Allogeneic Memory T Cells Derived from Host DC-Activated CD44loCD8+ T Precursors Sustain Host Tissue Injury of Ongoing Graft-versus-Host Disease.

Abstract Graft-versus-host disease (GVHD) directed against minor histocompatibility antigen (miHAs) evolves over weeks to months, suggesting a requirement for persistent alloreactive donor T cells. In patients with allogeneic bone marrow transplantation (allo-BMT), persistency of GVHD is accompanied with elevated allogeneic CD4+ T cells with memory phenotype in peripheral blood. In contrast, several other studies have recently shown that T cells with memory phenotype (CD44hiCD62Lhi/lo) from normal donor mice do not induce acute GVHD. While these T cells with memory phenotype may be induced by environmental antigenic stimulation or may represent cells undergoing homeostasis in vivo, we found that early activated donor CD44hiCD8+ T cells with effector/memory phenotype upon ex vivo host DC stimulation are also functional defective in GVHD induction in vivo. However, whether alloreactive memory T cells might develop in vivo in recipient with ongoing GVHD, and if this is the case, whether these in vivo generated alloreactive memory T cells may be responsbile for persistency of GVHD, remain unknown. Using the C3H.SW anti-C57BL/6 (B6) and B6 anti-BALB.B mouse models of human GVHD directed against miHAs, we found that alloreactive CD8+ T cells secreting high levels of IFN-γ in recipient mice receiving C3H.SW CD44loCD8+ T cells + T−BM peaked by day 14, declined by day 28, and increased again after 35 days of transplantation, corresponding to the kinetics of primary and memory T cell responses. Indeed, while donor C3H.SW CD8+ T cells recovered from these B6 mice receiving C3H.SW CD44loCD8+ T cells + T−BM 10 days after allo-BMT, at the peak time of primary allogeneic immune response, upregulated the expression of effector marker CD25, donor CD8+ T cells recovered 42 days after allo-BMT from B6 mice with ongoing GVHD, at the time of memory T cell development, expressed high levels of CD44 and CD122 but down-regulated CD25. However, both d10-CD8+ and d42-CD8+ T cells expressed identical levels of cytotoxic molecules including granzyme B, perforin and FasL and were able to kill B6 mouse-derived EL-4 leukemic cells. Compared to naïve CD44loCD8+ T cells that were lost after cultured in the presence of IL-2+IL-15 for 5 days, d42-donor CD8+ T cells recovered from B6 mice with ongoing GVHD survived over 5 days in the presence of IL-2+IL-15 alone and these surviving d42-CD8+ T cells were able to rapidly proliferate in responding to B6 DCs+IL-2+IL-15 in secondary culture. Flow cytometry analysis showed that d42-CD8+ T cells contained at least two distinct subsets: CD44hiCD62Llo (80% to 85%) and CD44hiCD62LhiCD8+(3% to 6%) T cells, resembling to the phenotype of effector memory and central memory CD8+ T cells, respectively. Administration of irradiated secondary B6 mice with either d42-CD44hiCD62Lhi or d42-CD44hiCD62Llo CD8+ T cell subset recovered at day 42 from primary B6 mice receiving C3H.SW CD44loCD8+ T cells + T−BM caused virulent GVHD. These results indicate that alloreactive memory T cells develop in vivo in recipient mice with acute GVHD where host mHAs persist and may be responsible for the persistence of GVHD. Accordingly, we suggest that in vivo blockade of both alloreactive effector and memory T cell responses will be necessary for GVHD prevention and treatment.

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Turnover of MCMV-expanded CD8+ T-cells is similar to that of memory phenotype T-cells and independent of the magnitude of the response

10.1101/2021.11.03.467089 ◽

2021 ◽

Author(s):

Mariona Baliu-Pique ◽

Julia Drylewicz ◽

Xiaoyan Zheng ◽

Lisa Borkner ◽

Arpit C Swain ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Memory T Cells ◽

T Cell Responses ◽

Cd8 T Cell ◽

Ample Evidence ◽

Memory Phenotype ◽

Cell Responses

The potential of memory T-cells to provide protection against re-infection is beyond question. Yet, it remains debated whether long-term T-cell memory is due to long-lived memory cells. There is ample evidence that blood-derived memory phenotype CD8+ T-cells maintain themselves through cell division, rather than through longevity of individual cells. It has recently been proposed, however, that there may be heterogeneity in the lifespans of memory T-cells, depending on factors such as exposure to cognate antigen. Cytomegalovirus (CMV) infection induces not only conventional, contracting T-cell responses, but also inflationary CD8+ T-cell responses, which are maintained at unusually high numbers, and are even thought to continue to expand over time. It has been proposed that such inflating T-cell responses result from the accumulation of relatively long-lived CMV-specific memory CD8+ T-cells. Using in vivo deuterium labelling and mathematical modelling, we found that the average production rates and expected lifespans of mouse CMV-specific CD8+ T-cells are very similar to those of bulk memory-phenotype CD8+ T-cells. Even CMV-specific inflationary CD8+ T-cell responses that differ three-fold in size, were found to turn over at similar rates.

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CD4+ and CD8+ Circulating Memory T Cells Are Crucial in the Protection Induced by Vaccination with Salmonella Typhi Porins

Microorganisms ◽

10.3390/microorganisms9040770 ◽

2021 ◽

Vol 9 (4) ◽

pp. 770

Author(s):

Luis Ontiveros-Padilla ◽

Alberto García-Lozano ◽

Araceli Tepale-Segura ◽

Tania Rivera-Hernández ◽

Rodolfo Pastelin-Palacios ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

T Cell Responses ◽

Salmonella Typhi ◽

Effector Memory ◽

Functional Responses ◽

Memory Phenotype ◽

Memory T Cell ◽

Cell Responses

Salmonella enterica serovar Typhi (S. Typhi) porins, OmpC and OmpF, are potent inducers of the immune response against S. Typhi in mice and humans. Vaccination with porins induces the protection against 500 LD50 of S. Typhi, life-lasting bactericidal antibodies and effector T cell responses in mice; however, the nature of the memory T cell compartment and its contribution to protection remains unknown. In this work, we firstly observed that vaccination with porins induces in situ (skin) CD4+ and CD8+ T cell responses. Analysis of the porin-specific functional responses of skin CD4+ and CD8+ T cells showed IFN-gamma- and IL-17-producing cells in both T cell populations. The memory phenotype of porin-specific T cells indicated the presence of resident and effector memory phenotypes in the skin, and a central memory phenotype in the skin-draining lymph node. In addition, we demonstrated that vaccination with porins via skin reduces the bacterial burden following challenge. Finally, evaluating the role of the circulating T cell memory population in protection, we showed that circulating memory CD4+ and CD8+ T cells are crucial in porin-mediated protection against S. Typhi. Overall, this study highlights the importance of inducing circulating memory T cell responses in order to achieve the optimal protection provided by porins, showing a mechanism that could be sought in the rational development of vaccines.

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Detection of IFNγ-Secreting CD4+ and CD8+ Memory T Cells in COVID-19 Convalescents after Stimulation of Peripheral Blood Mononuclear Cells with Live SARS-CoV-2

Viruses ◽

10.3390/v13081490 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1490

Author(s):

Victoria Matyushenko ◽

Irina Isakova-Sivak ◽

Igor Kudryavtsev ◽

Arina Goshina ◽

Anna Chistyakova ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Memory T Cells ◽

Natural Infection ◽

Intracellular Cytokine Staining ◽

T Cell Responses ◽

Effector Memory ◽

Memory T Cell ◽

Cell Responses ◽

Stimulation Of

Background: New coronavirus SARS-CoV-2, a causative agent of the COVID-19 pandemic, has been circulating among humans since November 2019. Multiple studies have assessed the qualitative and quantitative characteristics of virus-specific immunity in COVID-19 convalescents, however, some aspects of the development of memory T-cell responses after natural SARS-CoV-2 infection remain uncovered. Methods: In most of published studies T-cell immunity to the new coronavirus is assessed using peptides corresponding to SARS-CoV-1 or SARS-CoV-2 T-cell epitopes, or with peptide pools covering various parts of the viral proteins. Here, we determined the level of CD4+ and CD8+ memory T-cell responses in COVID-19 convalescents by stimulating PBMCs collected 1 to 6 months after recovery with sucrose gradient-purified live SARS-CoV-2. IFNγ production by the central and effector memory helper and cytotoxic T cells was assessed by intracellular cytokine staining assay and flow cytometry. Results: Stimulation of PBMCs with live SARS-CoV-2 revealed IFNγ-producing T-helper effector memory cells with CD4+CD45RA−CCR7− phenotype, which persisted in circulation for up to 6 month after COVID-19. In contrast, SARS-CoV-2-specific IFNγ-secreting cytotoxic effector memory T cells were found at significant levels only shortly after the disease, but rapidly decreased over time. Conclusion: The stimulation of immune cells with live SARS-CoV-2 revealed a rapid decline in the pool of effector memory CD8+, but not CD4+, T cells after recovery from COVID-19. These data provide additional information on the development and persistence of cellular immune responses after natural infection, and can inform further development of T cell-based SARS-CoV-2 vaccines.

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CXCR3 Is Required for the Efficient Recruitment of Bone Marrow-Resident Memory T Cells to Inflamed Tissues,

Blood ◽

10.1182/blood.v118.21.3242.3242 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3242-3242

Author(s):

Robbert van der Voort ◽

Claudia Brandao ◽

Thomas J. Volman ◽

Viviènne Verweij ◽

Klaas van Gisbergen ◽

...

Keyword(s):

Bone Marrow ◽

T Cells ◽

T Cell ◽

Immune Responses ◽

Cd8 T Cells ◽

Memory T Cells ◽

Central Memory ◽

T Cell Subsets ◽

Effector Memory ◽

Memory T Cell

Abstract Abstract 3242 Although the importance of the bone marrow (BM) in hematopoiesis is well known, its function in adaptive immune responses has only recently been acknowledged. Currently it is known that the BM contains fully functional CD4+ and CD8+ T cells that can engage in both primary and secondary immune responses. Interestingly, most of these T cells belong to the memory T cell lineage, identifying the BM as one of the largest memory T cell reservoirs in the body. Since not much is known about the trafficking of BM T cells, we compared the homing phenotype and function of T cell subsets in the BM, blood, spleen and peripheral lymph nodes (pLN). In addition, we determined the expression of chemokine mRNA and protein levels in the BM and other lymphoid organs. We confirmed that at least 80% of the CD4+ and 60% of the CD8+ BM T cells have a memory phenotype, and that most CD4+ T cells belong to the effector memory lineage, while the CD8+ population predominantly consists of central memory T cells. Most BM T cells expressed the chemokine receptor CXCR3, the adhesion molecules P-selectin glycoprotein ligand 1 and VLA-4, and increased levels of CD44 and LFA-1, as compared to T cells from the spleen. In addition, L-selectin was absent from most CD4+ BM T cells, but present on virtually all CD8+ T cells. Notably, the percentage of CXCR3+ T cells within the effector memory and central memory subsets from BM was higher than within the same subsets from pLN. Furthermore, BM contained significant mRNA levels of the CXCR3 ligands CXCL9, CXCL10 and CXCL11. An in vivo migration assay using a mixture of fluorescent-labeled T cells from CXCR3-deficient mice and control mice indicated however that during homeostasis CXCR3 does not play a major role in BM entry or retention. These data suggest that CXCR3 expressed by memory T cells is rather involved in BM exit, than in BM entry. Indeed, we observed that, as compared to control mice, CXCR3−/− mice contained significantly more CD4+ and CD8+ T cells in their BM. Additional in vitro assays demonstrated that CD4+ and CD8+ BM T cells migrated vigorously in response to CXCL9 and CXCL10, generally released in high concentrations during inflammation. Finally, we demonstrate that CXCR3−/− effector/effector memory T cells, but not wild type T cells, accumulate in the BM of mice infected with lymphocytic choriomeningitis virus. Altogether, these data demonstrate that the BM is a major reservoir of memory T cells that employ CXCR3 to quickly respond to chemotactic signals from inflamed tissues. Disclosures: No relevant conflicts of interest to declare.

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A Comparison of Human CMVpp65-Specific Central Memory and Effector Memory CD8 T-Cells When Stimulated in-Vivo with IL-2 or IL-15/IL-15Rα Complex in a Murine Xenograft Model of Adoptive Cell Therapy

Blood ◽

10.1182/blood.v124.21.4805.4805 ◽

2014 ◽

Vol 124 (21) ◽

pp. 4805-4805

Author(s):

Tzu-Yun Kuo ◽

Aisha Hasan ◽

Richard J O'Reilly

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Adoptive Immunotherapy ◽

Memory T Cells ◽

Cd8 T Cell ◽

Central Memory ◽

Effector Memory ◽

Cell Clones

Abstract Initial clinical trials of adoptive immunotherapy have shown that the efficacy of adoptively transferred T-cells in man is often limited by the failure of cultured T cells, particularly cloned CD8 T cells, to persist in vivo. These studies demonstrated that the transferred T cells induced only transient responses and that persistence of the transferred T-cell clonotypes correlated with disease regression. A previous study suggested that CMV virus-specific CD8 T cell clones derived from central memory T cells (TCM), but not effector memory T cells (TEM), persisted long-term in non-human primates. On the other hand, another study comparing TCM and TEM derived SIV virus specific CD8 T-cell clones that were adoptively transferred in non-human primates demonstrated limited persistence of both TCM and TEM derived transferred T cells, and failed to show any difference between the two cell types. Because of these conflicting data, we have reexamed the persistence of adoptively transferred viral antigen specific T-cells derived from TCM and TEM population. Accordingly, we developed a NOG mouse model for studying the ability of human CMVpp65-specific T cells derived from central memory and effector memory populations to migrate to and accumulate in human tumor xenografts expressing CMVpp65, to alter the growth of these tumors and to persist in the tumors. This model also allows us to test immunomodulating agents and their ability to enhance targeted T-cell accumulations, antitumor activity and persistence. We analyzed CMVpp65-specific CD8 T cells derived from TCM and TEM precursors in vitro and in vivo. To tract the T-cells in vivo, we transduced membrane-bound Gaussia luciferase into TCM and TEM populations and monitored T cell trafficking by in vivo bioluminescence. Contrary to expectation, our results initially showed no differences between TCM and TEM derived CMVpp65-specific T-cell in mice co-treated with IL-2 in the time to accumulation, ultimate level of accumulation, degree of CMVpp65+ tumor regression or T-cell persistence. However, in mice cotreated with IL-15/IL-15Rα complex, both TCM and TEM exhibited more sustained engraftment and more prolonged accumulation in both the targeted tumor and in the marrow. In mice treated with IL-15/IL-15Rα, TCM and TEM derived T cells showed a similar effector memory phenotype and a similar level of regression of tumor growth. Thus, adoptive transfer of CMVpp65 specific TCM or TEM when combined with IL-15/IL-15Rα complex may support better persistence of antigen-specific T-cells following adoptive immunotherapy. Studies comparing IL-15/IL-15Rα complex with IL-15 alone are in progress. Disclosures No relevant conflicts of interest to declare.

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Variances in Antiviral Memory T-Cell Repertoire of CD45RA- and CD62L-Depleted Lymphocyte Products Reflect the Need of Individual T-Cell Selection Strategies to Reduce the Risk of GvHD while Preserving Antiviral Immunity in Adoptive T-Cell Therapy

Transfusion Medicine and Hemotherapy ◽

10.1159/000516284 ◽

2021 ◽

pp. 1-14

Author(s):

Caroline Mangare ◽

Sabine Tischer-Zimmermann ◽

Agnes Bonifacius ◽

Sebastian B. Riese ◽

Anna Christina Dragon ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Memory T Cells ◽

Cell Activity ◽

T Cell Responses ◽

Adoptive T Cell Therapy ◽

Effector Memory ◽

Hematopoietic Stem ◽

Memory T Cell ◽

Cell Responses

Introduction: Viral infections and reactivations still remain a cause of morbidity and mortality after hematopoietic stem cell transplantation due to immunodeficiency and immunosuppression. Transfer of unmanipulated donor-derived lymphocytes (DLI) represents a promising strategy for improving cellular immunity but carries the risk of graft versus host disease (GvHD). Depleting alloreactive naïve T cells (TN) from DLIs was implemented to reduce the risk of GvHD induction while preserving antiviral memory T-cell activity. Here, we compared two TN depletion strategies via CD45RA and CD62L expression and investigated the presence of antiviral memory T cells against human adenovirus (AdV) and Epstein-Barr virus (EBV) in the depleted fractions in relation to their functional and immunophenotypic characteristics. Methods: T-cell responses against ppEBV_EBNA1, ppEBV_Consensus and ppAdV_Hexon within TN-depleted (CD45RA−/CD62L−) and TN-enriched (CD45RA+/CD62L+) fractions were quantified by interferon-gamma (IFN-γ) ELISpot assay after short- and long-term in vitro stimulation. T-cell frequencies and immunophenotypic composition were assessed in all fractions by flow cytometry. Moreover, alloimmune T-cell responses were evaluated by mixed lymphocyte reaction. Results: According to differences in the phenotype composition, antigen-specific T-cell responses in CD45RA− fraction were up to 2 times higher than those in the CD62L− fraction, with the highest increase (up to 4-fold) observed after 7 days for ppEBV_EBNA1-specific T cells. The CD4+ effector memory T cells (TEM) were mainly responsible for EBV_EBNA1- and AdV_Hexon-specific T-cell responses, whereas the main functionally active T cells against ppEBV_Consensus were CD8+ central memory T cells (TCM) and TEM. Moreover, comparison of both depletion strategies indicated that alloreactivity in CD45RA− was lower than that in CD62L− fraction. Conclusion: Taken together, our results indicate that CD45RA depletion is a more suitable strategy for generating TN-depleted products consisting of memory T cells against ppEBV_EBNA1 and ppAdV_Hexon than CD62L in terms of depletion effectiveness, T-cell functionality and alloreactivity. To maximally exploit the beneficial effects mediated by antiviral memory T cells in TN-depleted products, depletion methods should be selected individually according to phenotype composition and CD4/CD8 antigen restriction. TN-depleted DLIs may improve the clinical outcome in terms of infections, GvHD, and disease relapse if selection of pathogen-specific donor T cells is not available.

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Adoptive Immunotherapy with Memory T Cells.

Blood ◽

10.1182/blood.v112.11.sci-25.sci-25 ◽

2008 ◽

Vol 112 (11) ◽

pp. sci-25-sci-25 ◽

Cited By ~ 1

Author(s):

Helen E. Heslop

Keyword(s):

T Cells ◽

T Cell ◽

Memory T Cells ◽

Ex Vivo ◽

Central Memory ◽

Effector Memory ◽

Memory Phenotype ◽

Effector Memory T Cells ◽

Effector Memory Cells

Clinical adoptive cellular immunotherapy of malignancy and viral infection should transfer T cells that expand in vivo on exposure to antigen and can enter the memory compartment to persist long-term. A number of factors, including cellular phenotype, influence the behavior of the infused line. Primate studies have shown that antigen-specific CD8+ T cell clones only persisted long-term in vivo if they were derived from central memory T cells, but not from effector memory T cells, reacquiring phenotypic and functional properties of memory T cells.1 Other studies have suggested that adoptive transfer of ex vivo-expanded effector memory T cells will have poor survival and clinical efficacy, reporting instead that less differentiated T cells with longer telomeres exhibit longer persistence. These data imply that prolonged ex vivo expansion, required, for example, for T cell cloning, adversely affects subsequent in vivo expansion and survival. However, our trials administering ex vivo-expanded, polyclonal EBV-specific T cell lines demonstrated that expanded effector memory T cells, infused into a lymphodepleted host, can expand massively in vivo, enter the memory compartment, and persist for up to seven years after infusion. Furthermore, in a study infusing trivirus-specific CTLs with effector memory phenotype, we saw expansion of CTLs specific for the latent viruses CMV and EBV. By contrast, adenoviral-specific CTL persisted only in patients who were acutely infected with the agent2 We recently compared non-specifically activated T cells (ATC) with EBV-specific CTLs derived from the same initial peripheral blood collection and expressing distinguishable chimeric GD2-specific chimeric antigen receptors (CARATC and CAR-CTL). In this study, ATCs were cultured for 14 to 21 days. Between 0.9% and 6.1% retained a central memory (CCR7+, CD62L+) phenotype, up to 30% had an effector memory phenotype (CCR7−, CD62L+), and the remainder had a terminally/fully differentiated effector phenotype. By contrast, EBV-CTL were cultured for 30 to 44 days and expressed no CCR7, but up to 50% were CD62L+, and contained cells that were terminally/fully differentiated effectors and effector memory cells. These EBV-CTLs also all had a CD45RO memory phenotype, while about 13% to 60% of ATCs expressed CD45RA, a marker of naïve T cells. Despite these differences in memory subsets, it was the CAR-CTLs that had the clearly greater persistence and could be shown to retain functionality, while CAR-ATC rapidly disappeared from the circulation and could not be recovered. Hence, factors other than phenotype, such as antigenic stimulation and costimulation almost certainly influence cell fate after infusion, and determine whether or not effector memory cells can re-access the central memory pool. Ultimately, strategies that combine selection of optimal phenotype with the provision of antigen stimulation and co-stimulation and a cytokine milieu that favors homeostatic expansion will likely lead to the most effective outcomes following adoptive T cell transfer.

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Off-target effects of Cre recombinase reveal limits of adoptive T cell transfers and persistent proliferation of effector CD8 T-cells

10.1101/502666 ◽

2018 ◽

Author(s):

Lisa Borkner ◽

Anja Drabig ◽

Xiaoyan Zheng ◽

Julia Drylewicz ◽

Thomas Marandu ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

Adoptive Transfer ◽

Memory T Cells ◽

Murine Cytomegalovirus ◽

Effector Memory ◽

Latently Infected ◽

The One

Effector-memory T-cells (TEM) are assumed to be short-lived cells that poorly proliferate upon antigenic restimulation, thus depending on central-memory T-cells (TCM) to replenish their numbers during homeostasis, largely depending on adoptive transfer evidence. Here we analyzed T cells in their natural environment and observed robust long-term in vivo cycling within the TEM subset that was stronger than the one in the TCM subset. We compared the non-persistent vaccinia virus and the persisting murine Cytomegalovirus (MCMV), which induces inflationary TEM responses that remain high during viral latency. We analyzed Ki67 expression during acute, resolved and latent infection and found Ki67hiBcl2lo TEM in acutely or latently infected mice, arguing for antigen-driven TEM proliferation. In vivo labeling with deuterium showed that TEM acquired deuterium more rapidly than TCM, and were rapidly lost during chase. Similarly, antibody-mediated depletion of primed CD8 T cells in latenly infected mice revealed that TEM replenished more rapidly than TCM, suggesting that TEM cycle faster than TCM. Finally, we utilized the ability of Tamoxifen-induced Cre-ERT2 recombinase to induce chromosomal translocations when large amounts of Tamoxifen are administered for an extended time, which resulted in a selective depletion of proliferating Ki67hi cells that hardly affected the TCM subset, but drove a selective loss of Ki67hiBcl2lo effector T-cells, and an increase in the death of TEM in the spleen, arguing that TEM preferentially proliferate in the spleen. Since our results contradicted previous evidence from adoptive transfer experiments, we tested T cell homing to the spleen upon adoptive transfer. TEM homing was substantially poorer than the one of TCM, likely explaining the previously reported expansions of TCM, but not TEM, upon transfer into latently infected mice. In conclusion, our data suggest that memory inflation is largely maintained by splenic proliferation of antigen-specific TEM, rather than by continued expansion and differentiation of TCM.

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Adrenergic signaling controls early transcriptional programs during CD8+ T cell responses to viral infection

10.1101/2021.10.20.465178 ◽

2021 ◽

Author(s):

Leonardo Estrada ◽

Didem Agac Cobanoglu ◽

Aaron Wise ◽

Robert Maples ◽

Murat Can Cobanoglu ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cd8 T Cells ◽

T Cell Responses ◽

Cd8 T Cell ◽

Receptor Activation ◽

Cell Development ◽

Primary Response ◽

Cell Responses

Viral infections drive the expansion and differentiation of responding CD8+ T cells into variegated populations of cytolytic effector and memory cells. While pro-inflammatory cytokines and cell surface immune receptors play a key role in guiding T cell responses to infection, T cells are also markedly influenced by neurotransmitters. Norepinephrine is a key sympathetic neurotransmitter, which acts to suppress CD8 + T cell cytokine secretion and lytic activity by signaling through the beta2-adrenergic receptor (ADRB2). Although ADRB2 signaling is considered generally immunosuppressive, its role in regulating differentiation of effector T cells in response to infection has not been investigated. Using an adoptive transfer approach, we compared the expansion and differentiation of wild type (WT) to Adrb2-/- CD8 + T cells throughout the primary response to vesicular stomatitis virus (VSV) infection in vivo. We measured the dynamic changes in transcriptome profiles of antigen-specific CD8 + T cells as they responded to VSV. Within the first 7 days of infection, WT cells out-paced the expansion of Adrb2-/- cells, which correlated with reduced expression of IL-2 and the IL-2Ralpha; in the absence of ADRB2. RNASeq analysis identified over 300 differentially expressed genes that were both temporally regulated following infection and selectively regulated in WT vs Adrb2-/- cells. These genes contributed to major transcriptional pathways including cytokine receptor activation, signaling in cancer, immune deficiency, and neurotransmitter pathways. By parsing genes within groups that were either induced or repressed over time in response to infection, we identified three main branches of genes that were differentially regulated by the ADRB2. These gene sets were predicted to be regulated by specific transcription factors involved in effector T cell development, such as Tbx21 and Eomes. Collectively, these data demonstrate a significant role for ADRB2 signaling in regulating key transcriptional pathways during CD8 + T cells responses to infection that may dramatically impact their functional capabilities and downstream memory cell development.

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