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Biology subjects

Mudd, J. C.

Publications and source records attributed to Mudd, J. C..

4 recordsLinked to original sources

Metabolic reprogramming by caloric restriction enhances acute phase virological control and reduces chronic inflammation in SIV-infected rhesus macaques

Nutrient metabolism influences HIV-1 replication, antiviral immunity, and chronic inflammation, yet is difficult to leverage for therapeutic gain. We sought to modulate metabolism in the non-human primate model of HIV-1 by caloric restriction (CR), a modality canonically known for its antiaging benefits. Four months of 30% CR was safe and resulted in broad and systemic metabolic reprogramming in healthy adult male and female rhesus macaques. Relative to that of ad libitum-fed animals, CR lowered the frequencies of target CCR5+ CD4 T cells in the gut mucosa. Upon infection with SIV, CR reduced acute phase viremia, dampened type I interferon signaling, and overall permitted a more vigorous cycling of CD8+ T cells in lymphoid tissues. CR-induced protection from SIV was associated with a robust up-regulation of glycolysis, which supported an early reduction in viremia that ultimately waned over time. During virologic suppression with antiretroviral therapy (ART), CR significantly limited gastrointestinal (GI) immune activation, improved tricarboxylic acid cycle flux, and lowered concentrations of soluble CD14 and several TNF-related molecules in plasma. Blood SIV DNA levels however were unchanged by CR, suggesting that residual GI dysfunction and inflammation can be decoupled from viral persistence. Our findings highlight that a dietary modality can limit pathology in a primate lentiviral infection. They also reveal the robust but temporally constrained nature of glycolysis in supporting an acute antiviral response. SIGNIFICANCECaloric restriction (CR) is a safe dietary intervention known to confer anti-aging and health benefits across diverse animal models. However, its application in the context of infectious diseases has yielded mixed outcomes and has largely been limited to murine systems. In this study, we therefore employed CR to examine the impact of dietary modulation on SIV infection outcomes. Our findings demonstrate that CR reduced acute-phase viremia and attenuated markers of chronic inflammation following ART, effects that were associated with distinct metabolic signatures. Collectively, these findings underscore the importance of diet and nutrition in shaping chronic viral infection outcomes, such as SIV, within a clinically relevant non-human primate model.

immunology↗

RhCMV Expands CCR5 Memory T Cells and promotes SIV reservoir seeding in the Gut Mucosa

Cytomegalovirus (CMV) is a prevalent {beta}-herpesvirus that persists asymptomatically in immunocompetent hosts. In people with HIV-1 (PWH), CMV is associated with persistence of the HIV-1 reservoir and particular inflammatory related co-morbidities. The true causative role of CMV in HIV-associated pathologies remains unclear given that nearly all PWH are coinfected with CMV. In this study, we examined acute phase SIV dynamics in cohorts of rhesus macaques that were seropositive or -negative for rhesus CMV (RhCMV). We observed expansion of CCR5+ target CD4+ T cells in gut and lymph nodes (LN) that existed naturally in RhCMV-seropositive animals, the majority of which did not react to RhCMV lysate. These cells expressed high levels of the chemokine receptor CXCR3 and a ligand for this receptor, CXCL9, was systemically elevated in RhCMV-seropositive animals. RhCMV+ RMs also exhibited higher peak SIV viremia. CCR5 target memory CD4 T cells in the gut of RhCMV+ RMs were maintained during acute SIV and this was associated with greater seeding of SIV DNA in the intestine. Overall, our data suggests the ability of RhCMV to regulate chemotactic axes that direct lymphocyte trafficking and promote seeding of SIV in a diverse, polyclonal pool of memory CD4+ T cells.

immunology↗

Adjuvant and immunomodulatory potential of Natural Killer T (NKT) activation by NKTT320

Invariant natural killer T-lymphocytes (iNKT) are unique immunomodulatory innate T-cells with an invariant TCR recognizing glycolipids presented on MHC class-I-like CD1d molecules. Activated iNKT rapidly secrete pro-and anti-inflammatory cytokines, potentiate innate and adaptive immunity, and modulate inflammation. Here, we report the effects of in vivo iNKT activation by a novel humanized monoclonal antibody, NKTT320, that binds to the invariant region of the iNKT TCR. NKTT320 led to rapid iNKT activation, increased polyfunctionality, and elevation of multiple plasma analytes within 24 hours of administration. Flow cytometry and RNA-Seq confirmed downstream activation of multiple immune subsets, enrichment of JAK/STAT and PI3K/AKT pathway genes, and upregulation of inflammation-modulating genes CMKLR1, ARG2 and NLRP12. NKTT320 also induced iNKT trafficking to adipose tissue and did not cause iNKT anergy. Our data indicate that NKTT320 has a sustained effect on in vivo iNKT activation, potentiation of innate and adaptive immunity, and resolution of inflammation, which supports its future use as an immunotherapeutic and vaccine adjuvant. SummaryiNKTs are known immunomodulatory cells whose activation is a potential target for immunotherapies and use as an adjuvant. Here we report the potential utility of in vivo iNKT activation using the novel humanized monoclonal antibody NKTT320 for this purpose.

immunology↗

TCF-1 regulates the stem-like memory potential of HIV-specific CD8+ T cells in elite controllers

Although many HIV cure strategies seek to expand HIV-specific CD8+ T cells to control the virus, all are likely to fail if cellular exhaustion is not prevented. A loss in stem-like memory properties (i.e., the ability to proliferate and generate secondary effector cells) is a key feature of exhaustion; little is known, however, about how these properties are regulated in human virus-specific CD8+ T cells. We found that virus-specific CD8+ T cells from humans and non-human primates naturally controlling HIV/SIV infection express more of the transcription factor, TCF-1, than non-controllers. HIV-specific CD8+ T cell TCF-1 expression correlated with memory marker expression and proliferative capacity and declined with antigenic stimulation. CRISPR-Cas9 editing of TCF-1 in human primary T cells demonstrated a direct role in regulating expansion capacity. Collectively, these data suggest that TCF-1 controls the stem-like memory properties of HIV-specific CD8+ T cells and provides a rationale for enhancing this pathway in T cell-based therapeutic strategies for HIV. One Sentence SummaryTCF-1 is highly expressed in HIV-specific CD8+ T cells from elite controllers and directly regulates human CD8+ T cell expansion capacity in response to T cell receptor stimulation.

immunology↗