Lack of Differences in Inflammation and T Cell-Mediated Function between Young and Older Women with Obesity

Both obesity and aging are associated with dysregulated immune and inflammatory responses. There is limited knowledge, however, on differences in the immune system between young and older adults with obesity. The goal of this study was to compare circulating inflammatory cytokines and T cell-mediated immune response between young and older women with obesity. Twenty-three young (23–43 years) and 21 older (60–83 years) women with obesity were recruited at the Weight and Wellness Center at Tufts Medical Center. Circulating inflammatory cytokines (CRP, IL-6, and IL-1β) and ex vivo indicators of T cell-mediated immune function were compared between the groups. Older women with obesity had significantly fewer circulating CD3+, CD8+, CD19+, and natural killer T (NKT) cells compared to young women with obesity (p = 0.016, p < 0.0001, p = 0.0003, and p < 0.0001, respectively). However, with few exceptions, there was no significant difference in inflammation markers or stimulated lymphocyte proliferation and cytokine production by peripheral blood mononuclear cells between young and older participants. These findings are in contrast to those previously reported in young and old subjects with healthy weight and call for further investigation into the impact of obesity on premature aging of the immune system.

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Cytokine Overproduction and Immune System Dysregulation in alloHSCT and COVID-19 Patients

Frontiers in Immunology ◽

10.3389/fimmu.2021.658896 ◽

2021 ◽

Vol 12 ◽

Author(s):

Andrzej Lange ◽

Janusz Lange ◽

Emilia Jaskuła

Keyword(s):

Immune System ◽

Adaptive Immunity ◽

Inflammatory Cytokines ◽

Cytokine Production ◽

Conditioning Regimen ◽

Laboratory Data ◽

Hematopoietic Stem ◽

Post Transplant ◽

Sequence Of Events ◽

The Impact

The COVID-19 pathomechanism depends on (i) the pathogenicity of the virus, (ii) ability of the immune system to respond to the cytopathic effect of the virus infection, (iii) co-morbidities. Inflammatory cytokine production constitutes a hallmark of COVID-19 that is facilitated by inability of adaptive immunity to control virus invasion. The effect of cytokine release syndrome is deleterious, but the severity of it depends on other confounding factors: age and comorbidities. In this study, we analyze the literature data on the post-transplant course of allogeneic hematopoietic stem cell transplanted (alloHSCT) patients, which is affected by generated inflammatory cytokines. The sequence of events boosting cytokine production was analyzed in relation to clinical and laboratory data highlighting the impact of cytokine generation on the post-transplant course. The collected data were compared to those from studies on COVID-19 patients. The similarities are: (i) the damage/pathogen-associated molecular pattern (DAMP/PAMP) stage is similar except for the initiation hit being sterile in alloHSCT (toxic damage of conditioning regimen) and viral in COVID-19; (ii) genetic host-derived factors play a role; (iii) adaptive immunity fails, DAMP signal(s) increases, over-production of cytokines occurs; (iv) monocytes lacking HLADR expression emerge, being suppressor cells hampering adaptive immunity; (v) immune system homeostasis is broken, the patient’s status deteriorates to bed dependency, leading to hypo-oxygenation and malnutrition, which in turn stimulates the intracellular alert pathways with vigorous transcription of cytokine genes. All starts with the interaction between DAMPs with appropriate receptors, which leads to the production of pro-inflammatory cytokines, the inflammatory process spreads, tissue is damaged, DAMPs are released and a vicious cycle occurs. Attempts to modify intracellular signaling pathways in patients with post-alloHSCT graft vs host disease have already been undertaken. The similarities documented in this study show that this approach may also be used in COVID-19 patients for tuning signal transduction processes to interrupt the cycle that powers the cytokine overproduction.

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Prolonged activation of nasal immune cell populations and development of tissue-resident SARS-CoV-2 specific CD8 T cell responses following COVID-19

10.1101/2021.04.19.21255727 ◽

2021 ◽

Author(s):

Anna H.E. Roukens ◽

Marion König ◽

Tim Dalebout ◽

Tamar Tak ◽

Shohreh Azimi ◽

...

Keyword(s):

T Cells ◽

Immune System ◽

T Cell ◽

Nasal Mucosa ◽

Immune Cell ◽

Inflammatory Responses ◽

Upper Airway ◽

Effector Memory ◽

Long Term Effects ◽

Activated T Cells

AbstractThe immune system plays a major role in Coronavirus Disease 2019 (COVID-19) pathogenesis, viral clearance and protection against re-infection. Immune cell dynamics during COVID-19 have been extensively documented in peripheral blood, but remain elusive in the respiratory tract. We performed minimally-invasive nasal curettage and mass cytometry to characterize nasal immune cells of COVID-19 patients during and 5-6 weeks after hospitalization. Contrary to observations in blood, no general T cell depletion at the nasal mucosa could be detected. Instead, we observed increased numbers of nasal granulocytes, monocytes, CD11c+ NK cells and exhausted CD4+ T effector memory cells during acute COVID-19 compared to age-matched healthy controls. These pro-inflammatory responses were found associated with viral load, while neutrophils also negatively correlated with oxygen saturation levels. Cell numbers mostly normalized following convalescence, except for persisting CD127+ granulocytes and activated T cells, including CD38+ CD8+ tissue-resident memory T cells. Moreover, we identified SARS-CoV-2 specific CD8+ T cells in the nasal mucosa in convalescent patients. Thus, COVID-19 has both transient and long-term effects on the immune system in the upper airway.

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TLR, RAGE, and HMGB1 in the Inflammatory Response in Ph(-) Myeloproliferative Neoplasm

Blood ◽

10.1182/blood-2020-134988 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 31-32

Author(s):

Guanfang Shi ◽

Kiron Nair ◽

Preethi Ramachandran ◽

Chi Chen ◽

Ching Wong ◽

...

Keyword(s):

Inflammatory Response ◽

Real Time ◽

Inflammatory Cytokines ◽

Internal Control ◽

Real Time Pcr ◽

Mononuclear Cells ◽

Conflicts Of Interest ◽

Philadelphia Chromosome ◽

Myeloproliferative Neoplasm ◽

Significant Difference

Recent evidence of increased constitutional symptoms and inflammatory cytokines in Philadelphia chromosome negative (Ph (-)) MPN suggests that an inflammatory response is important in the pathogenesis of Ph (-) MPN. Toll-like receptors (TLR), Receptor for Advanced Glycation End products (RAGE) and High mobility group protein B1 (HMGB1) are the important pathways for the inflammatory response. All these three important pathway proteins were studied in MPN diseases in the current studies. Materials and Methods: TLR assay. TLR 2,3, 4, 7, 9 quantification was performed by immuno-staining of 1×106 mononuclear cells (peripheral blood) which were incubated with fluorescence-conjugated anti-TLR-2,3, 4, 7, 9 antibodies and assayed by flow cytometry. HMGB1assay:HMGB1 ELISA kit from Immuno-Biological Laboratories, Inc. (IBL-America) were used. The plasma samples were diluted four times with the provided sample dilution buffer, and assayed in duplicate according to the manufacturer's suggestion. RAGE (RT-PCR) Assay: Total RNA was extracted from normal control or patient mononuclear cells. Predesigned primers for RAGE, and internal control genes were ordered from Qiagen (Germantown, MD). Real-time PCR was performed using SsoAdvanced™ Universal SYBR® Green Supermix (Bio-Rad, Hercules, CA) on Bio-Rad iQ5 Multicolor Real-Time PCR Detection System. At least three house-keeping genes (ribosomal protein L4, TATA box binding protein, and tubulin-α 1b) were used as normalization controls. The expression of RAGE were compared with each internal control. Average of three was used to calculate the ratio of final patient to normal Results: Total of 97 patients with MPN were studied 1) TLR: TLR 3,7,9 was not significantly different from controls. But TLR 2 was significantly increased in both PV, as well as in the MPN group when PV, ET and MF were grouped together as MPN (Fig A). TLR 4 was not significantly increased in PV, ET, MF individually but was found to be significantly increased than the controls, when they are grouped together as MPN (Fig B). 2) RAGE: No significant difference was found between ET, PV, MF individually or when they were grouped together as MPN than the controls (Fig C). 3) HMGB1: No significant difference was seen between ET, PV, MF or when they were grouped as MPN (Fig D). Conclusion: Current study suggests that TLR pathway especially TLR2, and to a lesser extent TLR4 are the important pathways for inflammatory response with increased inflammatory cytokines in MPN, while HMGB1 and RAGE pathways were not different from controls. Figure Disclosures No relevant conflicts of interest to declare.

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Immunotropic effects in cultured human blood mononuclear cells exposed to a 900 MHz pulse-modulated microwave field

Journal of Radiation Research ◽

10.1093/jrr/rrz085 ◽

2019 ◽

Vol 61 (1) ◽

pp. 27-33

Author(s):

Łukasz Szymański ◽

Elżbieta Sobiczewska ◽

Aleksandra Cios ◽

Pawel Szymanski ◽

Martyna Ciepielak ◽

...

Keyword(s):

Immune System ◽

T Cell ◽

Mononuclear Cells ◽

Interleukin 2 ◽

T Cell Response ◽

Control Group ◽

Human Immune System ◽

Daily Lives ◽

Radiofrequency Radiation ◽

Set Up

ABSTRACT The specific biological effect of electromagnetic field (EMF) remains unknown even though devices present in our daily lives, such as smartphones and Wi-Fi antennae increase the environmental level of electromagnetic radiation. It is said that the human immune system is able to react to discrete environmental stimuli like EMF. To investigate the effect of 900 MHz microwave stimulation on the immune system our research aimed to analyze lymphocyte proliferation and observe and assess the basic immunoregulatory activities using a newly developed and improved anechoic chamber. Samples of mononuclear cells (PBMC) isolated from the blood of healthy donors were exposed to 900 MHz pulse-modulated radiofrequency radiation (20 V/m, SAR 0.024 W/kg) twice (15 min each) or left without irradiation (control group). Subsequently, the control and exposed cells were set up to determine several parameters characterizing T cell immunocompetence and monocyte immunogenic activity. Although the microcultures of PBMC exposed to radiofrequency radiation demonstrated higher immunogenic activity of monocytes (LM index) and T-cell response to concanavalin A than control cultures after first exposure, this parameter decreased after a second stimulation. Saturation of the interleukin-2 (IL-2) receptor rose significantly after the second day of exposure. On the other hand, response to mitogen dropped after EMF stimulation. The results suggest that PBMC are able to overcome stress caused by mitogens after stimulation with 900 MHz radiation.

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Maternal Supplementation of Food Ingredient (Prebiotic) or Food Contaminant (Mycotoxin) Influences Mucosal Immune System in Piglets

Nutrients ◽

10.3390/nu12072115 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2115

Author(s):

Stéphanie Ferret-Bernard ◽

Laurence Le Normand ◽

Véronique Romé ◽

Cindy Le Bourgot ◽

Julie Seeboth ◽

...

Keyword(s):

Immune System ◽

Lamina Propria ◽

Inflammatory Responses ◽

Intestinal Barrier ◽

Mucosal Immune System ◽

Food Ingredient ◽

Intestinal Immune System ◽

Maternal Supplementation ◽

Antigen Presenting ◽

The Impact

The early life period is crucial for the maturation of the intestinal barrier, its immune system, and a life-long beneficial host–microbiota interaction. The study aims to assess the impact of a beneficial dietary (short-chain fructooligosaccharides, scFOS) supplementation vs. a detrimental dietary environment (such as mycotoxin deoxynivalenol, DON) on offspring intestinal immune system developmental profiles. Sows were given scFOS-supplemented or DON-contaminated diets during the last 4 weeks of gestation, whereas force-feeding piglets with DON was performed during the first week of offspring life. Intestinal antigen-presenting cell (APC) subset frequency was analyzed by flow cytometry in the Peyer’s patches and in lamina propria and the responsiveness of intestinal explants to toll-like receptor (TLR) ligands was performed using ELISA and qRT-PCR from post-natal day (PND) 10 until PND90. Perinatal exposure with scFOS did not affect the ontogenesis of APC. While it early induced inflammatory responses in piglets, scFOS further promoted the T regulatory response after TLR activation. Sow and piglet DON contamination decreased CD16+ MHCII+ APC at PND10 in lamina propria associated with IFNγ inflammation and impairment of Treg response. Our study demonstrated that maternal prebiotic supplementation and mycotoxin contamination can modulate the mucosal immune system responsiveness of offspring through different pathways.

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Aloperine Protects Mice against DSS-Induced Colitis by PP2A-Mediated PI3K/Akt/mTOR Signaling Suppression

Mediators of Inflammation ◽

10.1155/2017/5706152 ◽

2017 ◽

Vol 2017 ◽

pp. 1-14 ◽

Cited By ~ 9

Author(s):

Xiaoxia Fu ◽

Fei Sun ◽

Faxi Wang ◽

Junai Zhang ◽

Biying Zheng ◽

...

Keyword(s):

T Cell ◽

Molecular Mechanisms ◽

Mononuclear Cells ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Activity Index ◽

Mtor Signaling ◽

Jurkat Cells ◽

Dependent Manner ◽

Activated T Cells

Colitis is a major form of inflammatory bowel disease which involved mucosal immune dysfunction. Aloperine is an alkaloid isolated from the shrub Sophora alopecuroides L. and has been recognized as an effective treatment for inflammatory and allergic diseases. The present study aimed to examine the molecular mechanisms underlying aloperine-mediated colitis protection. We found that aloperine treatment improved colitis induced by dextran sodium sulfate (DSS) based on body weight, disease activity index, colonic length, and spleen index. Aloperine also effectively attenuated DSS-induced intestinal inflammation based on the pathological score and myeloperoxidase expression and activity in colon tissues. In addition, aloperine regulated T-cell proportions and promoted Foxp3 expression in the spleens and mesenteric lymph nodes of DSS-induced colitis mice and in the spleens of the Foxp3GFP mice. Aloperine inhibited Jurkat and mouse naïve T-cell apoptosis. Furthermore, aloperine inhibited PI3K/Akt/mTOR signaling and upregulated PP2A expression in the DSS-induced colitis mice and in Jurkat cells, but LB-100 (PP2A inhibitor) resulted in an elevated Akt activity in Jurkat cells, activated T-cells, and human splenic mononuclear cells. Aloperine inhibited T-cell and lymphocyte proliferation, but LB-100 reverse these effects. In conclusion, aloperine regulates inflammatory responses in colitis by inhibiting the PI3K/Akt/mTOR signaling in a PP2A-dependent manner.

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The immune battlefield: The impact of inflammatory cytokines on CD8+ T-cell immunity

PLoS Pathogens ◽

10.1371/journal.ppat.1006618 ◽

2017 ◽

Vol 13 (10) ◽

pp. e1006618 ◽

Cited By ~ 11

Author(s):

Stephanie A. Condotta ◽

Martin J. Richer

Keyword(s):

T Cell ◽

Inflammatory Cytokines ◽

Cd8 T Cell ◽

T Cell Immunity ◽

Cell Immunity ◽

The Impact

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Use of Pre-Emptive Donor Lymphocyte Infusions To Achieve Durable Remission Following Alemtuzumab Based Reduced Intensity Conditioning (RIC) Transplantation for AML or MDS.

Blood ◽

10.1182/blood.v106.11.1124.1124 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1124-1124

Author(s):

ZiYi Lim ◽

Laurence Pearce ◽

Wendy Ingram ◽

Rafael Duarte ◽

Stephen Devereux ◽

...

Keyword(s):

T Cell ◽

Advanced Disease ◽

Disease Stage ◽

Mixed Chimerism ◽

Donor Chimerism ◽

Significant Difference ◽

Cell Source ◽

Recipient Age ◽

The Impact

Abstract Use of alemtuzumab in RIC HSCT reduces the incidence of graft rejection and graft vs host disease(GvHD). However, there can be a delay in full T-cell donor engraftment. As a dominant donor T-cell chimerism may be important to achieve a strong graft vs leukaemia effect(GvL), we examined the impact of pre-emptive DLI (pDLI) on patients with falling donor chimerism. 76 patients with AML or MDS were treated with RIC HSCT (fludarabine 150mg/m2, busulphan 8mg/kg, alemtuzumab 100mg). Complete sublineage chimerism data up to day +100 was available on all patients. The underlying diagnoses were AML n=27, MDS n=49. 33 patients had early disease vs 44 advanced disease (advanced disease as defined by AML >CR1, MDS RAEB or AML with multilineage dysplasia). The median recipient age was 51.6 years (range:19–72), with median follow-up of 526 days (range:137–1256). There were 30 sibling and 50 VUD allografts. Stem cell source was 61 PBSC vs 15 BM. 62 patients were fully HLA matched and 14 patients were HLA mismatched. CD15 engraftment occurred rapidly with 95% of patients achieving full donor chimerism(FDC) at day 30 and 96% at day 100. In contrast, CD3 engraftment was significantly delayed, with only 50% of patients FDC at day 30, 47% at day 100. Incremental doses of pDLI were considered for patients with falling donor chimerism (<50% donor) after day 100. Patients had immunosuppresion withdrawn, and had to have no GvHD. 20 patients received a total of 55 doses of pDLI. 10/20 had advanced disease, and 6/20 had unfavourable cytogenetics. Median donor CD3 chimerism at time of pDLI was 31.5%(range:7–59). The median CD3 dose of pDLI was 8.4x106/kg, with the first dose given at a median of day +176 (range:104–494). The median interval between pDLI was 8 weeks(range:4–22). 15 patients had FDC restored at median of 130 days following first doses of pDLI (range:36–523). 8/20 developed acute Gd II-IV GvHD following pDLI, with 2 patients dying of GvHD related complications. 2 patients relapsed with AML following treatment: with 1 death, and 1 patient currently undergoing treatment. 2 patients had not reached FDC at follow-up. A further 9 patients received DLI for cytogenetic or morphological relapse. Time to first dose of DLI was 257 days (range:76–837). The median CD3 dose was 1.67 x 107/kg. 3 patients were FDC and 6 patients MDC at time of relapse. All 3 patients with FDC failed to respond to DLI. Complete remission was seen in 3/6 patients with MDC. 4/9 patients developed acute Gd II-IV GvHD. 5/9 patients have died(all of underlying AML). The outcome of patients receiving pDLI was compared with patients with FDC(n=28), and stable mixed chimerism(defined as donor CD3 chimerism >70%) who did not receive DLI(n=18). There was no significant difference in recipient age, disease, disease stage, HLA type, cell source or cell dose between groups. However, there were more sibling donors in the group receiving pDLI(p=0.02). The 2 year DFS, OS and relapse rate was comparable between patients with FDC, stable chimerism and those receiving pDLI (59% vs 83% vs 67% p=0.22), (62% vs 88% vs 75% p=0.13), (12% vs 17% vs 15% p=0.74) respectively. In summary, pre-emptive DLI is effective in reversing falling donor chimerism, and can induce prolonged remission, even in a sub-group of patients with high risk disease. A dominant donor CD3 chimerism(>70%) may be sufficient to acheive an allo-immune effect in majority of patients.

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Lenalidomide IS Able to Restore Immune SYSTEM IN MULTIPLE MYELOMA PATIENTS.

Blood ◽

10.1182/blood.v114.22.4909.4909 ◽

2009 ◽

Vol 114 (22) ◽

pp. 4909-4909 ◽

Cited By ~ 3

Author(s):

Annalisa Chiarenza ◽

Nunziatina Parrinello ◽

Piera La Cava ◽

Eleonora Spina ◽

Daniele Tibullo ◽

...

Keyword(s):

Multiple Myeloma ◽

Immune System ◽

T Cell ◽

T Lymphocytes ◽

Mononuclear Cells ◽

Conflicts Of Interest ◽

Gradient Centrifugation ◽

Target Cells ◽

First Line ◽

Number Of Patients

Abstract Abstract 4909 LENALIDOMIDE IS ABLE TO RESTORE IMMUNE SYSTEM IN MULTIPLE MYELOMA PATIENTS Annalisa Chiarenza, Nunziatina Parrinello, Piera La Cava, Eleonora Spina, Daniele Tibullo, Cesarina Giallongo, Maide Cavalli, Alessandra Romano, Paolo Fiumara, Giuseppe A. Palumbo, Francesco Di Raimondo Background Multiple myeloma (MM) is a malignant plasma-cell proliferative disorder associated with dysfunctional T-cell responses. The immunomodulatory Thal derivative (IMiD) CC-5013 (lenalidomide) appears to be a promising agent for the treatment of myeloma. Although the exact antitumor mechanism of action of lenalidomide is unknown, a number of mechanisms are postulated to be responsible for it's activity (inhibition of angiogenesis, direct antiproliferative and proapoptotic effects on MM cells, suppression of pro-inflammatory cytokines, modulation of myeloma-stromal cells adhesive interactions). In addition, it has been demonstrated that lenalidomide in vitro is able to enhance T cell proliferation and to promotes ADCC. In this study we evaluated if MM patients have a deficit of T-reg (CD4+, CD25+, and FOXP3+) and of T lymphocytes bearing CD200 (a tolerogenic molecule) and the effect of lenalidomide treatment on these parameters. In addition, we investigated whether lenalidomide could improve ex vivo the ADCC against myeloma cells. Materials and methods Eight patients with previously untreated MM (median age 56 years) were treated with lenalidomide plus dexamethasone as first line therapy. Lenalidomide was given orally 25 mg daily on days 1 to 21 of a 28-day cycle. Dexamethasone was given orally 40 mg daily on days 1, 8, 15, 22 of each cycle. All patients were evaluable for response and toxicity. Peripheral blood mononuclear cells (PBMNc) were obtained from MM patients using density gradient centrifugation (Fycoll) under sterile condictions, at the beginning of treatment and after 4 cycles of therapy. The percentage of T-reg (CD4+CD25+FOXP3+) and the expression of CD200 on T- lymphocytes were evaluated by cytometry. Twelve healthy subjects were used as control. Moreover, PBMNc (effector cells, E) were incubated with MM cells line ARH-77 (target cells, T), previously labelled with CFDA,SE (carboxyfluorescein diacetate, succinimidyl ester) as a tracing fluorescent marker, in culture medium (RPMI-1640, 10%FCS, 1%penicillin/streptomycin) at different concentration (T/E ratio 1:20, 1:40). After 18-24 h co-colture cells were analyzed by flow cytometry and MM plasma cells cytotoxicity was calculated as the percentage of positive CFDA,SE/propidium cells. Myeloma cell viability was determined by tripan blue esclusion and apoptosis was also evaluated using Annexin V/propidium assay. Two MM patients treated in first line with a combination of Velcade, Thalidomide and Dexamethasone (VTD) were used as control and the experiments were performed in duplicate. Results MM patients have a significantly lower rate of CD4+/CD25+/FOXP3+ and CD200+/CD3+ than normal (28,3±14,9/mmc and 37,8±24,7 /mmc vs 79,3±27,8 and 79,5± 48,9)(p=0,0001 and p=0,01 respectively). In our study, lenalidomide treatment resulted in an increase both of Treg cells and T-lymphocytes espressing CD200. This improvement is not statistically significant probably due to the low number of patients examined (tab I). More important, we observed that PBMC derived from patients treated with lenalidomide showed an increase ability to kill a target MM cell line compared to PBMC collected at diagnosis (CFDA,SE/propidium cells 11% vs 68%). This effect was more prominent in patients treated with lenalidomide than in MM patients treated with VTD (CFDA,SE/propidium cells 12% vs 39%), Fig.1. Conclusions Our data emphasize the role of lenalidomide in modulating the endogenous tumor-specific immune response and underline the anti-myeloma activity of these new class of drugs. Disclosures No relevant conflicts of interest to declare.

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VISTA: A Target to Manage the Innate Cytokine Storm

Frontiers in Immunology ◽

10.3389/fimmu.2020.595950 ◽

2021 ◽

Vol 11 ◽

Cited By ~ 1

Author(s):

Mohamed A. ElTanbouly ◽

Yanding Zhao ◽

Evelien Schaafsma ◽

Christopher M. Burns ◽

Rodwell Mabaera ◽

...

Keyword(s):

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Cell Function ◽

Inflammatory Responses ◽

Constitutive Expression ◽

Immune Checkpoints ◽

Complete Suppression ◽

Wide Range ◽

The Impact

In recent years, the success of immunotherapy targeting immunoregulatory receptors (immune checkpoints) in cancer have generated enthusiastic support to target these receptors in a wide range of other immune related diseases. While the overwhelming focus has been on blockade of these inhibitory pathways to augment immunity, agonistic triggering via these receptors offers the promise of dampening pathogenic inflammatory responses. V-domain Ig suppressor of T cell activation (VISTA) has emerged as an immunoregulatory receptor with constitutive expression on both the T cell and myeloid compartments, and whose agonistic targeting has proven a unique avenue relative to other checkpoint pathways to suppress pathologies mediated by the innate arm of the immune system. VISTA agonistic targeting profoundly changes the phenotype of human monocytes towards an anti-inflammatory cell state, as highlighted by striking suppression of the canonical markers CD14 and Fcγr3a (CD16), and the almost complete suppression of both the interferon I (IFN-I) and antigen presentation pathways. The insights from these very recent studies highlight the impact of VISTA agonistic targeting of myeloid cells, and its potential therapeutic implications in the settings of hyperinflammatory responses such as cytokine storms, driven by dysregulated immune responses to viral infections (with a focus on COVID-19) and autoimmune diseases. Collectively, these findings suggest that the VISTA pathway plays a conserved, non-redundant role in myeloid cell function.

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