scholarly journals Proteomics Analysis of Three Different Strains of Mycobacterium tuberculosis under In vitro Hypoxia and Evaluation of Hypoxia Associated Antigen’s Specific Memory T Cells in Healthy Household Contacts

2016 ◽  
Vol 7 ◽  
Author(s):  
Santhi Devasundaram ◽  
Akilandeswari Gopalan ◽  
Sulochana D. Das ◽  
Alamelu Raja
Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2024-2024
Author(s):  
MD Muharrem Muftuoglu ◽  
Abdullah Alsuliman ◽  
Ahmad Khoder ◽  
Yong-Oon Ahn ◽  
Enli Liu ◽  
...  

Abstract CD4+ T cells are important in the establishment of long-lived pathogen-specific immunity. However, the mechanisms by which antigen specific CD4 T resist insult by lymphocytotoxic agents and are sustained long-term is not well defined. A recent report described the existence of a subset of long-lived CD8+ memory T cells with stem-like properties (Turtle et al, 2009), including the ability to efflux cellular toxins through the ABC–superfamily multidrug efflux protein ABCB1. We hypothesized that a similar subset of T cells with drug-effluxing properties also exists within the CD4+ T cell compartment. We used multiparameter flow cytometry to measure the capacity of CD4+ T cells from donors to efflux the fluorescent substrate Rh123. We identified a subset of memory CD4+ T cells with rapid drug-effluxing ability, defined as CD161+CD95+CD45RA-CD127hiCD28+CD25int that shared remarkable phenotypic similarity to CD8+drug-effluxing memory T cells. The stem cell marker c-kit was preferentially expressed on Rh123 effluxing CD4+CD161+ T cells, whereas CD57, a marker of terminal differentiation, was exclusively expressed on non-effluxing CD4+CD161+ T cells. Rh123 effluxing CD4+CD161+ T cells also displayed differential expression of CD31, CD38, CD58, CD122 and IL-18RA. Rh123 effluxing CD4+ CD161+ T cells were undetectable in cord blood, but found in adult blood, consistent with the emergence of this subset of memory T cells as a consequence of antigen exposure during childhood and adult life. We reasoned that this subset may be enriched within the viral-specific T cell repertoire. Indeed, CMV-specific CD4+ T cells were found to share the same phonotypic markers as Rh123 effluxing CD4+CD161+ T cells. We purified CMV-specific CD4+ T cells using the interferon gamma capture assay (Miltenyi), and showed that CMV-enriched CD4+T cells preferentially and rapidly efflux Rh123. The high ABCB1-mediated drug efflux capacity of CD4+ CD161+ memory cells also facilitated their in vitro resistance to daunorubicin, which was abrogated by competitive inhibitors of ABCB1. In keeping with the in vitro data, we found a significant increase in the frequencies of CMV-specific CD4+ T cells in the peripheral blood of patients with AML after recovery from remission induction chemotherapy, suggesting that CMV-specific CD4+ T cells can preferentially survive and proliferate following chemotherapy. Since interleukin (IL)-7 and IL-15 drive the proliferation of T cells during lymphopenia to restore homeostasis, we assessed the response of CD4+CD161+ T cells to stimulation with CD3/CD28 +IL7 and IL15. Both effluxing and non-effluxing sort-purified central and effector memory CD4+CD161+ T cells proliferated and upregulated Ki67 in vitro. Whereas CD4+CD161+ T cells were able to differentiate into CD4+CD161- T cells, a subset retained CD161 expression. These data suggest that although CD4+CD161+ T cells share phenotypic similarities with terminally differentiated cells, they are able to fully proliferate, differentiate to CD161-ve cells and self-renew to preserve the pool of memory T cells CD161 is also a hallmark of Th17 cells. We examined the cytokine profile of CD4+CD161+ T cells stimulated with a pool of overlapping MHC class II CMV pp65 peptides. After 6 and 24 hrs of in vitro stimulation we failed to detect significant IL-17 production. Furthermore, by real time qPCR, the Th1 transcription factor Tbet, rather than RORC2 (a Th17 hallmark), was found to be preferentially expressed in CMV enriched CD4+CD161+ T cells, indicating that CMV-specific CD4+CD161+T cells in fact represent a unique subset of Th1 cells, distinct from Th17 cells. Our data delineate novel findings related to a distinct subset of drug-effluxing CD4+CD161+ viral-specific memory T cells. Signaling pathways leading to CD4+CD161+ABCB1+ differentiation, the role of this subset in drug resistance and the presence or absence of “stemness” which may impart this subset with extended longevity are being explored. †Muharrem Muftuoglu and Abdullah Alsuliman contributed equally to this work. Disclosures: No relevant conflicts of interest to declare.


Author(s):  
Stefanie Herda ◽  
Andreas Heimann ◽  
Benedikt Obermayer ◽  
Elisa Ciraolo ◽  
Stefanie Althoff ◽  
...  

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A120-A120
Author(s):  
Sashi Kasimsetty ◽  
Himavanth Gatla ◽  
Dhana Chinnasamy

BackgroundMCY-M11, an anti-mesothelin CAR (Meso-CAR) mRNA transfected PBMC cell product manufactured through <1 day-process is under clinical evaluation for the treatment of advanced ovarian cancer and peritoneal mesothelioma. In this in-vitro study, we characterized the phenotypic and functional status of immune cell populations in MCY-M11 and their possible role in antitumor immunity.MethodsMCY-M11 cell product were generated using unmanipulated healthy donor PBMCs (n=5) by transfection of Meso-CAR mRNA using MaxCyte’s proprietary Flow Electroporation® system. Frozen MCY-M11 cell product was thawed and cultured for 18 hours, then co-cultured with hMSLNneg or hMSLNpos human mesothelioma cell line, MSTO-211H, or stimulated with anti-CD3/anti-CD28 antibodies in vitro for 8 days. Distinct cell populations in MCY-M11 were evaluated for kinetics and duration of CAR expression, differentiation, activation, exhaustion, and their ability to secrete various immunomodulatory molecules during in vitro stimulation. Antigen-specific proliferation and cytotoxicity of MCY-M11 against hMSLNpos tumor cells as well as their ability to mount long-term antitumor immunity through epitope spreading mechanisms were studied.ResultsIndividual cell populations in MCY-M11 exhibited a consistent but transient Meso-CAR expression persisting for about 7 days. Cell subsets in MCY-M11 acquired early signs of activation and differentiation within 18–24 hours post-culture, but only attained full activation and lineage-specific differentiation upon specific response to hMSLNpos tumor cells. hMSLN antigen experienced MCY-M11 retained significant fractions of Naïve and Central Memory T cells and increased percentage of Effector Memory T cells along with increased expression of CD62L, CD27, and chemokine receptors (CCR5, CCR7, and CXCR3). MCY-M11 exhibited strong antigen-specific cytotoxicity against hMSLNpos tumor cells with corresponding increase in activation and proliferation of CD4+ and CD8+ T cell subsets and displayed low or no acquisition of known exhaustion markers. NK cells also exhibited a functionally superior molecular signature exhibiting increased levels of NKG2D, NKp44, NKp46, FAS, and TRAIL. The Monocytes and B cells in MCY-M11 also acquired an activated, differentiated, and mature phenotype, expressing molecules required for antigen presentation (HLA-DR, HLA-ABC, and CD205) and T cell co-stimulation (CD80 and CD86) to mount a strong antitumor response. These phenotypic changes in cell subsets of MCY-M11 transpired with simultaneous secretion of potent immunostimulatory molecules and chemokines facilitating an extended antitumor response through epitope spreading.ConclusionsWe demonstrated that MCY-M11 is a unique cell product possessing a complete built-in immune cellular machinery with favorable phenotype and enhanced functions specialized in mediating an effective and long-term antitumor response.Trial RegistrationNCT03608618


1992 ◽  
Vol 176 (2) ◽  
pp. 575-579 ◽  
Author(s):  
W T Lee ◽  
E S Vitetta

We have used staphylococcal enterotoxin B (SEB) to study the role of naive and memory T cells in the induction of peripheral tolerance. After administration of SEB to mice, the numbers of naive and memory T cells increase, as does the proportion of memory T cells, which are unresponsive to further stimulation with SEB in vitro. In addition, memory T cells generated in response to conventional antigen, which proliferate and provide help to B cells in the presence of the conventional antigen, fail to respond to superantigen. Hence, memory T cells, in general, are anergized by SEB. These results suggest that SEB-induced activation and anergy reflect the combined responses of naive and memory T cells. The differential activation vs. anergy of naive and memory T cells by superantigen may be related to cytokine production and may play an important role in the etiology of autoimmune diseases or immunodeficiency diseases such as acquired immune deficiency syndrome.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ya-fei Qin ◽  
De-jun Kong ◽  
Hong Qin ◽  
Yang-lin Zhu ◽  
Guang-ming Li ◽  
...  

BackgroundChronic rejection characterized by chronic allograft vasculopathy (CAV) remains a major obstacle to long-term graft survival. Due to multiple complicated mechanisms involved, a novel therapy for CAV remains exploration. Although mesenchymal stromal cells (MSCs) have been ubiquitously applied to various refractory immune-related diseases, rare research makes a thorough inquiry in CAV. Meanwhile, melatonin (MT), a wide spectrum of immunomodulator, plays a non-negligible role in transplantation immunity. Here, we have investigated the synergistic effects of MT in combination with MSCs in attenuation of CAV.MethodsC57BL/6 (B6) mouse recipients receiving BALB/c mouse donor aorta transplantation have been treated with MT and/or adipose-derived MSCs. Graft pathological changes, intragraft immunocyte infiltration, splenic immune cell populations, circulating donor-specific antibodies levels, cytokine profiles were detected on post-operative day 40. The proliferation capacity of CD4+ and CD8+ T cells, populations of Th1, Th17, and Tregs were also assessed in vitro.ResultsGrafts in untreated recipients developed a typical pathological feature of CAV characterized by intimal thickening 40 days after transplantation. Compared to untreated and monotherapy groups, MT in combination with MSCs effectively ameliorated pathological changes of aorta grafts indicated by markedly decreased levels of intimal hyperplasia and the infiltration of CD4+ cells, CD8+ cells, and macrophages, but elevated infiltration of Foxp3+ cells. MT either alone or in combination with MSCs effectively inhibited the proliferation of T cells, decreased populations of Th1 and Th17 cells, but increased the proportion of Tregs in vitro. MT synergized with MSCs displayed much fewer splenic populations of CD4+ and CD8+ T cells, Th1 cells, Th17 cells, CD4+ central memory T cells (Tcm), as well as effector memory T cells (Tem) in aorta transplant recipients. In addition, the percentage of splenic Tregs was substantially increased in the combination therapy group. Furthermore, MT combined with MSCs markedly reduced serum levels of circulating allospecific IgG and IgM, as well as decreased the levels of pro-inflammatory IFN-γ, TNF-α, IL-1β, IL-6, IL-17A, and MCP-1, but increased the level of IL-10 in the recipients.ConclusionsThese data suggest that MT has synergy with MSCs to markedly attenuate CAV and provide a novel therapeutic strategy to improve the long-term allograft acceptance in transplant recipients.


2020 ◽  
Vol 22 (5) ◽  
pp. 837-846
Author(s):  
E. A. Blinova ◽  
A. V. Kolerova ◽  
V. E. Balyasnikov ◽  
V. A. Kozlov

IL-7 is a key factor for the survival and maintenance of CD4+ central (Tcm) and effector (Tem) memory cells in the whole body. In many autoimmune diseases, an elevated level of IL-7 is detected in blood serum and at the site of inflammation, thus suggesting participation of this homeostatic factor in the survival of memory T cells, including auto-reactive clones, in inflammatory disorders. The aim of the study was to investigate the mechanisms of maintaining CD4+ memory T cells under normal and inflammatory conditions. We developed an in vitro model of inflammation, based on induction of pro-inflammatory cytokines, and then evaluated the effects of IL-7 upon purified sorted populations of CD4+Tcm and Tem under normal conditions and in vitro inflammatory model. IL-7 treatment promoted maintenance of CD4+Tcm phenotype in all variants of cultures. In the absence of contact with adherent cell fraction, the IL-7-induced proliferation of Tcm and Tem was slightly reduced, both under normal and inflammatory conditions, thus suggesting low sensitivity of memory T cells to contacts with MHC, and, probably, a requirement for additional signals to provide complete stimulation with IL-7. The last suggestion is also supported by data about CD127 and CD132 expression, i.e., in the absence of contact with MHC, the proportion of CD127+CD132+ cells was decreased in both subpopulations of CD4+ memory cells. Upon in vitro cultures, IL-7 contributed to decreased expression of CD127, and increased expression of CD132 on CD4+Tcm and Tem. We have evaluated the CD4+Tcm and Tem populations by affinity of T cell receptor (TCR), using the level of CD5 expression. Т cells with high TCR affinity for self-antigens are known to have higher expression of CD5. In comparison to Tem, the Tcm contained more CD5high cells. In cultures, IL-7 promoted a high level of CD5 expression on Tcm, which was comparable to levels observed in peripheral blood cells. High CD5 expression on Tem was observed after stimulation with IL-7 in the in vitro inflammatory model. In the absence of contact with MHC, the number of CD5high cells decreased among CD4+Tem and Tcm. Thus, CD4+Tcm cells with high affinity for autologous antigens are probably dependent on the presence of homeostatic factors, in particular, IL-7, and contacts with antigen-presenting cells (APCs). Under conditions of inflammation, no changes were revealed in the mechanism of maintaining CD4+Tcm, in contrast to CD4+Tem. Being less dependent on IL-7 under normal conditions, CD4+CD5highTem are accumulated in the presence of IL-7 under in vitro inflammatory conditions.


2017 ◽  
Vol 63 (6) ◽  
pp. 539-545 ◽  
Author(s):  
M.B. Rayev ◽  
S.A. Zamorina ◽  
L.S. Litvinova ◽  
K.A. Yurova ◽  
O.G. Khaziakhmatova ◽  
...  

The effects of chorionic gonadotropin (hCG) on the expression of the hTERT gene in combination with the conversion of the phenotype of naive T-cells and T-cells of immune memory in vitro were studied. hCG inhibited expression of hTERT mRNA in naive T-cells (CD45RA+) and immune memory T cells (CD45RO+), causing a decrease in the replicative potential of the cells. The presence of hCG in the culture led to the conversion of the phenotype of T-lymphocytes. hCG reduced the number of proliferating T-cells of immune memory, estimated by phenotypic signs by differential gating. hCG (10 IU/ml and 100 IU/ml) inhibited expression of CD25 by the studied populations, but did not modulate expression of the CD71 proliferation marker. Thus, hCG inhibited the functional activity of naive T-cells and T-cells of immune memory, which, in the context of pregnancy, can contribute to the formation of immune tolerance to the semi-allogenic fetus.


2004 ◽  
Vol 78 (13) ◽  
pp. 7284-7287 ◽  
Author(s):  
Michaela Lucas ◽  
Cheryl L. Day ◽  
Jessica R. Wyer ◽  
Sharon L. Cunliffe ◽  
Andrew Loughry ◽  
...  

ABSTRACT Recent advances in class II tetramer staining technology have allowed reliable direct ex vivo visualization of antigen-specific CD4 T cells. In order to define the frequency and phenotype of a prototype response to a nonpersistent pathogen, we have used such techniques to analyze influenza virus-specific memory CD4 T cells directly from blood. These responses are stably detectable ex vivo at low frequencies (range, 0.00012 to 0.0061% of CD4 T cells) and display a distinct “central memory” CD62L+ phenotype.


2020 ◽  
Vol 5 (54) ◽  
pp. eabc6373
Author(s):  
Qing Zhao ◽  
Lennard W. Duck ◽  
Fengyuan Huang ◽  
Katie L. Alexander ◽  
Craig L. Maynard ◽  
...  

Microbiota-reactive CD4+ T memory (TM) cells are generated during intestinal infections and inflammation, and can revert to pathogenic CD4+ T effector (TE) cells, resulting in chronicity of inflammatory bowel disease (IBD). Unlike TE cells, TM cells have a low rate of metabolism unless they are activated by reencountering cognate antigen. Here, we show that the combination of cell activation and metabolic checkpoint inhibition (CAMCI), by targeting key metabolic regulators mTORC and AMPK, resulted in cell death and anergy, but enhanced the induction of the regulatory subset. Parenteral application of this treatment with a synthetic peptide containing multiple flagellin T cell epitopes (MEP1) and metabolic inhibition successfully prevented the development of CD4+ T cell–driven colitis. Microbiota-specific CD4+ T cells, especially the pathogenic TE subsets, were decreased 10-fold in the intestinal lamina propria. Furthermore, using the CAMCI strategy, we were able to prevent antigen-specific TM cell formation upon initial antigen encounter, and ablate existing TM cells upon reactivation in mice, leading to an altered transcriptome in the remaining CD4+ T cells after ablation. Microbiota flagellin–specific CD4+ T cells from patients with Crohn’s disease were ablated in a similar manner after CAMCI in vitro, with half of the antigen-specific T cells undergoing cell death. These results indicate that parenteral activation of microbiota-specific CD4+ T cells with concomitant metabolic inhibition is an effective way to ablate pathogenic CD4+ TM cells and to induce T regulatory (Treg) cells that provide antigen-specific and bystander suppression, supporting a potential immunotherapy to prevent or ameliorate IBD.


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