bluuebunny/crossref_metadata_2025 huggingface dataset:
IL-22 reduces the mortality of type 2 diabetes mellitus (T2DM) mice infected with Mycobacterium tuberculosis
Authors: Tripathi Deepak , Radhakrishnan Rajesh Kumar , Thandi Ramya Sivangala , Paidipally Padmaja , Devalraju Kamakshi Prudhula , Neela Venkata Sanjeev Kumar , Tvinnereim Amy R. , Valluri Vijaya Lakshmi , Vankayalapati Ramakrishna
Published: January 2023

IL-22 play an important role in protective immune responses against bacterial infections including Mtb and maintains homeostasis by regulating excess inflammation. IL-22 can also regulate glucose homeostasis, suggesting IL-22 pathway as a novel target for therapeutic intervention. Previously, we developed a mouse model of type 2 diabetes mellitus (T2DM) and found that pathological immune response enhances mortality of Mycobacterium tuberculosis (Mtb) infected T2DM mice. In the current study, we determined the role of IL-22 during Mtb infection in T2DM mice. We found innate lymphoid 3 cells (ILC3) are the major source for IL-22 and IL- 22 production was significantly reduced in the lungs and serum of T2DM mice infected with Mtb. Recombinant IL- 22 or adoptive transfer of ILC3 cells prolonged the survival of Mtb infected T2DM mice. Recombinant IL-22 prevented neutrophil accumulation near alveoli, reduced the serum insulin level and improved the lipid metabolism. Recombinant IL-22 also prevented neutrophil-mediated epithelial cell damage by inhibiting elastase production by neutrophils. Further, we found serum IL-22 levels were significantly less in tuberculosis (TB) patients with T2DM compared to TB patients without T2DM. Our findings suggest that IL-22 produced by ILC3 cells is essential to inhibit excess inflammation, epithelial cell damage in T2DM mice infected with Mtb.
IL-17D promotes anti-bacterial immunity in Group A Streptococcus infection
Authors: Washington Allen , Valderrama Andres , Nizet Victor , Varki Nissi , Bui Jack D
Published: January 2023

Interleukin (IL)-17D is a cytokine in the IL-17 family that is conserved in vertebrates and invertebrates. In contrast to IL-17A, which is expressed in T cells, IL-17D is expressed broadly in non-immune cells. IL-17D can promote immune responses to cancer and viruses in part by inducing chemokines that recruit natural killer cells and neutrophils. Although bacterial infection can induce IL-17D in other species, the role of mammalian IL-17D in anti-bacterial immunity has not been determined. In order to ascertain whether IL-17D has a role in mediating immunity against bacterial infections, we studied intraperitoneal infection by Group A Streptococcus (GAS) S. pyogenes in wild-type (WT) and IL-17D-deficient mice. We found that there was more weight loss and decreased survival in mice deficient in IL-17D compared to WT animals after GAS infection. In addition, IL-17D deficient animals had increased bacterial burden in the kidney and peritoneal cavity after GAS infection compared to WT animals. In WT animals, IL-17D transcript could be induced by GAS infection, correlating with increased levels of the chemokine CCL2 and neutrophil recruitment. Notably, GAS-mediated induction of IL-17D seemed to require live bacteria, indicating that pattern recognition did not mediate induction of IL-17D. Altogether, our results demonstrate a role for IL-17D in sensing replicating bacteria and inducing immune responses important in clearing bacteria in distant organs.
A directly GP130-targeting small molecule ameliorates collagen-induced arthrites by inhibiting IL-6/GP130 signalling and Th17 differentiation
Authors: Kim Hee Jung , Park Yeon-Hwa , Heo Tae-Hwe
Published: January 2023

Rheumatoid arthritis is a chronic inflammatory disease that is characterized by joint destruction and inflammation by T helper 17 (Th17) cells. Interleukin-6 (IL-6) is secreted in cells such as macrophage or synovial fibroblast and induces the differentiation and function of Th17 cells that increase lymphocytic infiltration in the joint. LMT-28 suppresses IL-6 signaling through direct binding to glycoprotein-130, and alleviates inflammatory disease (such as rheumatoid arthritis, inflammatory bowel disease) in previous study. The purpose of this study is to assess whether LMT-28 would potently inhibit Th17 differentiation, and the mechanism of LMT-28 that attenuates rheumatoid arthritis through IL-6 signaling pathway. LMT-28 reduced the arthritis score and showed protective effects against bone and cartilage destruction in collagen induced arthritis (CIA) mice. In mice with CIA, LMT-28 markedly decreased the serum levels of IL-6, TNF, and IL-1β compared with each vehicle treated group. Moreover, LMT-28 attenuated Th17 cell activation in lymph nodes of CIA mice. We demonstrated that LMT-28 suppressed differentiation of Th17 in mouse splenocytes and human PBMCs. Additionally, LMT-28 inhibited the phosphorylation of GP130, STAT3, and ERK induced by Hyper IL-6 in human fibroblast-like synoviocytes(FLS). Collectively, these results suggested that LMT-28 inhibits differentiated/activated-Th17 cells in rheumatoid arthritis by blocking activation of the STAT3 pathway.
An autoimmune disease risk SNP, rs2281808, in SIRPG is associated with reduced expression of SIRPγ and heightened effector state in human CD8 T-cells
Authors: Sinha Sushmita
Published: January 2023

Multiple GWAS studies have shown that the SNP rs2281808 TT variant, present within the SIRPG gene, is associated with autoimmune diseases, such as type 1 diabetes. However, the role of SIRPγ in human T-cells is not known, neither is the functional significance of TT variant. Here we investigated SIRPG genotypes and their effects on the fate and function of human T-cells. We found that the presence of T variant resulted in reduction of SIRPγ expression on T-cells. Functionally, SIRPγlow CD8 T-cells in CT and TT individuals existed in a heightened effector state with lower activation threshold and had greater expression of genes and molecules associated with migratory and cytotoxic potential. Further, SIRPγlow CD8 T-cells were deficient in transcription factors associated with long-term functional memory formation. Our study reveals biological consequences of the SNP rs2281808 and provides novel insights into the potential mechanisms by which SIRPγ might regulate human immune responses.
Reduced gravity contributes to Neutrophil to Lymphocyte Ratio shifting and promotion of the Oxidative Stress Response
Authors: Paul Amber M , Mhatre Siddhita D. , Cekanaviciute Egle , Schreurs Ann-Sofie , Tahimic Candice G.T. , Globus Ruth K , Crucian Brian , Bhattacharya Sharmila
Published: January 2023

Spaceflight can cause immune system dysfunction, such as elevated white blood cells (WBC) and polymorphonuclear neutrophils (PMN), along with unchanged or reduced lymphocyte counts. A high PMN to lymphocyte ratio (NLR) can acts as a poor prognosis in cancer and a biomarker for subclinical inflammation however, the NLR has not been identified as a predictor of astronaut health during spaceflight. CBC data collected on board the International Space Station (ISS) was repurposed to determine the granulocyte to lymphocyte ratio (GLR) in humans and the NLR in rodents. The results displayed a progressive increase in GLR and NLR during spaceflight and at landing. The mechanism for increased NLR was assessed in vitro using the microgravity-analog, rotating wall vessel (RWV), with human WBCs. The results indicated that simulated microgravity led to increased GLR and NLR profiles, and production of reactive oxygen species (ROS) and myeloperoxidase (MPO). Interestingly, simulated microgravity increased the number of matured PMNs that showed impaired phagocytic function, while treatment with tert-Butyl hydroperoxide (TBHP), also reduced PMN phagocytosis. In addition, 30-days of simulated microgravity (hindlimb unloading) in mice, indicated an increased NLR and MPO gene expression, which were mitigated in mitochondrial catalase overexpressing transgenic mice, suggesting ROS scavenging is essential for maintaining homeostatic immunity. Collectively, we propose that the health status of astronauts during future short- and long-term space missions can be monitored by their NLR profile, in addition to utilizing this measurement as a tool for oxidative stress response countermeasure development to restore homeostatic immunity.
Identification of T-cell subsets associated with muscle strength in people with cancer: A pilot study
Authors: Narsale Aditi , Moya Rosa , Ma Jasmin , Anderson Lindsey , Wu Daniel , Garcia Jose , Davies Joanna D
Published: January 2023

Background

Immune deficiency and muscle wasting are both associated with poor prognosis in people with cancer. Survival and quality of life can be improved by attenuating either the immune response or muscle mass, suggesting a relationship between them. Previous data show that mice injected with precursor CD4 T cells maintain muscle mass by restoring immune homeostasis. These data are consistent with the hypothesis that robust anti-cancer T cell immunity leads to improved muscle health. As a first step, this study aims to determine if circulating T cell subsets correlate with muscle strength in people with cancer.

Methods

The frequency(freq) of T cell subsets was quantified in 11 men with gastrointestinal cancer, and 9 men without cancer, using flow cytometry. Total PBMC protein and gene expression was analyzed using qPCR and Western blots. Clinical measures were assessed using: DEXA scan (body composition); Hand-grip (HGS) test and Knee extension test (Muscle Strength); Stair Climb test (Performance) and Karnofsky and ECOG scales (functional impairment). Data was analyzed using Spearman’s correlation and ANOVA.

Results

Our data show significant correlations between i) higher freq of CD8 naïve and EM T cells, and lower freq of CD8 CM T cells with stronger HGS, ii) lower freq of Tregs with greater lean mass index, iii) lower freq of CD8 cells expressing CD95 with greater Stair Climb Power, iv) higher freq of CD197+CD45RA+ T cells and greater knee extension strength, and iv) higher expression of CD4 in whole blood with greater functional impairment in people with cancer.

Conclusions

We have identified significant correlations between levels of T cell populations and muscle strength, performance, and body composition in people with cancer.
Increased expression of CD40 and CD40L in acute coronary syndrome patients: association with genetic variants in western Mexican population
Authors: Martinez-Fernandez Diana Emilia , Padilla-Gutiérrez Jorge Ramón , Casillas-Muñoz Fidel , Valdés-Alvarado Emmanuel , Parra-Reyna Brenda , Aceves-Ramírez Maricela , Muñoz-Valle José Francisco , Valle-Delgadillo Yeminia
Published: January 2023

Acute coronary syndrome (ACS) belongs to the clinical entities characterized by obstruction of a coronary artery. In its etiology, inflammation contributes significantly trough the activation of immune cells by co-stimulatory molecules as CD40 and CD40L. The purpose of this work was to explore the changes of mRNA and circulating soluble levels of CD40-CD40L in ACS patients and association with genetic variants in a western Mexican population.

320 ACS patients and 300 individuals with similar age than cases without ischemic cardiopathy were recruited. Genotype determination was made using TaqMan SNP genotyping assays. CD40 and CD40L mRNA expression in whole blood samples were quantified using TaqMan Gene Expression Assays. Soluble levels were measured in plasma by enzyme-linked immunosorbent assay.

We did not find evidence of association between on CD40 (rs1883832, rs4810485 and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS nor changes in their mRNA expression (p>0.05), although rs1883832 and rs4810485 affected significantly sCD40 circulating levels (p=0.005; p=0.015, respectively). Circulating soluble levels were higher in ACS patients; specifically sCD40L was higher in male patients with unstable angina compared to female patients (p=0.016).

Our results showed genetic variants affect soluble levels of CD40 although the CD40 and CD40L polymorphisms are not associated with susceptibility to ACS in western Mexican population. CD40L mRNA expression, sCD40 and sCD40L plasma levels were higher in ACS patients even when they are under pharmacological treatment, which suggests an active role of the CD40-CD40L system in the immunopathogenesis of acute coronary syndrome.
The Th2 cytokine IL-4 mediates loss of skin γδT cells in atopic dermatitis
Authors: Wang Jocelyn , Fu Yongyao , Kaplan Mark H
Published: January 2023

Atopic dermatitis (AD) is a common Th2-biased chronic inflammatory skin disease. Major clinical manifestations include erythema, severe itchiness, and dry skin that impose a burden on patients and impairs their quality of life. Extensive research has been conducted to identify possible underlying mechanisms and develop therapeutic approaches. γδT cells, an understudied T cell population, play important roles in maintaining skin integrity in both human and mice. They are among the first responders to epithelial wounding and are a source of keratinocyte/fibroblast growth factors that promote wound repair. Hence, we wanted to investigate their behavior during wounding in an AD-like environment. Using a mouse model, we observed that γδT cell numbers are drastically decreased in atopic skin. Multiple factors contribute to this decrease, including insufficient activation, less proliferative capacity and increased cell death. These changes in γδT cell function are IL-4 dependent. Administration of IL-4 to wild type (WT) mice resulted in significant loss of γδT cells, and Il4−/− mice in the AD model showed numbers of γδT cells similar to WT controls. We further observed that the levels of keratinocyte/fibroblast growth factors are lower in AD animals, suggesting that loss of γδT cells could compromise re-epithelialization and repair following wounding. Collectively, our data indicate that in an atopic environment, γδT cells decrease drastically in an IL-4 dependent fashion, which may contribute to the aberrant wound healing process in AD animals.
Nerve growth factor receptor expression marks activated human perivascular adventitial fibroblasts in distinct perturbed states
Authors: Barron Alexander Michael Shuford , Ho Jonathan Dale , Mantero Julio C. , Bhawan Jag , Browning Jeffrey L
Published: January 2023

Vascular alterations are common in human autoimmune skin diseases, including systemic sclerosis and discoid lupus. Much is known about endothelial cell, pericyte and vascular smooth muscle cell activation. In contrast, the adventitial layer of the vascular unit is less well explored. This compartment serves as a reservoir for leukocytes and mesenchymal stem cells, and appears to play important sentinel and remodeling roles. We recently demonstrated that the compartment, as well as the perivascular adventitial fibroblasts, expand in the skin of systemic sclerosis, discoid lupus, and dermatitis patients. Vascular cell adhesion molecule-1 (VCAM) display marked activated adventitial fibroblasts in discoid lupus and dermatitis, and correlated with perivascular T cell infiltration. Here we demonstrate elevated expression of Nerve growth factor receptor (NGFR) by perivascular adventitial fibroblasts in the skin of systemic sclerosis patients but not control subjects. Adventitial NGFR expression occurred without elevated VCAM indicating a distinct activation state. Conversion to the NGFR+ state was also observed in the absence of large, perivascular leukocyte infiltrates. In systemic sclerosis, NGFR was more common than VCAM on perivascular adventitial fibroblasts. Conversely, in discoid lupus lesions, VCAM was more common than NGFR on adventitial fibroblasts suggesting two distinct activation programs. Similar adventitial NGFR staining was seen in both pathological (e.g. hypertrophic and keloid) and normal reparative skin wounds. Our data indicate that elevated NGFR expression can identify an activated perivascular adventitial fibroblast in disease.
Kinetics of immune cell responses in the multiple low dose streptozotocin mouse model of type 1 diabetes
Authors: Luo Zhengkang , Soläng Charlotte , Blixt Martin , Carlsson Per-Ola , Sandler Stellan , Singh Kailash
Published: January 2023

In type 1 diabetes (T1D), the insulin producing β cells are damaged by immune attacks. It has been hypothesized that the very first response in T1D onset comes from innate immune cells, which further activates the adaptive immune cells to attack the β cells. The kinetics of the infiltration of different immune cells in the multiple low dose streptozotocin (MLDSTZ) induced T1D mouse model is still unclear. Therefore, we used flow cytometry to investigate the proportions of innate immune cells such as neutrophils, dendritic cells (DCs), plasmacytoid DCs (pDCs) and macrophages, and adaptive immune cells (T and B lymphocytes) in thymi, pancreatic draining lymph nodes (PDLNs) and spleens of MLDSTZ mice on days 3, 7, 10 and 21 after the first injection of MLDSTZ. The proportions of DCs and pDCs were increased on day 3 while the proportions of B-1a lymphocytes and neutrophils were increased on day 10 in MLDSTZ treated mice, illustrating that the initial immune response is induced by DCs and pDCs. The proportions of T helper 1, Helios+ T cells and cytotoxic T cells were increased from day 7, suggesting that the innate immune cells precede the adaptive immune cell response in MLDSTZ mice. We also found the proportions of interleukin-35 (IL-35) expressing tolerogenic antigen presenting cells (tolAPCs) were decreased in the spleens of MLDSTZ mice than in control mice on day 21. Furthermore, we found the proportions of IL-35+ tolAPCs were decreased in the peripheral blood mononuclear cells from T1D patients than from healthy controls. Altogether, our data demonstrate a possible sequence of events regarding the involvement of DCs, pDCs, B-1a lymphocytes, neutrophils, and Helios+ T-cells at the early stage of T1D development.
Biochemical and Functional Characterization of the ICOSL TNFR2 Interaction
Authors: Herrera Natalia Guadalupe , Garrett-Thomson Sarah , Almo Steven
Published: January 2023

To evade the immune response, cancers hijack the anti-inflammatory function of T regulatory Cells (Tregs) through blockade of anti-tumor responses carried out by T cells (effector and cytotoxic). Tumor necrosis factor receptor 2 (TNFR2) positive Tregs are highly immunosuppressive and enriched in the tumor microenvironment. Thus, immunotherapies targeting TNFR2 with antagonistic or agonistic antibodies are promising therapeutics for decreasing or increasing Treg cell levels, respectively. TNFR2 is activated by engagement with the cytokine, TNF alpha (TNFa), which leads to cell survival and proliferation through activation of the NFkB pathway, and this is extensively studied in terms of Treg cell proliferation and survival. Using a high-throughput cell-cell based screening approach, the Almo lab identified ICOS ligand (ICOSL) as a novel interacting partner of TNFR2. ICOSL is a costimulatory molecule with wide tissue distribution and with the ability to bind type-I transmembrane proteins CD28, CTLA-4 and ICOSR. ICOSL interactions with these receptors have been implicated in both positive and negative regulation of T cell activity. While TNFa binding to TNFR2 can activate NFkB signaling, it is unclear if ICOSL binding serves a blocking or activating function. We hypothesize the ICOSL-TNFR2 interaction functions as an additional mechanism for activating/stimulating TNFR2+ Treg cells through processes such as survival, cytokine production and expansion.
IL-15-driven clonal expansion of TLR9-primed human B-CLL is characterized by activation of AKT and STAT5, downstream elevation of cyclin D2 and repression of DNA damage response mediators, ATM and TP53BP
Authors: Mongini Patricia K A , Gupta Rashmi , Allen Steven L , Barrientos Jacqueline , Kolitz Jonathan E , Rai Kanti , Chiorazzi Nicholas
Published: January 2023

Clonal expansion of B cell chronic lymphocytic leukemia (B-CLL) is linked to mutagenesis and occurs within lymphoid tissues. CpG DNA (ODN-2006) and IL-15, a cytokine found within stromal cells of B-CLL-infiltrated tissues, manifest striking synergy in promoting in vitro growth of B-CLL cells (J Immunol 195:901–923, 2015). Synergy is in part explained by an ODN-induced, NF-kB (p65)-dependent elevation of IL-15Rα and IL-2/15Rβ (CD122) mRNA and protein (J Immunol 201:1570–1585, 2018). Most recently, we examined the downstream consequences of IL-15 signaling through experiments involving intracellular immunofluorescence staining, pharmacologic inhibitors, RT-PCR, and western blotting. Levels of activated pAKTSer473 and pSTAT5Tyr694 were significantly elevated soon after IL-15 exposure to ODN-primed B-CLL cells; furthermore, STAT5 remained activated throughout cycling. Pharmacologic inhibitors of PI-3K or STAT5 blocked IL-15-driven growth, indicating the functional relevance of these pathways. RT-PCR experiments +/− these inhibitors show that IL-15 signaling in B-CLL is characterized by PI-3K & STAT5-dependent rise in cyclin-D2 and repression of two important DNA damage response (DDR) mediators, ATM and TP53BP1, known to dampen growth and facilitate DNA repair. Repression of the latter two proteins was confirmed by western blotting and immunofluorescence studies. We conclude that IL-15 signaling in TLR9-primed B-CLL can provoke a rapid burst in growth via mechanisms resembling those recently described in CD8 T cells. Nonetheless, because dividing B-CLL cells additionally upregulate the mutagenic enzyme, AICDA (Blood 120: 4802–4811, 2012), these simultaneous events may augment B-CLL mutagenesis.
Symphony of Life: Genetics, Immunology, Cancer & Aging I. Genetic and immunological evaluation of mice with histocompatible tumors, virus induced breast cancer and survivors of metastatic breast cancer, HIV infection, and old people
Authors: Williams R Michael , Zuniga Joaquin , Williams R Michael , Granados Julio , Feris Edmond Tato , Yunis Edmond J.
Published: January 2023

Antigen altered idiotype induces immune suppression through the production of a "hole" in the antigenic/epitope specificity repertoire, the consequences of which can be a acquired immune deficiency SYNDROME called AIDS. There are measurable immunological consequences which include decreased CD4 cell numbers and low CD4/CD8 ratios and uncommon DISEASES like pneumocystis carinii pneumonia, virus induced cancers such as CMV mediated Kaposi's sarcoma or HPV mediated cancers (Kaposi's sarcoma, cervical cancer, tonsil cancer, etc.) and other DISEASES for which no viral etiology has been proven (breast cancer, lung cancer, melanoma, anal cancer, colorectal cancer, etc.). When there is the double whammy of immune deficiency AND virus infection, particularly one which preferentially infects and/or kills a distinct cell population (CD4+ lymphocytes in man, MTV induced mammary cancer in mice) the disease such as AIDS/HIV or metastatic breast cancer, are particularly severe. The measurable components of the immune system (CD4 counts, CD4/CD8 ratios, Tregs, CTLs, quantitative immunoglobulins, NK cell numbers and NK cell activity and cytokine levels are altered. We will present data including genetic (MHC class I, NK cell receptor ligands) and immunological (cell numbers in old mice or humans, metastatic breast cancer or HIV infected people, and those who are older than 90. Populations tested include centenarians Mexico City, mice surviving after a Sendai virus epidemic or injection of a histocompatible tumor, active homosexuals, and long term survivors of breast cancer or HIV infection. Data include MHC class I allele interaction with NKG2A receptors in Mexicans, survivors of breast cancer and long term non progressors with HIV infection.
Pulmonary Eosinophilic Granulomatosis with Polyangiitis (EGPA) has Allergic and Immunoregulatory Features
Authors: Lin Edwin , Dong Zack , Wechsler Michael , Yandell Mark , Clayton Frederic
Published: January 2023

Introduction

Eosinophilic granulomatosis with polyangiitis (EGPA) is a life-threatening vasculitis that can cause heart failure, neuropathy, and organ damage. EGPA is a rare cause of systemic vasculitis, and its prevalence is estimated at 1 in 2 million. The pathophysiology of EGPA is poorly understood. We aim to characterize EGPA lung immunopathologic findings.

Methods

We studied five open lung biopsies and one transbronchial biopsy of active, untreated EGPA patients and compared them to lung tissue controls. They were studied by histopathology, immunostaining, and RNA sequencing with confirmatory RT-PCR.

Results

The characteristic parenchymal interstitial infiltrate contains eosinophils, FoxP3+ regulatory T cells (Tregs), abundant macrophages, basophils, mast cells, and many IgG4 plasma cells. IgG4+ granular deposits resembling immune complexes are present focally, some coating macrophages. RNA studies confirm that EGPA lung has abundant IGHG4 (increased 1,885-fold relative to controls, p<2E-15) and, to a lesser degree, other immunoglobulin transcripts. Statistically significant increases, each ≥8-fold greater in EGPA compared to controls, are also seen for SIGLEC8 (for eosinophils), FOXP3, IL13, CCL18, CCL13, B cell markers, CYP27B1 (which makes calcitriol, active vitamin D) and the alternatively activated macrophage marker CD209 (DC-SIGN).

Conclusions

EGPA has both type 2 and immunoregulatory features. We propose a novel mechanism involving these findings that induces the EGPA immune response.
A phase 1, randomized, controlled clinical study of CC-11050 in people living with HIV with suppressed plasma viremia on antiretroviral therapy (APHRODITE)
Authors: Boulougoura Afroditi , Gabriel Erin , Laidlaw Elizabeth , Khetani Vikram , Arakawa Ken , Higgins Jeanette , Rupert Adam , Gorelick Robert J. , Lumbard Keith , Pau Alice , Poole April , Kibiy Angela , Kumar Princy , Sereti Irini
Published: January 2023

Background

Phosphodiesterase 4 inhibitors (PDE4i) block the degradation of cyclic adenosine monophosphate and modulate both innate and adaptive immune responses. PDE4i have been approved for rheumatologic diseases and tested as host-directed therapy in TB. We examined the safety of CC-11050, a new potent PDE4i, in HIV+ people with suppressed viral load (VL). We hypothesized that CC-11050 could be used to modulate HIV-related inflammatory responses.

Methods

Thirty HIV+ participants, on antiretroviral therapy (ART) ≥ 1 year with HIV VL <50 copies/mL were randomized 2:1 to 12 weeks of CC-11050 200mg BID or placebo with follow-up at weeks 2, 4, 8, 12 and 16. Primary endpoint was safety. We also assessed the effect of CC-11050 on CD4+, CD8+, NK, VL, plasma cytokines, monocyte and T-cell activation.

Results

At baseline, median age was 49.5 years and CD4+ 459 cells/μL. Most frequent adverse events (only grades 1–2) in CC-11050 group were headache, diarrhea, nausea, cough and nasal congestion. The CC-11050 group had lower IL-8 level after adjustment for baseline level, group and week (0.72 fold, p=0.02) and lower %NK cells compared to placebo (0.87 fold, p=0.02). At week 12, the CC-11050 group had higher %CD14++CD16+ monocytes than placebo (median 58.5% vs 50.7%, p=0.03). There was no significant effect on plasma HIV viremia, assessed by single copy assay and on cell-associated DNA and RNA in PBMC.

Conclusions

CC-11050 was well tolerated in HIV+ participants without affecting controlled viremia. CC-11050 had an effect on innate immune mechanisms, by decreasing NK cells and IL-8 level and increasing intermediate monocytes. Further study is needed to elucidate the efficacy of CC-11050 as potential anti-inflammatory adjuvant strategy in HIV.
TGF-beta in the UCB-MSCs inhibit TNF-alpha in human mast cells and atopic dermatitis
Authors: Park HwanHee , Yu Yeon-sil , Baek Song-Yi , Yoo Sae-Mi , Seo Kwang-Won , Kang Kyung-Sun
Published: January 2023

It is well known that umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) have been effective therapy in autoimmune inflammatory disease such as atopic dermatitis (AD), rheumatoid arthritis (RA) and psoriasis. Especially, UCB-MSC has a prominent therapeutic effect on AD. However, there is not much research on the mechanism of alleviation of AD by UCB-MSCs. In this study, we investigated the mechanism of AD therapy by UCB-MSCs, using human mast cells as the major pathogenic cells in AD. LAD2 cells were stimulated with IL- 33(30ng/ml) and Ionomycin (1uM) under IgE-XL condition and they secreted a significant amount of TNF-a. TNFa was significantly inhibited by co-culture with UCB-MSCs. UCB-MSCs secreted TGF-beta and PGE2, which play a crucial role in immune regulation. TNF-a of LAD2 was increased when co-cultured with UCB-MSCs after TGF-b siRNA transfection. Nevertheless, inhibition of PGE2 using indomethacin, NS398 and celecoxib did not restore secretion of TNF-a. At the protein level, we examined the ERK, JNK and AKT signaling pathways involved in TNF-α, and only the ERK signaling pathway was associated with TNF-α inhibition. Finally, we found that TNFa is regulated by TGFb induced by UCB-MSC in a DF-induced mouse model. Taken together, our findings suggest that TGF-b may play an important role in regulating mast cells in AD rather than PGE2 in UCB-MSCs.
Upregulation of endocannabinoids in fatty acid amide hydrolase (FAAH) knockout mice prevents staphylococcal enterotoxin B (SEB)-mediated acute lung injury through changes in the microbiome, immune and metabolic profiles
Authors: Sultan Muthanna Ali , Nagarkatti Prakash , Nagarkatti Mitzi
Published: January 2023

Endogenous cannabinoids are considered key regulators of biological systems as they have been shown to exhibit anti-inflammatory properties, while the fatty acid amide hydrolase (FAAH) enzyme plays a role in degrading the endogenous cannabinoid, anandamide. Staphylococcus Enterotoxin B (SEB) is a superantigen that can cause acute lung injury (ALI) through inhalation. In this study, we found that FAAH knockout mice (FAAH−/−) were more resistant to developing SEB-induced ALI 48 hours after intranasal administration of 50 μg dose of SEB compared to wildtype (WT) mice. The SEB-treated FAAH −/− mice had similar clinical parameters and upregulation of endogenous anandamide as naïve FAAH−/− mice. The results from assessing the clinical profile by plethysmography showed unlike with WT groups, there were no significant changes in the functions of the lung in FAAH−/− exposed to SEB when compared to naive FAAH−/−. Immune profiling by flow cytometry revealed there were also no changes in T cells subsets or cytokine levels among naive or SEB-treated FAAH−/− mice. Furthermore, after MiSeq sequencing V3-V4 region of the 16S rRNA of colon/cecal flush and lung samples, both the bacterial phylogenetic and short chain fatty acid (SCFA) profiles showed no significant differences in naïve FAAH−/− mice compared to those treated with SEB, unlike WT groups that had significant differences in these profiles. Lastly, further investigation of the metabolic profile by glycolysis rate assay (GRA) of splenocytes from both experimental groups showed no significant differences in this metabolic pathway. Collectively, these data suggest that knockdown of the FAAH enzyme may lead to increase endogenous cannabinoid, anandamide, thereby preventing SEB-induced ALI.
Single-Step Purification of Sputum Extracellular vesicles from Cystic Fibrosis patients using aF4-MALS
Authors: Dobosh Brian , Liu Susan , Chen Michelle , Tirouvanziam Rabindra M
Published: January 2023

Rationale

Patients with cystic fibrosis (CF) present a large amount of respiratory damage caused in large part by chronic neutrophil influx into the lung. Neutrophils recruited to the lumen of the CF lung actively exocytose neutrophil elastase (NE) and other damaging molecules. Airway NE levels correlate strongly with disease severity in patients with CF. We previously showed that extracellular vesicles (EVs) from patients with other lung diseases carry NE and promote emphysema in a mouse model (Genschmer et al. 2019). Here, we hypothesized that airway NE also compartmentalizes within EVs in CF patients.

Methods

To avoid potential aggregation and purification biases, we gently sorted EVs from CF sputum samples using asymmetrical flow field flow fractionation (aF4). Sputum EV fractions were then subjected to analysis by multi-angle light scattering, nanoparticle tracking analysis and flow cytometry.

Results

Multi-angle light scattering and nanoparticle tracking analyses demonstrate the presence of EVs of different sizes ranging from 40–500 nm, with a concentration of ~5 × 107 EVs/mL. EVs were separated by size with aF4 and downstream flow cytometry analysis showed that discrete subfractions concentrate NE on their surface, but that NE burden was not proportional to size.

Conclusions

Our data show that there are discrete subtypes of EVs released by neutrophils carrying various amounts of NE on their surface. These findings provide evidence for a role of EVs in promoting inflammation in the lungs of patients with CF.
Anti-CD11b antibody treatment suppresses the disease conditions in rheumatoid arthritis (RA)-prone, FcγRIIB-deficient mice
Authors: Takahashi Kazuko , Ohtsuji Mareki , Lin Qingshun , Okazaki Hideki , Amano Hirofumi , Yagita Hideo , Nishimura Hiroyuki , Hirose Sachiko
Published: January 2023

Previously we established a RA-prone, FcγRIIB deficient mouse strain (KO1). Anti-mouse CD11b mAb (5C6) has been reported to inhibit the recruitment of CD11b+ myelomonocytic cells from the blood to the inflammatory site. The CD11b+ cells include neutrophils and monocytes, both of which are known to play important roles in the development of RA. In this study, we treated KO1 mice with 5C6 mAb to examine its effects on RA development.

Four-month-old preclinical KO1 mice were treated for 6 months; with 5C6, rat IgG as a control, or none. Among the 3 groups of mice, the severity of RA and immunological abnormalities were compared. RA-related factors in the ankle joints, spleens, and peripheral blood cells were examined.

The 5C6 treatment ameliorated the conditions of RA in KO1 mice, along with the decreases in inflammatory-cell infiltration and osteoclast formation. Transcriptional level analysis for the ankle joints showed that the 5C6 treatment down-regulated the expressions of RANK, RANKL, MCP-1, RANTES, TNFα, and IL-6; and up-regulated that of osteoprotegerin, the decoy receptor for RANKL. Suppression of RA was associated with the lower serum level of autoantibodies, and the decreased frequency of activated B cells. Expressions of B-cell stimulating cytokines were suppressed in the spleens and peripheral leukocytes of the 5C6-treated mice. While untreated KO1 mice spontaneously developed marked monocytosis, the frequency of monocytes was significantly downregulated in the 5C6-treated mice.

It is thought that the 5C6-mediated suppression of RA is caused by the decreased numbers of inflammatory cells and monocytes per se at the joints; also secondarily by the reduced amounts of B-cell stimulating cytokines, leading less autoantibodies.
Leukotriene B4 is required for inflammasome activation
Authors: Salina Ana , Brandt Stephanie , Medeiros Alexandra Ivo , Serezani Henrique
Published: January 2023

BACKGROUND

The events that initiate inflammatory responses during infections are not well understood. The lipid mediator leukotriene B4 (LTB4) is produced within seconds to minutes after phagocyte challenge and emerging evidence shown that LTB4 increases antimicrobial effector functions and inflammatory mediators, such as IL1b. Inflammasomes are intracellular platforms required for the secretion of IL1B/IL18 and an inflammatory cell death termed pyroptosis. Whether LTB4 enhances inflammasome-dependent IL1b secretion remains to be fully understood. Here, we hypothesize that LTB4 enhances inflammasome assembly and release of IL1b in macrophages during infection and sterile inflammation.

METHODOLOGY AND RESULTS

To assess whether LTB4 is required for IL1b and pyroptosis in vivo, the skin of WT and LTB4R1−/− (BLT1) mice were infected with S. aureus for 24 h and biopsies were collected. To track inflammasome/IL1b production overtime, we treated IL1bDsRed mice as well as inflammasome reporter macrophages (ASC-cerulean) with a BLT1 antagonist. Using both genetic and pharmacological BLT1 blockage, we detected decreased IL1b production when compared to infected WT animals. A role for LTB4 in inflammasome activation was confirmed by detection of decreased caspase1 activation, ASC/NLRP3 assembly and gasdermin D (an initiator of pyroptosis) cleavage in vivo and in vitro in BLT1 deficient mice.

CONCLUSION

Our data show that LTB4 is necessary for inflammasome activation and blocking BLT1 actions might be a broad and practical approach to inhibit inflammatory diseases induced by exaggerated inflammasome activation.
The phosphorylation kinetics of the key regulators in T cell receptor signaling pathway
Authors: An Wei , Park Kyueon , Reyes Alfonso , Kwieraga Amanda , Sabri Nazila , Frey Avery , Chronopoulou Efthalia , Savas-Carstens Jan , Soper David , Elia Jeanne , Li Michael , Yang Xifeng
Published: January 2023

T cell receptor (TCR) signaling pathway regulates T cell homeostasis and adaptive immune responses. Clinically, the activation of TCR is indispensable to the success of T cell-based immunotherapy. The engagement of TCR phosphorylates immunoreceptor tyrosine-based activation motifs (ITAM) on CD3, which is followed by a protein phosphorylation cascade. Protein phosphorylation, regulated by kinases and phosphatases, changes protein conformation and determines protein function. A better understanding of TCR signaling phosphorylation events is crucial to both decipher the T cell regulation mechanism and boost the efficacy of T cell immunotherapy. Here, we developed a panel of monoclonal antibodies that target several of the TCR signaling regulators and are applicable for both intracellular flow cytometry (ICFC) and western blot (WB). Using these antibodies, we performed a kinetic analysis of the TCR signaling pathway. Jurkat T cells were cross-linked by soluble anti-CD3 and anti-CD28 antibodies, and the phosphorylation kinetics of the key TCR signaling regulators, such as phospho-ZAP-70 and phospho-PLCg1, were evaluated by ICFC and WB. We show that TCR signaling activation induced by cross-linking CD3 and CD28 is a relatively transient event and the optimal activation of the key TCR signaling regulators varies from 1 to 15 minutes. Our data profiled the phosphorylation kinetics of the key regulators in TCR signaling pathway.
The biological function of naturally occurring DOCK2 inhibitor in tissue-specific immune evasion
Authors: Sakurai Tetsuya , Uruno Takehito , Fukui Yoshinori
Published: January 2023

Study objection

DOCK2 is a Rac-specific guanine nucleotide exchange factor (GEF) predominantly expressed in hematopoietic cells. DOCK2 is essential for migration and activation of leukocytes, and its mutations in humans cause severe immunodeficiency, thereby indicating that DOCK2 plays a key role in immune surveillance. Interestingly, however, we found that a naturally occurring DOCK2 inhibitor exists in our body and named this molecule DOCK2 inhibitory metabolite (D2IM). In this study, we aimed to reveal biological functions of D2IM.

Method

The specificity of D2IM was examined with Rac GEF assay and binding assay. T cells and neutrophils from WT mouse were treated with D2IM and subjected to Rac activation assay and chemotaxis assay. D2IM production in various tissues was monitored with mass spectrometry. In addition, influence of the lack of CS on ultraviolet- and antigen-induced ocular inflammationwas analyzed using KO mice lacking D2IM synthase.

Result

CS inhibited the Rac GEF activity of murine DOCK2 protein in vitro with a IC50 value of 2.0 mM. When leukocytes were treated with D2IM, chemoattractant-induced Rac activation was severely impaired, resulting in a marked reduction of migratory response of lymphocytes and neutrophils. D2IM most abundantly existed in the Harderian gland, which produces lipids to form the oily layer of the tear film, and its production was completely lost in mice lacking D2IM synthase. We found that the lack of D2IM augmented ultraviolet- and antigen-induced ocular inflammation in mice, which was suppressed by administration of eye drops containing D2IM.

Conclusion

D2IM is a naturally occurring DOCK2 inhibitor that contributes to create immune evasive microenvironment in the eye.
Functional Nrf2 restrains inflammatory and transcriptional phenotypes in microglia and its deficiency recapitulates the aging phenotype
Authors: Yu I-Chen Ivorine , Paraiso Hallel C , Kuo Ping-Chang , Scofield Barbara A. , Sweazey Robert D. , Chang Fen-Lei , Yen Jui-Hung
Published: January 2023

Microglia (MG) represent plastic myeloid cells resident in the brain that can dynamically respond to changes of local microenvironment and stimuli from the periphery. Dysfunctional microglial responses are thought to worsen the pathogenesis of neurodegeneration. The nuclear factor (erythroid-derived 2) - like 2 (Nrf2) protein is a transcription factor that regulates expressions of antioxidant and stress defense genes. Here, we reported that chronic Nrf2 deficiency in MG leads to neuroinflammation and Alzheimer’s disease-like cognitive impairment during aging. The Nrf2 transcript was downregulated in MG from the middle-aged (12 months-old) and aged (24 months-old) brain. Loss of Nrf2 primed MG towards inflammatory phenotype as revealed the significant increase of Clec7a and CD68 markers. Middle-aged Nrf2 knockout (Nrf2−/−) mice showed elevated reactive MG, proinflammatory cytokines, and infiltrating immune cells in the brain, and resembled Alzheimer’s disease like-cognitive impairment in aged mice. Nrf2−/− MG showed increased nuclear NF-κB p65 and CD86 at the resting state, whereas the reduced induction of CD206, Ym1, and Fizz1 after IL-4 stimulation. These results suggested that Nrf2-deficient MG are primed toward inflammatory phenotypes and resistant to the anti-inflammatory modulation. In addition, loss of Nrf2 resulted in downregulation of homeostatic signatures in MG, such as P2ry12, Tmem119, Gpr34, Tgfbr1, and Mafb, suggesting the importance of Nrf2 signaling to regulate microglial homeostasis. Overall, our results demonstrated that functional decline of Nrf2 results in dysregulated phenotypes in MG, which may lead to extravagant neuroinflammation and impaired cognition in aging and Alzheimer’s disease.
Lymphopenia and bone marrow T cell sequestration accompanying stroke are mediated by T cell S1P1 loss
Authors: Wilkinson Daniel S , Dechant Cosette , Chongsathidkiet Pakawat , Wang Haichen , Kemeny Hanna , Laskowitz Daniel , Fecci Peter
Published: January 2023

Sequestration of T cells in bone marrow is a phenomenon recently characterized by our group in the setting of intracranial tumors, regardless of histology. It is accompanied by lymphopenia and lymphoid organ regression and is mediated by loss of S1P1 receptor from the T cell surface. We now reveal that this phenomenon is not unique to tumors, but accompanies additional intracranial pathologies, most notably stroke. In this study, blood, bone marrow, and spleens were collected from mice at day 2, 5, 7 or 14 following stroke via middle cerebral artery occlusion (MCAO) or sham surgery and analyzed by flow cytometry. T cell S1P1 levels were assessed, as were T cell counts in each compartment. S1P1 receptor stabilization was achieved with a knock-in model in which receptor internalization is inhibited. Following stroke, T cells accumulated in the bone marrow of injured mice. T cell numbers peaked at day 7 post-stroke before returning to normal by day 14. Bone marrow accumulation was accompanied by transient lymphopenia and splenic involution following stroke. T cells in the bone marrow yielded decreased levels of S1P1 on their surface. Conversely, mice with genetically stabilized T cell S1P1 protected against sequestration, lymphopenia, and splenic regression following stroke. In conclusion, bone marrow T cell sequestration occurs transiently following stroke and is mediated by the S1P-S1P1 axis. This may be prove an adaptive mechanism to limit intracranial inflammation following an initial insult. Better understanding of this phenomenon may uncover a novel mechanism of immune privilege and allow for therapeutic modulation in the setting of stroke, brain tumor, and other types of intracranial injury.
Hypoxia-Inducible Factors (HIF) in CD4+ T cells promote metabolism, switch cytokine secretion, and T cell help in humoral immunity
Authors: Cho Sung Hoon , Raybuck Ariel , Kemboi Edna , Haase Volker , Boothby Mark Robin
Published: January 2023

T cell help in humoral immunity includes interactions of B cells with activated extrafollicular CD4+ and follicular T helper (Tfh) cells. Each can promote antibody responses but Tfh cells play critical roles during germinal center (GC) reactions. After re-stimulation of their antigen receptor (TCR) by B cells, helper T cells act on B cells via CD40 ligand and secreted cytokines that guide immunoglobulin class switching. Recent work showed that hypoxia is a normal feature of most GC, raising questions about molecular mechanisms governing the relationship between hypoxia and T cell help to antibody response. Hypoxia-inducible factors (HIF) are prominent among mechanisms that mediate cellular responses to limited oxygen but also are induced by lymphocyte activation. We now show that loss of HIF-1a and HIF-2a in CD4+ T cells compromised essential functions in help during antibody responses. HIF-1a depletion from CD4 T cells reduced frequencies of antigen-specific GC B cells, Tfh cells, and overall antigen-specific Ab. Compound deficiency of HIF-1a and HIF-2a intensified humoral defects after hapten-carrier immunization. Further, HIF promoted CD40L expression while restraining the FoxP3-positive CD4+ cells in the CCR5+ follicular regulatory (Tfr) population. Glycolysis increases T helper cytokine expression, and HIF was essential for stimulation of glycolysis in T helper cells via TCR or cytokine stimulation, as well as their production of cytokines that direct antibody class switching. Indeed, interferon-g elaboration by HIF-deficient in vivo-generated Tfh cells was impaired. Collectively, the results indicate that HIF transcription factors are vital components of the mechanisms of follicular help during humoral responses.
Transcription coactivator OCA-B mediates interactions between target loci in T cells and is sufficient to promote CD4 memory in vivo
Authors: Tantin Dean R , Zhao Keiji , Williams Matthew A , Hale J Scott , Lai Binbin , Ren Gang , Kim Heejoo
Published: January 2023

Stable epigenetic changes occurring during T cell activation are crucial for the generation of immunological memory. In CD4 T cells, OCA-B (Pou2af1/OBF-1/Bob.1) promotes poised gene expression states in an array of direct immunomodulatory target genes (e.g. Il2, Il21 and Ifng) via the recruitment of the histone lysine demethylase Jmjd1a/Kdm3a. Our prior work indicates that OCA-B is not expressed in naïve CD4 T cells, but becomes stably expressed upon persistent antigen exposure. OCA-B is also critical for the generation of functional CD4 memory T cells in response to pathogen infection. By ectopically expressing OCA-B in SMARTA TCR transgenic T cells and co-transferring transduced T cells together with empty vector controls, we show that OCA-B does not affect primary effector responses, but is sufficient to promote formation of long-lived memory T cells. Although there are no differences in T cell numbers or function, the promotion of memory is preceded in the effector phase by changes in the expression of surface markers such as CD62L, ICOS and PD-1. We identify a mode of transcription regulation by OCA-B in T cells in which OCA-B facilitates communication between target loci such as Il2 and Il21. These results indicate that expressing OCA-B may be useful as a method of enhancing CD4 memory.