzoite total protein lysate was observed in vaccinated BALB/c mice but not in those from negative control mice. Specific production of IFN-γ, the Th1-type cytokines, was also found in stimulated splenocytes from vaccinated mice. These results show that the chimeric protein recombinant SAG1/2 can elicit a Th1-associated protection against T. gondii infections in mice. Finally, vaccinated mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P 
    Matched MeSH terms: Antigens, Protozoan/genetics; Antigens, Protozoan/immunology*
  11. Govindasamy V, Abdullah AN, Ronald VS, Musa S, Ab Aziz ZA, Zain RB, et al.
    J Endod, 2010 Sep;36(9):1504-15.
    PMID: 20728718 DOI: 10.1016/j.joen.2010.05.006
    Lately, several new stem cell sources and their effective isolation have been reported that claim to have potential for therapeutic applications. However, it is not yet clear which type of stem cell sources are most potent and best for targeted therapy. Lack of understanding of nature of these cells and their lineage-specific propensity might hinder their full potential. Therefore, understanding the gene expression profile that indicates their lineage-specific proclivity is fundamental to the development of successful cell-based therapies.
    Matched MeSH terms: Antigens, Surface/classification; Antigens, Surface/physiology
  12. Maha A, Gan GG, Koh CL
    Hematology, 2010 Dec;15(6):382-90.
    PMID: 21114900 DOI: 10.1179/102453310X12719010991902
    T cells undergo a series of complex phenotypic changes before achieving maturation. Discrete stages of T-cell differentiation are simplified to four stages (pro-, pre-, cortical and mature-T cell) and used in the classification of T-cell leukaemia. HLA-DR has been reported to be expressed in immature T-cell acute lymphoblastic leukemia (ALL) and also confer a poorer treatment outcome. Simultaneously, the genotype goes through distinct pattern changes due to rearrangement of T-cell receptor (TCR) genes. TCR gene rearrangement is important in the diagnosis of clonality and used as markers to detect minimal residual disease in lymphoproliferative disorders. We identified a subset within Pro-T and Pre-T cell cases distinguished by the expression of HLA-DR. These subgroups appeared to be more immature as rearrangement of the TCR-gamma gene was either at germline or involved only the first constant region (C1) unlike a more rearranged pattern in the HLA-DR-subgroups. We also observed a higher incidence of mediastinal mass (67%) in the HLA-DR-subgroup in the Pre-T stage. These characteristics may be useful as markers to further refine staging of T-cell ALL and determine prognosis.
    Matched MeSH terms: HLA-DR Antigens; Antigens, CD/analysis
  13. Oveissi S, Omar AR, Yusoff K, Jahanshiri F, Hassan SS
    Comp Immunol Microbiol Infect Dis, 2010 Dec;33(6):491-503.
    PMID: 19781778 DOI: 10.1016/j.cimid.2009.08.004
    The H5 gene of avian influenza virus (AIV) strain A/chicken/Malaysia/5744/2004(H5N1) was cloned into pcDNA3.1 vector, and Esat-6 gene of Mycobacterium tuberculosis was fused into downstream of the H5 gene as a genetic adjuvant for DNA vaccine candidates. The antibody level against AIV was measured using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test. Sera obtained from specific-pathogen-free chickens immunized with pcDNA3.1/H5 and pcDNA3.1/H5/Esat-6 demonstrated antibody responses as early as 2 weeks after the first immunization. Furthermore, the overall HI antibody titer in chickens immunized with pcDNA3.1/H5/Esat-6 was higher compared to the chickens immunized with pcDNA3.1/H5 (p<0.05). The results suggested that Esat-6 gene of M. tuberculosis is a potential genetic adjuvant for the development of effective H5 DNA vaccine in chickens.
    Matched MeSH terms: Antigens, Bacterial/genetics*; Antigens, Bacterial/immunology
  14. Yap YY, Hassan S, Chan M, Choo PK, Ravichandran M
    Otolaryngol Head Neck Surg, 2007 Jun;136(6):986-91.
    PMID: 17547993
    OBJECTIVES: This study examines the presence of Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC) by using polymerase chain reaction (PCR).

    STUDY DESIGN: Eighty-six postnasal biopsy samples and 71 fine-needle aspirate samples of neck masses were obtained from patients who were clinically suspect for NPC. Genomic DNA was extracted from the samples, and EBNA1, EBNA2, and LMP genes of EBV were detected by PCR. PCR results were compared with NPC histopathology findings.

    RESULTS: The sensitivity of PCR to detect EBNA1 (97.14%), EBNA2 (88.57%), and LMP (91.43%) genes of EBV in nasopharyngeal biopsy samples were higher than those in fine-needle aspirate samples.

    CONCLUSION: Detection of EBV by PCR in tissue obtained from nasopharyngeal biopsy and fine-needle aspirate samples of neck masses is a relatively inexpensive, reliable, and accurate method of diagnosing NPC. Detection of EBV genes is on par with histopathological examination (HPE) and superior to fine-needle aspirate cytology.

    SIGNIFICANCE: PCR is an ideal tool for suggesting NPC and guiding the diagnostic workup in occult primary tumors, facilitating earlier diagnosis and reducing morbidity and mortality.

    Matched MeSH terms: Epstein-Barr Virus Nuclear Antigens/analysis; Epstein-Barr Virus Nuclear Antigens/genetics
  15. Khoo JJ, Gunn A
    Malays J Pathol, 2005 Jun;27(1):9-16.
    PMID: 16676687
    AIM: To study the clinical features, histology and immunohistochemical properties of gastrointestinal stromal tumours (GISTs); and establish any parameters that can help prognosticate the malignant potential.
    METHODS: Twenty-six patients with GISTs who were seen in Sultanah Aminah Hospital Johor, Malaysia from 1999 to 2003 were selected for study. Patient, clinical characteristics and outcome based on surgical records were analysed. Tumour variables (tumour size, cellularity, mitotic count, necrosis and haemorrhage) were compared between very low to low risk groups and intermediate to high risk groups. The immunohistochemical properties of GISTs were also studied.
    RESULTS: Patients with GISTs presented mainly with pain, palpable mass or gastrointestinal tract bleeding. The tumours were seen in stomach (50%) followed by small intestine (38.5%) and rectum (11.5%). In the period of study, six patients had metastasis, mainly in the liver or peritoneum. Immunoreactivity for CD117, CD34, vimentin, S100, neuron specific enolase, alpha-smooth-muscle-actin and desmin were observed in 100%, 76.9%, 61.5%, 46.1%, 80.8%, 11.5% and 0% of tumours respectively. The behaviour of GISTs was largely dependent on tumour size and number of mitosis. Necrosis and haemorrhage were seen in tumours with high risk potential.
    Matched MeSH terms: Antigens, CD34/immunology; Antigens, CD34/metabolism
  16. Mohd-Shaharuddin N, Mohd-Adnan A, Kua BC, Nathan S
    Fish Shellfish Immunol, 2013 Mar;34(3):762-9.
    PMID: 23296118 DOI: 10.1016/j.fsi.2012.11.052
    Cryptocaryon irritans causes Cyptocaryonosis or white spot disease in a wide range of marine fish including Lates calcarifer (Asian seabass). However, the immune response of this fish to the parasite is still poorly understood. In this study, quantitative polymerase chain reaction (qPCR) was performed to assess the expression profile of immune-related genes in L. calcarifer infected by C. irritans. A total of 21 immune-related genes encoding various functions in the fish immune system were utilized for the qPCR analysis. The experiment was initiated with the infection of juvenile fish by exposure to theronts from 200 C. irritans cysts, and non-infected juvenile fish were used as controls. Spleen, liver, gills and kidney tissues were harvested at three days post-infection from control and infected fish. In addition, organs were also harvested on day-10 post-infection from fish that had been allowed to recover from day-4 up to day-10 post-infection. L. calcarifer exhibited pathological changes on day-3 post-infection with the characteristic presence of white spots on the entire fish body, excessive mucus production and formation of a flap over the fish eye. High quality total RNA was extracted from all tissues and qPCR was performed. The qPCR analysis on the cohort of 21 immune-related genes of the various organs harvested on day-3 post-infection demonstrated that most genes were induced significantly (p 
    Matched MeSH terms: Histocompatibility Antigens Class II/genetics; Histocompatibility Antigens Class II/metabolism
  17. Sosroseno W, Bird PS, Gemmell E, Seymour GJ
    Oral Microbiol. Immunol., 2003 Oct;18(5):318-22.
    PMID: 12930525
    Mucosal presentation of Actinomyces viscosus results in antigen-specific systemic immune suppression, known as oral tolerance. The aim of the present study was to determine the mechanism by which this oral tolerance is induced. DBA/2 mice were gastrically immunized with A. viscosus. Serum, Peyer's patch (PP) and spleen cells were transferred to syngeneic recipients which were then systemically challenged with the sameiA. viscosus strain. To determine antigen-specificity of cells from gastrically immunized mice, recipients which received immune spleen cells were also challenged with Porphyromonas gingivalis. One week after the last systemic challenge, the delayed type hypersensitivity (DTH) response was determined by footpad swelling and the level of serum IgG, IgA and IgM antibodies to A. viscosus or P. gingivalis measured by an ELISA. No suppression of DTH response or of specific serum antibodies was found in recipients which received serum from gastrically immunized mice. Systemic immune suppression to A. viscosus was observed in recipients which had been transferred with PP cells obtained 2 days but not 4 and 6 days after gastric immunization with A. viscosus. Conversely, suppressed immune response could be seen in recipients transferred with spleen cells obtained 6 days after gastric immunization. The immune response to P. gingivalis remained unaltered in mice transferred with A. viscosus-gastrically immunized cells. The results of the present study suggest that oral tolerance induced by A. viscosus may be mediated by antigen-specific suppressor cells which originate in the PP and then migrate to the spleen.
    Matched MeSH terms: Antigens, Bacterial/blood; Antigens, Bacterial/immunology
  18. Ng SM, Ariffin WA, Lin HP, Chan LL, Chin YM
    J Trop Pediatr, 2000 Apr;46(2):73-8.
    PMID: 10822932
    The purpose of the study was to evaluate the incidence of myeloid antigen coexpression and its prognostic significance in childhood acute lymphoblastic leukemia (ALL) in Malaysia. A retrospective study was conducted of all ALL cases (< or = 12 years old) diagnosed and treated in University Hospital, Kuala Lumpur, Malaysia between 1 January 1992 and 30 May 1995, with available immunophenotype data. Presenting features and treatment outcome of 39 B-lineage ALL patients with myeloid antigen coexpression (My+B) were compared with 112 B-lineage ALL patients without myeloid antigen coexpression (My-B) for similarity in demographic, clinical and laboratory features and their treatment outcome. My+B and My-B patients were treated with a uniform treatment protocol. Myeloid antigen coexpression was defined as more than 30% isolated leukemic cells positive for CD13 and/or CD33. The ages at diagnoses ranged from 2 months to 12 years. Median age was 4 years. The incidence of myeloid antigen coexpression was 23 per cent. Univariate analyses showed that presenting features were similar between My+B and My-B with regard to age, sex, race, FAB morphology, white cell count, hemoglobin level, platelet count, liver/spleen size, central nervous system or mediastinal involvement, presence of lymphadenopathy, and proportion of blast cells detected in the marrow. Treatment outcome were not significant between the two groups. The 2-year event free survival was achieved in 44 per cent of My+B and 57 per cent of My-B (p = 0.11). The 2-year overall survival rates were 62 per cent for My+B vs. 77 per cent for My-B (p = 0.08). This study demonstrates that myeloid antigen coexpression is fairly common and constitutes 23 per cent of childhood ALL within the Malaysian population and that it is not an adverse risk factor in childhood ALL.
    Matched MeSH terms: Antigens, Differentiation, Myelomonocytic/analysis*; Antigens, Differentiation, Myelomonocytic/drug effects
  19. Vockerodt M, Vrzalikova K, Ibrahim M, Nagy E, Margielewska S, Hollows R, et al.
    J Pathol, 2019 06;248(2):142-154.
    PMID: 30666658 DOI: 10.1002/path.5237
    The Epstein-Barr virus (EBV) is found almost exclusively in the activated B-cell (ABC) subtype of diffuse large B-cell lymphoma (DLBCL), yet its contribution to this tumour remains poorly understood. We have focused on the EBV-encoded latent membrane protein-1 (LMP1), a constitutively activated CD40 homologue expressed in almost all EBV-positive DLBCLs and which can disrupt germinal centre (GC) formation and drive lymphomagenesis in mice. Comparison of the transcriptional changes that follow LMP1 expression with those that follow transient CD40 signalling in human GC B cells enabled us to define pathogenic targets of LMP1 aberrantly expressed in ABC-DLBCL. These included the down-regulation of S1PR2, a sphingosine-1-phosphate (S1P) receptor that is transcriptionally down-regulated in ABC-DLBCL, and when genetically ablated leads to DLBCL in mice. Consistent with this, we found that LMP1-expressing primary ABC-DLBCLs were significantly more likely to lack S1PR2 expression than were LMP1-negative tumours. Furthermore, we showed that the down-regulation of S1PR2 by LMP1 drives a signalling loop leading to constitutive activation of the phosphatidylinositol-3-kinase (PI3-K) pathway. Finally, core LMP1-PI3-K targets were enriched for lymphoma-related transcription factors and genes associated with shorter overall survival in patients with ABC-DLBCL. Our data identify a novel function for LMP1 in aggressive DLBCL. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
    Matched MeSH terms: Antigens, CD40/genetics; Antigens, CD40/metabolism
  20. Mohamud R, Azlan M, Yero D, Alvarez N, Sarmiento ME, Acosta A, et al.
    BMC Immunol, 2013;14 Suppl 1:S5.
    PMID: 23458635 DOI: 10.1186/1471-2172-14-S1-S5
    Recombinant Mycobacterium bovis bacille Calmette-Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused to B cell epitopes from ESAT-6, CFP-10 and MTP40 proteins (rBCG032) were used to immunize Balb/c mice. Total IgG responses were determined against Mtb8.4 antigen and ESAT-6 and CFP-10 B cell epitopes after immunization with rBCG032. Mice immunized with rBCG032 showed a significant increase in IgG1 and IgG2a antibodies against ESAT-6 and MTP40 (P1) B cell epitopes and IgG3 against both P1 and P2 B cell epitopes of MPT40. Splenocytes from mice immunized with rBCG018 proliferated against Ag85B P2 and P3 T cell epitopes and Mtb8.4 protein whereas those from mice-immunized with rBCG032 responded against all Ag85B epitopes and the ESAT-6 B cell epitope. CD4⁺ and CD8⁺ lymphocytes from mice immunized with rBCG018 produced primarily Th1 type cytokines in response to the T cell epitopes. Similar pattern of recognition against the T cell epitopes were obtained with rBCG032 with the additional recognition of ESAT-6, CFP-10 and one of the MTP40 B cell epitopes with the same pattern of cytokines. This study demonstrates that rBCG constructs expressing either T or T and B cell epitopes of MTB induced appropriate immunogenicity against MTB.
    Matched MeSH terms: Antigens, Bacterial/immunology*; Antigens, Bacterial/metabolism
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