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Fulltext Coeliac disease: immunogenicity studies of barley hordein and rye secalin-derived peptides

Wahab WA, Šuligoj T, Ellis J, Côrtez-Real B, Ciclitira PJ

Int J Exp Pathol, 2016 Aug;97(4):303-309.
PMID: 27659035 DOI: 10.1111/iep.12199

Coeliac disease (CD) is an inflammatory disorder of the small intestine. It includes aberrant adaptive immunity with presentation of CD toxic gluten peptides by HLA-DQ2 or DQ8 molecules to gluten-sensitive T cells. A ω-gliadin/C-hordein peptide (QPFPQPEQPFPW) and a rye-derived secalin peptide (QPFPQPQQPIPQ) were proposed to be toxic in CD, as they yielded positive responses when assessed with peripheral blood T-cell clones derived from individuals with CD. We sought to assess the immunogenicity of the candidate peptides using gluten-sensitive T-cell lines obtained from CD small intestinal biopsies. We also sought to investigate the potential cross-reactivity of wheat gluten-sensitive T-cell lines with peptic-tryptic digested barley hordein (PTH) and rye secalin (PTS). Synthesised candidate peptides were deamidated with tissue transglutaminase (tTG). Gluten-sensitive T-cell lines were generated by culturing small intestinal biopsies from CD patients with peptic-tryptic gluten (PTG), PTH or PTS, along with autologous PBMCs for antigen presentation. The stimulation indices were determined by measuring the relative cellular proliferation via incorporation of (3) H-thymidine. The majority of T-cell lines reacted to the peptides studied. There was also cross-reactivity between wheat gluten-sensitive T-cell lines and the hordein, gliadin and secalin peptides. PTH, PTS, barley hordein and rye secalin-derived CD antigen-sensitive T-cell lines showed positive stimulation with PTG. ω-gliadin/C-hordein peptide and rye-derived peptide are immunogenic to gluten-sensitive T-cell lines and potentially present in wheat, rye and barley. Additional CD toxic peptides may be shared.

Matched MeSH terms: T-Lymphocytes/cytology; T-Lymphocytes/immunology
Human mesenchymal stromal cells modulate T-cell immune response via transcriptomic regulation

Vellasamy S, Tong CK, Azhar NA, Kodiappan R, Chan SC, Veerakumarasivam A, et al.

Cytotherapy, 2016 10;18(10):1270-83.
PMID: 27543068 DOI: 10.1016/j.jcyt.2016.06.017

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) have been identified as pan-immunosuppressant in various in vitro and in vivo inflammatory models. Although the immunosuppressive activity of MSCs has been explored in various contexts, the precise molecular signaling pathways that govern inhibitory functions remain poorly elucidated.
METHODS: By using a microarray-based global gene expression profiling system, this study aimed to decipher the underlying molecular pathways that may mediate the immunosuppressive activity of umbilical cord-derived MSCs (UC-MSCs) on activated T cells.
RESULTS: In the presence of UC-MSCs, the proliferation of activated T cells was suppressed in a dose-depended manner by cell-to-cell contact mode via an active cell-cycle arrest at the G0/G1 phase of the cell cycle. The microarray analysis revealed that particularly, IFNG, CXCL9, IL2, IL2RA and CCND3 genes were down-regulated, whereas IL11, VSIG4, GFA1, TIMP3 and BBC3 genes were up-regulated by UC-MSCs. The dysregulated gene clusters associated with immune-response-related ontologies, namely, lymphocyte proliferation or activation, apoptosis and cell cycle, were further analyzed.
CONCLUSIONS: Among the nine canonical pathways identified, three pathways (namely T-helper cell differentiation, cyclins and cell cycle regulation, and gap/tight junction signalling pathways) were highly enriched with these dysregulated genes. The pathways represent putative molecular pathways through which UC-MSCs elicit immunosuppressive activity toward activated T cells. This study provides a global snapshot of gene networks and pathways that contribute to the ability of UC-MSCs to suppress activated T cells.

Matched MeSH terms: T-Lymphocytes/immunology*; T-Lymphocytes/metabolism*
Fulltext Tropomyosin Receptor Kinase C Targeted Delivery of a Peptidomimetic Ligand-Photosensitizer Conjugate Induces Antitumor Immune Responses Following Photodynamic Therapy

Kue CS, Kamkaew A, Voon SH, Kiew LV, Chung LY, Burgess K, et al.

Sci Rep, 2016 11 17;6:37209.
PMID: 27853305 DOI: 10.1038/srep37209

Tropomyosin receptor kinase C (TrkC) targeted ligand-photosensitizer construct, IYIY-diiodo-boron-dipyrromethene (IYIY-I2-BODIPY) and its scrambled counterpart YIYI-I2-BODIPY have been prepared. IYIY-I2-BODIPY binds TrkC similar to neurotrophin-3 (NT-3), and NT-3 has been reported to modulate immune responses. Moreover, it could be shown that photodynamic therapy (PDT) elevates antitumor immune responses. This prompted us to investigate the immunological impacts mediated by IYIY-I2-BODIPY in pre- and post-PDT conditions. We demonstrated that IYIY-I2-BODIPY (strong response) and YIYI-I2-BODIPY (weak response) at 10 mg/kg, but not I2-BODIPY control, increased the levels of IL-2, IL-4, IL-6 and IL-17, but decreased the levels of systemic immunoregulatory mediators TGF-β, myeloid-derived suppressor cells and regulatory T-cells. Only IYIY-I2-BODIPY enhanced the IFN-γ+ and IL-17+ T-lymphocytes, and delayed tumor growth (~20% smaller size) in mice when administrated daily for 5 days. All those effects were observed without irradiation; when irradiated (520 nm, 100 J/cm2, 160 mW/cm2) to produce PDT effects (drug-light interval 1 h), IYIY-I2-BODIPY induced stronger responses. Moreover, photoirradiated IYIY-I2-BODIPY treated mice had high levels of effector T-cells compared to controls. Adoptive transfer of immune cells from IYIY-I2-BODIPY-treated survivor mice that were photoirradiated gave significantly delayed tumor growth (~40-50% smaller size) in recipient mice. IYIY-I2-BODIPY alone and in combination with PDT modulates the immune response in such a way that tumor growth is suppressed. Unlike immunosuppressive conventional chemotherapy, IYIY-I2-BODIPY can act as an immune-stimulatory chemotherapeutic agent with potential applications in clinical cancer treatment.

Matched MeSH terms: T-Lymphocytes, Regulatory/immunology*; T-Lymphocytes, Regulatory/pathology
Fulltext Reduced CD4+ terminally differentiated effector memory T cells in moderate-severe house dust mites sensitized allergic rhinitis patients

Sani MM, Ashari NSM, Abdullah B, Wong KK, Musa KI, Mohamud R, et al.

Asian Pac J Allergy Immunol, 2019 Sep;37(3):138-146.
PMID: 29981564 DOI: 10.12932/AP-191217-0220

BACKGROUND: Terminally differentiated effector memory (TEMRA) T cells exert potent effector function after activation. The proportions of CD4+ T cell subsets especially memory cells in allergic rhinitis (AR) patients sensitized to house dust mites (HDMs) have not been extensively studied.
OBJECTIVE: This study aimed to compare the mean percentages and absolute counts of CD4+ memory T cell subsets between: (i) non-allergic controls and AR patients; (ii) mild AR patients and moderate-severe AR patients.
METHODS: Sensitization to Dermatophagoides farinae and Dermatophagoides pteronyssinus were determined in 33 non -allergic controls, 28 mild AR and 29 moderate-severe AR patients. Flow cytometry was used to determine the percentage of CD4+ na?ve (TN; CD45RA+CCR7+), central memory (TCM; CD45RA-CCR7+), effector memory (TEM; CD45RA-CCR7-) and TEMRA (CD45RA+CCR7-) T cells from the peripheral blood. The absolute counts of CD4+ T cell subsets were obtained by dual platform method from flow cytometer and hematology analyzer.
RESULTS: There were no significant differences in the mean percentages and absolute counts of CD4+ T cell subsets between non-allergic controls and AR patients sensitized to HDMs. However, there were significant reduction in the mean percentage (p=0.0307) and absolute count (p=0.0309) of CD4+ TEMRA cells in moderate-severe AR patients compared to mild AR patients sensitized to HDMs and 13/24 (54.2%) moderate-severe AR patients sensitized to HDMs had persistent symptoms.
CONCLUSION: Reduction in the mean percentage and absolute count of CD4+CD45RA+CCR7- TEMRA cells were observed in moderate-severe AR patients compared to mild AR patients in our population of AR patients sensitized to HDMs.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology*; CD4-Positive T-Lymphocytes/metabolism
Synchrotron microbeam radiotherapy evokes a different early tumor immunomodulatory response to conventional radiotherapy in EMT6.5 mammary tumors

Yang Y, Swierczak A, Ibahim M, Paiva P, Cann L, Stevenson AW, et al.

Radiother Oncol, 2019 04;133:93-99.
PMID: 30935588 DOI: 10.1016/j.radonc.2019.01.006

BACKGROUND: Synchrotron microbeam radiation therapy (MRT) is a new, evolving form of radiotherapy that has potential for clinical application. Several studies have shown in preclinical models that synchrotron MRT achieves equivalent tumor control to conventional radiotherapy (CRT) but with significantly reduced normal tissue damage.
METHODS: To explore differences between these two modalities, we assessed the immune cell infiltrate into EMT6.5 mammary tumors after CRT and MRT.
RESULTS: CRT induced marked increases in tumor-associated macrophages and neutrophils while there were no increases in these populations following MRT. In contrast, there were higher numbers of T cells in the MRT treated tumors. There were also increased levels of CCL2 by immunohistochemistry in tumors subjected to CRT, but not to MRT. Conversely, we found that MRT induced higher levels of pro-inflammatory genes in tumors than CRT.
CONCLUSION: Our data are the first to demonstrate substantial differences in macrophage, neutrophil and T cell numbers in tumors following MRT versus CRT, providing support for the concept that MRT evokes a different immunomodulatory response in tumors compared to CRT.

Matched MeSH terms: T-Lymphocytes/immunology; T-Lymphocytes/radiation effects
Fulltext Rhaphidophora korthalsii modulates peripheral blood natural killer cell proliferation, cytokine secretion and cytotoxicity

Yeap SK, Omar AR, Ho WY, Beh BK, Ali AM, Alitheen NB

BMC Complement Altern Med, 2013;13:145.
PMID: 23800124 DOI: 10.1186/1472-6882-13-145

Rhaphidophora korthalsii (Araceae) is a root-climber plant which has been widely used in Chinese traditional medicine for cancer and skin disease treatment. Previous reports have recorded its immunomodulatory effects on mice splenocyte and human peripheral blood. This study investigated the potential immunostimulatory effect of Rhaphidophora korthalsii on human PBMC enriched NK cell.

Matched MeSH terms: T-Lymphocytes/cytology; T-Lymphocytes/drug effects; T-Lymphocytes/immunology
Immunomodulation by melatonin: its significance for seasonally occurring diseases

Srinivasan V, Spence DW, Trakht I, Pandi-Perumal SR, Cardinali DP, Maestroni GJ

Neuroimmunomodulation, 2008;15(2):93-101.
PMID: 18679047 DOI: 10.1159/000148191

Melatonin is not only synthesized by the pineal gland but also in many other organs and tissues of the body, particularly by lymphoid organs such as the bone marrow, thymus and lymphocytes. Melatonin participates in various functions of the body, among which its immunomodulatory role has assumed considerable significance in recent years. Melatonin has been shown to be involved in the regulation of both cellular and humoral immunity. Melatonin not only stimulates the production of natural killer cells, monocytes and leukocytes, but also alters the balance of T helper (Th)-1 and Th-2 cells mainly towards Th-1 responses and increases the production of relevant cytokines such as interleukin (IL)-2, IL-6, IL-12 and interferon-gamma. The regulatory function of melatonin on immune mechanisms is seasonally dependent. This fact may in part account for the cyclic pattern of symptom expression shown by certain infectious diseases, which become more pronounced at particular times of the year. Moreover, melatonin-induced seasonal changes in immune function have also been implicated in the pathogenesis of seasonal affective disorder and rheumatoid arthritis. The clinical significance of the seasonally changing immunomodulatory role of melatonin is discussed in this review.

Matched MeSH terms: T-Lymphocytes/immunology; T-Lymphocytes/metabolism; T-Lymphocytes/secretion
Role of CD4 and CD8 T-cells in the induction of oral tolerance to Actinomyces viscosus in mice

Sosroseno W, Bird PS, Gemmell E, Seymour GJ

Oral Microbiol. Immunol., 2006 Jun;21(3):151-8.
PMID: 16626371

Mucosal presentation of Actinomyces viscosus results in the induction of antigen specific systemic suppressor cells in mice. The aim of the present study was to determine the phenotype of the suppressor cells responsible for the induction of oral tolerance to low doses of A. viscosus. When CD8 cell-depleted DBA/2 mice were intragastrically immunized and systemically immunized with A. viscosus, the delayed type hypersensitivity response was suppressed but not the levels of antigen specific serum antibodies. Adoptive transfer of orally tolerized CD4(+) cells to CD4(+)-depleted mice resulted in suppression of delayed type hypersensitivity response but not of the levels of antigen specific serum antibodies. In contrast, adoptive transfer of orally immunized CD8(+) cells to CD8(+)-depleted mice resulted in partially suppressed delayed type hypersensitivity response but significantly inhibited the levels of antigen specific serum antibodies. When orally tolerized CD8(+) cells were cocultured with systemically immunized CD8(+) cell-depleted spleen cells, splenic specific antibodies were inhibited. However, no suppression of splenic specific antibodies could be observed in the cultures containing orally tolerized CD4(+) cells and systemically immunized CD4(+) cell-depleted spleen cells. The results of the present study suggest that oral tolerance of humoral and cellular immunity induced by low doses of A. viscosus may be mediated by CD8(+) and CD4(+) cells, respectively.

Matched MeSH terms: CD4-Positive T-Lymphocytes/physiology*; CD8-Positive T-Lymphocytes/physiology*
Fulltext Evidence and impact of human papillomavirus latency

Gravitt PE

Open Virol J, 2012;6:198-203.
PMID: 23341855 DOI: 10.2174/1874357901206010198

At present, there is no consensus in the scientific community regarding the ability for human papillomavirus (HPV) infections to establish latency. Based on animal studies, a model of papillomavirus latency has been proposed in which papillomaviruses can be retained in the basal epithelial stem cell pool as latent infections and periodically induced to reactivate when the stem cell divides and one daughter cell is committed to terminal differentiation and induction of the viral life cycle. Tissue resident memory T-cells are hypothesized to control these periodic reactivation episodes and thus limit their duration. In this paper, evidence from human studies consistent with this model of papillomavirus latency is reviewed. Given the strong circumstantial evidence supporting a natural history of HPV infection which includes a immunologically controlled latent state, the longer term implications of HPV latency on a highly infected and aging population may warrant a more serious evaluation.

Matched MeSH terms: T-Lymphocytes
Fulltext A case study of human immunodeficiency virus with positive seroconversion to negative

Paranthaman V, Yip HL, Ker HB

Malays Fam Physician, 2015;10(1):44-6.
PMID: 26425294 MyJurnal

This case study demonstrates a 36-year-old ex-intravenous drug user (IVDU) who had been initially tested positive for human immunodeficiency virus (HIV) twice using Enzyme Immunoassay (EIA) method (Particle agglutination, PA done), but a year later he was tested HIV-negative. The patient was asymptomatic for HIV and T helper cells (CD4) count remained stable throughout this period. In light of this case, there may be a need to retest by molecular methods for high risk category patients who were initially diagnosed HIV-positive, but later showing an unexpected clinical course, such as a rising or stable CD4 titre over the years.

Matched MeSH terms: T-Lymphocytes, Helper-Inducer
The Antimetastatic and Antiangiogenesis Effects of Kefir Water on Murine Breast Cancer Cells

Zamberi NR, Abu N, Mohamed NE, Nordin N, Keong YS, Beh BK, et al.

Integr Cancer Ther, 2016 Dec;15(4):NP53-NP66.
PMID: 27230756

BACKGROUND: Kefir is a unique cultured product that contains beneficial probiotics. Kefir culture from other parts of the world exhibits numerous beneficial qualities such as anti-inflammatory, immunomodulation, and anticancer effects. Nevertheless, kefir cultures from different parts of the world exert different effects because of variation in culture conditions and media. Breast cancer is the leading cancer in women, and metastasis is the major cause of death associated with breast cancer. The antimetastatic and antiangiogenic effects of kefir water made from kefir grains cultured in Malaysia were studied in 4T1 breast cancer cells.
METHODS: 4T1 cancer cells were treated with kefir water in vitro to assess its antimigration and anti-invasion effects. BALB/c mice were injected with 4T1 cancer cells and treated orally with kefir water for 28 days.
RESULTS: Kefir water was cytotoxic toward 4T1 cells at IC50 (half-maximal inhibitory concentration) of 12.5 and 8.33 mg/mL for 48 and 72 hours, respectively. A significant reduction in tumor size and weight (0.9132 ± 0.219 g) and a substantial increase in helper T cells (5-fold) and cytotoxic T cells (7-fold) were observed in the kefir water-treated group. Proinflammatory and proangiogenic markers were significantly reduced in the kefir water-treated group.
CONCLUSIONS: Kefir water inhibited tumor proliferation in vitro and in vivo mainly through cancer cell apoptosis, immunomodulation by stimulating T helper cells and cytotoxic T cells, and anti-inflammatory, antimetastatic, and antiangiogenesis effects. This study brought out the potential of the probiotic beverage kefir water in cancer treatment.

Matched MeSH terms: T-Lymphocytes, Helper-Inducer/drug effects; T-Lymphocytes, Cytotoxic/drug effects
Fulltext Advances in immunotherapy using dendritic cells

Radhakrishnan, Ammu Kutty

International e-Journal of Science, Medicine & Education, 2012;6(10):0-0.
MyJurnal

The immune system is the host natural defence against cancer. Cancers are caused by progressive growth of the progeny of a single transformed host cell. The immune system is generally not able to mount immune responses to “self-antigens”, due to various mechanisms of immunological tolerance that are in place. This means that despite possessing a natural defence against tumours, many of the cancer patients may not be able
to mount an effective immune response to fight the tumours. Dendritic cells (DC) are highly specialised in antigen presenting that can initiate and stimulate immune responses. These cells have the ability to stimulate naïve T cell proliferation and perform specific stimulatory and tolerogenic functions respectively. When the DC are activated by antigens, these cells
undergoes further maturation and migrate to secondary lymphoid tissues, present antigen to T cells and finally induce an immune response. The ability of the DC to activate naïve and primed T-lymphocytes makes these cells a good candidate to be explored as a potential immunotherapeutic agent that can modulate antitumour immune responses in the affected host.

Matched MeSH terms: T-Lymphocytes
Fulltext Dengue: breakbone fever, hemorrhagia or shock

Shamala, D.

JUMMEC, 2008;11(2):39-52.
MyJurnal

Dengue virus infection has been endemic in Malaysia and in the region for decades and the disease caused by the virus has led to increased morbidity and mortality each year. Dengue is now endemic in more than 110 countries worldwide with two-fifths of the world's population at risk. Dengue fever is a flu-like illness and clinical features vary with the age of the patient. Dengue haemorrhagic fever on the other hand, is characterized by high fever, haemorrhagic phenomena and in severe cases, circulatory failure. There is no specific treatment for dengue fever but careful clinical management frequently saves the lives of these patients. Vaccine development has been difficult as protection against one or two dengue viruses could actually increase the risk of more serious diseases. At present, the only method of preventing dengue is to combat the vector mosquitoes. Dengue is diagnosed by viral isolation and or serology. Current methods, some in-house and others commercial, are far from satisfactory. My laboratory has developed, evaluated and validated tests for dengue that now enable detection on the first day of illness in most cases. At the same time an important aspect of dengue prevention is protection. To this end, we have been investigating the various immune parameters such as T-cells, cytokines and antibody neutralizing activities to show that specific immune responses do occur in a selected Malaysian population which are HLA restricted, cytokine mediated and directed specifically at certain regions of the virus.

Matched MeSH terms: T-Lymphocytes
Fulltext Peripheral immune response in the African green monkey model following Nipah-Malaysia virus exposure by intermediate-size particle aerosol

Lara A, Cong Y, Jahrling PB, Mednikov M, Postnikova E, Yu S, et al.

PLoS Negl Trop Dis, 2019 06;13(6):e0007454.
PMID: 31166946 DOI: 10.1371/journal.pntd.0007454

The ability to appropriately mimic human disease is critical for using animal models as a tool for understanding virus pathogenesis. In the case of Nipah virus (NiV), infection of humans appears to occur either through inhalation, contact with or consumption of infected material. In two of these circumstances, respiratory or sinusoidal exposure represents a likely route of infection. In this study, intermediate-size aerosol particles (~7 μm) of NiV-Malaysia were used to mimic potential routes of exposure by focusing viral deposition in the upper respiratory tract. Our previous report showed this route of exposure extended the disease course and a single animal survived the infection. Here, analysis of the peripheral immune response found minimal evidence of systemic inflammation and depletion of B cells during acute disease. However, the animal that survived infection developed an early IgM response with rapid development of neutralizing antibodies that likely afforded protection. The increase in NiV-specific antibodies correlated with an expansion of the B cell population in the survivor. Cell-mediated immunity was not clearly apparent in animals that succumbed during the acute phase of disease. However, CD4+ and CD8+ effector memory cells increased in the survivor with correlating increases in cytokines and chemokines associated with cell-mediated immunity. Interestingly, kinetic changes of the CD4+ and CD8bright T cell populations over the course of acute disease were opposite from animals that succumbed to infection. In addition, increases in NK cells and basophils during convalescence of the surviving animal were also evident, with viral antigen found in NK cells. These data suggest that a systemic inflammatory response and "cytokine storm" are not major contributors to NiV-Malaysia pathogenesis in the AGM model using this exposure route. Further, these data demonstrate that regulation of cell-mediated immunity, in addition to rapid production of NiV specific antibodies, may be critical for surviving NiV infection.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology; CD8-Positive T-Lymphocytes/immunology
Fulltext Immune Biomarkers for Diagnosis and Treatment Monitoring of Tuberculosis: Current Developments and Future Prospects

Yong YK, Tan HY, Saeidi A, Wong WF, Vignesh R, Velu V, et al.

Front Microbiol, 2019;10:2789.
PMID: 31921004 DOI: 10.3389/fmicb.2019.02789

Tuberculosis (TB) treatment monitoring is paramount to clinical decision-making and the host biomarkers appears to play a significant role. The currently available diagnostic technology for TB detection is inadequate. Although GeneXpert detects total DNA present in the sample regardless live or dead bacilli present in clinical samples, all the commercial tests available thus far have low sensitivity. Humoral responses against Mycobacterium tuberculosis (Mtb) antigens are generally low, which precludes the use of serological tests for TB diagnosis, prognosis, and treatment monitoring. Mtb-specific CD4+ T cells correlate with Mtb antigen/bacilli burden and hence might serve as good biomarkers for monitoring treatment progress. Omics-based techniques are capable of providing a more holistic picture for disease mechanisms and are more accurate in predicting TB disease outcomes. The current review aims to discuss some of the recent advances on TB biomarkers, particularly host biomarkers that have the potential to diagnose and differentiate active TB and LTBI as well as their use in disease prognosis and treatment monitoring.

Matched MeSH terms: CD4-Positive T-Lymphocytes
Fulltext Hyperthermia by near infrared radiation induced immune cells activation and infiltration in breast tumor

Wan Mohd Zawawi WFA, Hibma MH, Salim MI, Jemon K

Sci Rep, 2021 05 13;11(1):10278.
PMID: 33986437 DOI: 10.1038/s41598-021-89740-0

Breast cancer is the most common cancer that causes death in women. Conventional therapies, including surgery and chemotherapy, have different therapeutic effects and are commonly associated with risks and side effects. Near infrared radiation is a technique with few side effects that is used for local hyperthermia, typically as an adjuvant to other cancer therapies. The understanding of the use of near NIR as a monotherapy, and its effects on the immune cells activation and infiltration, are limited. In this study, we investigate the effects of HT treatment using NIR on tumor regression and on the immune cells and molecules in breast tumors. Results from this study demonstrated that local HT by NIR at 43 °C reduced tumor progression and significantly increased the median survival of tumor-bearing mice. Immunohistochemical analysis revealed a significant reduction in cells proliferation in treated tumor, which was accompanied by an abundance of heat shock protein 70 (Hsp70). Increased numbers of activated dendritic cells were observed in the draining lymph nodes of the mice, along with infiltration of T cells, NK cells and B cells into the tumor. In contrast, tumor-infiltrated regulatory T cells were largely diminished from the tumor. In addition, higher IFN-γ and IL-2 secretion was observed in tumor of treated mice. Overall, results from this present study extends the understanding of using local HT by NIR to stimulate a favourable immune response against breast cancer.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology; CD8-Positive T-Lymphocytes/immunology
The expression of cytokine genes in the peritoneal macrophages and splenic CD4- and CD8-positive lymphocytes of the nonobese diabetic mice

Yaacob NS, Kaderi MA, Norazmi MN

J Clin Immunol, 2004 Mar;24(2):177-84.
PMID: 15024185 DOI: 10.1023/B:JOCI.0000019783.61674.1d

Type 1 diabetes is an autoimmune disease that results from the destruction of the insulin-producing pancreatic beta islet cells, probably via the influence of cytokines. However, direct correlation between the expression of selected cytokines by various immune cells at different time points during the progression of the disease has not yet been clearly demonstrated. In this study, we showed that the mRNA expression of the pro-inflammatory cytokines, TNF-alpha, IL-1 beta, IL-6, and GM-CSF, were increased while the anti-inflammatory cytokine, TGF-beta, decreased in the peritoneal macrophages of nonobese diabetic (NOD) mice. IL-6 expression however decreased when the mice became diabetic. Surprisingly the expression of IFN-gamma and IL-2 by splenic CD4+ cells were lower in 5-week-old NOD mice as compared to the nonobese diabetic resistant (NOR) control mice, but their expression was higher in older NOD mice. The expression of IL-4 and IL-10 decreased in splenic CD4-positive lymphocytes. Splenic CD8-positive lymphocytes expressed increased levels of IFN-gamma and IL-10 but the latter decreased sharply when diabetes occurred. The relevance of these findings to the pathogenesis of type 1 diabetes is discussed.

Matched MeSH terms: CD4-Positive T-Lymphocytes/immunology*; CD8-Positive T-Lymphocytes/immunology*
Fulltext A tryptophan metabolite made by a gut microbiome eukaryote induces pro-inflammatory T cells

Wojciech L, Png CW, Koh EY, Kioh DYQ, Deng L, Wang Z, et al.

EMBO J, 2023 Nov 02;42(21):e112963.
PMID: 37743772 DOI: 10.15252/embj.2022112963

The large intestine harbors microorganisms playing unique roles in host physiology. The beneficial or detrimental outcome of host-microbiome coexistence depends largely on the balance between regulators and responder intestinal CD4+ T cells. We found that ulcerative colitis-like changes in the large intestine after infection with the protist Blastocystis ST7 in a mouse model are associated with reduction of anti-inflammatory Treg cells and simultaneous expansion of pro-inflammatory Th17 responders. These alterations in CD4+ T cells depended on the tryptophan metabolite indole-3-acetaldehyde (I3AA) produced by this single-cell eukaryote. I3AA reduced the Treg subset in vivo and iTreg development in vitro by modifying their sensing of TGFβ, concomitantly affecting recognition of self-flora antigens by conventional CD4+ T cells. Parasite-derived I3AA also induces over-exuberant TCR signaling, manifested by increased CD69 expression and downregulation of co-inhibitor PD-1. We have thus identified a new mechanism dictating CD4+ fate decisions. The findings thus shine a new light on the ability of the protist microbiome and tryptophan metabolites, derived from them or other sources, to modulate the adaptive immune compartment, particularly in the context of gut inflammatory disorders.

Matched MeSH terms: T-Lymphocytes, Regulatory
Regulation of CD8+ T-cell cytotoxicity in HIV-1 infection

Saeidi A, Buggert M, Che KF, Kong YY, Velu V, Larsson M, et al.

Cell Immunol, 2015 Nov-Dec;298(1-2):126-33.
PMID: 26520669 DOI: 10.1016/j.cellimm.2015.10.009

Understanding the mechanisms involved in cellular immune responses against control of human immunodeficiency virus (HIV) infection is key to development of effective immunotherapeutic strategies against viral proliferation. Clear insights into the regulation of cytotoxic CD8+ T cells is crucial to development of effective immunotherapeutic strategies due to their unique ability to eliminate virus-infected cells during the course of infection. Here, we reviewed the roles of transcription factors, co-inhibitory molecules and regulatory cytokines following HIV infection and their potential significance in regulating the cytotoxic potentials of CD8+ T cells.

Matched MeSH terms: T-Lymphocytes, Cytotoxic/immunology*
Fulltext Biomarkers of severe dengue disease - a review

John DV, Lin YS, Perng GC

J Biomed Sci, 2015;22:83.
PMID: 26462910 DOI: 10.1186/s12929-015-0191-6

Dengue virus infection presents a wide spectrum of manifestations including asymptomatic condition, dengue fever (DF), or severe forms, such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) in affected individuals. The early prediction of severe dengue in patients without any warning signs who may later develop severe DHF is very important to choose appropriate intensive supportive therapy since available vaccines for immunization are yet to be approved. Severe dengue responses include T and B cell activation and apoptosis, cytokine storm, hematologic disorders and complement activation. Cytokines, complement and other unidentified factors may transiently act on the endothelium and alter normal fluid barrier function of the endothelial cells and cause plasma leakage. In this review, the host factors such as activated immune and endothelial cells and their products which can be utilized as biomarkers for severe dengue disease are discussed.

Matched MeSH terms: T-Lymphocytes/metabolism*

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