Higher Levels Of CXCL10 Research Articles

High serum levels of CXCL13 predict lower response to csDMARDs in both ACPA-positive and ACPA-negative early rheumatoid arthritis.

Increased circulating levels of CXCL13 reflect synovial production and indicate immune dysregulation in patients with rheumatoid arthritis (RA). Here we tested whether CXCL13 predicts response to first-line treatment with methotrexate (MTX) in patients with early RA, independently and in association with anti-citrullinated protein antibodies (ACPA) and IgM-rheumatoid factor (RF). A prospective cohort of 243 early RA patients undergoing treat-to-target with MTX was evaluated. CXCL13, ACPA and IgM-RF were determined on baseline sera. Short-term variations of CXCL13 were measured after 2 months. The association of high CXCL13 (≥100 pg/ml) with disease remission after 6 months and escalation to second-line therapies within year 2 was evaluated in the total population and in ACPA-subgroups separately. High levels of CXCL13 were found in 53.6% of ACPA-positive and 31.5% of ACPA-negative patients, with minimal association with disease activity and RF. Serum CXCL13 remained stable after 2 months. High baseline CXCL13 independently predicted failure to achieve remission and more frequent requirement of second-line treatment in ACPA-positive patients, with adjusted ORs in the range of 0.17-0.49 for remission and 6.75 for second-line treatment. In ACPA-negative patients with high CXCL13, remission occurred at the expense of higher doses of MTX, and levels of CXCL13 predicted MTX escalations with an adjusted OR (95% CI) of 2.69 (1.35-5.34). High serum levels of CXCL13 identify a subgroup of RA patients who are more refractory to first-line treatment with MTX. CXCL13 appears a promising biomarker of response to MTX in both ACPA-positive and -negative early RA.

Acute and chronic impact of interleukin-33 stimulation on chemokines and growth factors in human cord blood-derived mast cells.

Mast cells (MCs) are multifaceted immune cells that are capable of recognizing and responding to various stimuli by releasing an array of cytokines. We aimed to use human cord blood-derived mast cells (hCBMCs) as a model to evaluate different conditions under which chemokines and growth factors are expressed and secreted as mediators upon stimulation with the alarmin interleukin-33 (IL-33). hCBMCs were stimulated with 10 ng/mL or 20 ng/mL of recombinant human IL-33 (rhIL-33) for 6 h (acute) or 24 h (chronic). The mRNA expression of chemokines and growth factors was analyzed using microarrays, and the mediators released in the supernatant were evaluated using a multiplex assay. The mRNA expression levels of C-C chemokine ligands (CCL) CCL1, CCL5, granulocyte macrophage colony-stimulating factor (GM-CSF), and macrophage inflammatory protein (MIP)-4/CCL18 were upregulated under all conditions. In contrast, C-X-C motif chemokine ligand (CXCL) CXCL8 and CCL24 levels increased only under acute (6 h) and prolonged (24 h) conditions, respectively. Moreover, high levels of CXCL8, MIP-1α, and MIP-1β were secreted during acute inflammation, whereas the release of GM-CSF and CXCL9 proteins increased under all four conditions. This study highlights the sentinel role of MCs in mounting a specific immune response against a pathogenic-like stimulus in a timely and dose-dependent manner and is relevant for improving inflammatory treatment options.

CXCL10 predicts autoimmune features and a favorable clinical course in patients with IIP: post hoc analysis of a prospective and multicenter cohort study

BackgroundInterstitial pneumonia with autoimmune features (IPAF), which does not meet any of the criteria for connective tissue diseases (CTD), has been attracting an attention in patients with idiopathic interstitial pneumonia (IIP). However, the biomarkers that reflect the clinical course of these patients have not been fully elucidated.ObjectiveTo identify useful serum biomarkers reflecting CTD-related features and favorable prognoses in patients with IIP.MethodsThis was a post hoc analysis of a prospective and multicenter cohort study between 2015 and 2020. Newly diagnosed patients with IIP were consecutively enrolled, and 74 autoimmune features and autoantibodies were comprehensively checked during IIP diagnosis. Serum levels of CXCL10, CXCL1, CCL2, BAFF, angiopoietin-2, and leptin were evaluated at the time of IIP diagnosis.ResultsTwo hundred twenty-two patients (159 men and 63 women) with IIP were enrolled. The median observation duration was 36 months. The median age was 71 years old, and median %forced vital capacity (FVC) was 84.1% at the time of IIP diagnosis. The proportion of patients who met the classification criteria for IPAF was 11.7%. In patients with high serum CXCL10, changes in both %FVC and %diffusion lung capacity for carbon monoxide at one year were significantly higher than those in patients with low CXCL10 (p = 0.014 and p = 0.009, respectively), whereas these changes were not significant for other chemokines and cytokines. High CXCL10 levels were associated with acute/subacute onset (p < 0.001) and the diagnosis of nonspecific interstitial pneumonia with organizing pneumonia overlap (p = 0.003). High CXCL10 levels were related to a higher classification of IPAF (relative risk for IPAF was 3.320, 95%CI: 1.571–7.019, p = 0.003) and lower classification of progressive pulmonary fibrosis (PPF; relative risk for PPF was 0.309, 95%CI: 0.100-0.953, p = 0.027) compared to those with low CXCL10. Finally, survival was higher in patients with IPF and high CXCL10 (p = 0.044), and high CXCL10 was a significant prognostic factor in multivariate Cox proportional hazards models (hazard ratio 0.368, p = 0.005).ConclusionsHigh serum levels of CXCL10 are associated with CTD-related features, the favorable clinical course, and survival in patients with IIP, especially IPF.Clinical trial numberNot applicable.

Genetically Predicted Association of 91 Circulating Inflammatory Proteins with Multiple Sclerosis: A Mendelian Randomization Study.

Previous studies have validated a close association between inflammatory factors and multiple sclerosis (MS), but their causal relationship is not fully profiled yet. This study used Mendelian randomization (MR) to investigate the causal effect of circulating inflammatory proteins on MS. Data from a large-scale genome-wide association study (GWAS) were analyzed using a two-sample MR method to explore the relationship between 91 circulating inflammatory proteins and MS. The inverse-variance-weighted (IVW) analysis was employed as the main method for evaluating exposures and outcomes. Furthermore, series of the methods of MR Egger, weighted median, simple mode, and weighted mode were used to fortify the final results. The results of the IVW method were corrected with Bonferroni (bon) and false discovery rate (fdr) for validating the robustness of results and ensuring the absence of heterogeneity and horizontal pleiotropy. The sensitivity analysis was also performed. The results of the forward MR analysis showed that higher levels of CCL25 were found to be associated with an increased risk of MS according to IVW results, OR: 1.085, 95% CI (1.011, 1.165), p = 2.42 × 10-2, adjusted p_adj_bon = 1, p_adj_fdr = 0.307. Similarly, higher levels of CXCL10 were found to be associated with an increased risk of MS, OR: 1.231, 95% CI (1.057, 1.433), p = 7.49 × 10-3, adjusted p_adj_bon = 0.682, p_adj_fdr = 0.227. In contrast, elevated levels of neurturin (NRTN) were associated with a decreased risk of MS, OR: 0.815, 95% CI (0.689, 0.964), p = 1.68 × 10-2, adjusted p_adj_bon = 1, p_adj_fdr = 0.307. Reverse MR analysis showed no causal relationship between MS and the identified circulating inflammatory cytokines. The effects of heterogeneity and level pleiotropy were further excluded by sensitivity analysis. This study provides new insights into the relationship between circulating inflammatory proteins and MS and brings up a new possibility of using these cytokines as potential biomarkers and therapeutic targets. The data in this study show that there are only weak associations between inflammatory molecules and MS risk, which did not survive bon and fdr correction, and the obtained p-values are quite low. Therefore, further studies on larger samples are needed.

Circulating Chemokines and Short- and Long-Term Outcomes After Ischemic Stroke

AbstractChemokines are vital in post-cerebral ischemia inflammatory reactions. We investigate the possible relationship between plasma chemokines and short-term and long-term outcomes after stroke. This study included 235 patients (median age, 72 years; 49.8% female) suffering from ischemic stroke, or transient ischemic attack admitted to the hospital within 24 h of onset. We evaluated chemokines CCL2, CCL5, CXCL8, CXCL9, and CXCL10 in plasma samples collected upon admission. Further, we assessed functional outcomes at 3- and 12-months, all-cause fatality over 5 years, and episodes of delirium within the first 7 days of admission. Multivariate analysis revealed an association between higher CXCL10 levels and an increased risk of poor functional outcomes at 3 months (OR: 3.02, 95%CI: 1.22–7.46, p = 0.016) and 12 months (OR: 2.32, 95%CI: 1.03–5.26, p = 0.043), as well as an increased death risk (HR: 1.79, 95%CI: 1.04–3.07, p = 0.036). High CXCL8 levels independently predicted poor functional outcomes at 12 months (OR: 2.69, 95%CI: 1.39–6.31, p = 0.005) and a higher 5-year case fatality rate (HR: 1.90, 95%CI: 1.23–2.93, p = 0.004). Elevated CXCL9 levels also predicted unfavourable functional outcomes at 12 months (OR: 2.45, 95%CI: 1.07–5.61, p = 0.034). In univariate analysis, increased levels of CXCL8, CXCL9, and CXCL10 showed an association with delirium, although this link was not evident in the multivariate analysis. Plasma CXCL8 and CXCL10 show potential as prognostic biomarkers for stroke outcomes and as therapeutic targets suitable for reverse translation.

Modulation of the Immunological Milieu in Acute Aneurysmal Subarachnoid Hemorrhage: The Potential Role of Monocytes Through CXCL10 Secretion.

Emerging evidence indicates that aneurysmal subarachnoid hemorrhage (aSAH) elicits a response from both innate and adaptive immune systems. An upregulation of CD8 + CD161 + cells has been observed in the cerebrospinal fluid (CSF) after aSAH, yet the precise role of these cells in the context of aSAH is unkown.CSF samples from patients with aSAH and non-aneurysmal SAH (naSAH) were analyzed. Single-cell RNA sequencing (scRNAseq) was performed on CD8 + CD161 + sorted samples from aSAH patients. Cell populations were identified using "clustering." Gene expression levels of ten previously described genes involved in inflammation were quantified from aSAH and naSAH samples using RT-qPCR. The study focused on the following genes: CCL5, CCL7, APOE, SPP1, CXCL8, CXCL10, HMOX1, LTB, MAL, and HLA-DRB1. Gene clustering analysis revealed that monocytes, NK cells, and T cells expressed CD8 + CD161 + in the CSF of patients with aSAH. In comparison to naSAH samples, aSAH samples exhibited higher mRNA levels of CXCL10 (median, IQR = 90, 16-149 vs. 0.5, 0-6.75, p = 0.02). A trend towards higher HMOX1 levels was also observed in aSAH (median, IQR = 12.6, 9-17.6 vs. 2.55, 1.68-5.7, p = 0.076). Specifically, CXCL10 and HMOX1 were expressed by the monocyte subpopulation. Monocytes, NK cells, and T cells can potentially express CD8 + CD161 + in patients with aSAH. Notably, monocytes show high levels of CXCL10. The elevated expression of CXCL10 in aSAH compared to naSAH indicates its potential significance as a target for future studies.

Serum CXCL13 level is related to treatment response and predicts disease prognosis in Waldenström macroglobulinemia.

Waldenström macroglobulinemia (WM) is a type of B-cell lymphoma that produces IgM. Our study aimed to investigate the role of CXCL13, a chemokine essential for B lymphocytes, in the evaluation of treatment response and prognosis in WM. We collected serum samples and clinical data from 72 WM patients, with 69 patients receiving systemic therapy and 3 patients opting not to receive treatment. Serum CXCL13 levels at baseline and after six months of treatments were measured by enzyme-linked immunosorbent assay. The median serum level of CXCL13 was 1 539.2pg/ml (range 10.0-21 389.9) at baseline and significantly decreased to 123.1pg/ml (range 0.0-6741.5) after 6months of treatments. At baseline, higher CXCL13 levels were associated with lower hemoglobin levels (p = 0.001), higher β2-microglobulin levels (p = 0.001), lower albumin levels (p = 0.046), and higher IPSS-WM scores (p = 0.013). After 6months of treatment, patients who achieved PR/VGPR had significantly lower CXCL13 levels compared to those with SD (70.2pg/ml vs 798.6pg/ml, p = 0.002). The median follow-up period was 40months (range 4.2-188). Eight patients died during the follow-up period. Overall survival differed based on CXCL13 levels. When grouped by baseline CXCL13 levels, the median OS was 60.0months in patients with serum CXCL13 > 2 000pg/ml, while it was not reached in patients with low CXCL13 levels (p < 0.001). Based on CXCL13 levels after the treatments, the median OS was 74.0months in patients with serum CXCL13 > 200pg/ml, while it was not reached in patients with CXCL13 ≤ 200pg/ml. In a subgroup of 28 patients with a series of serum samples, the increase of serum CXCL13 level was associated with disease progression or the start of next-line therapy (p < 0.001). Our study concludes that serum CXCL13 levels decrease in WM patients treated with various regimens and correlate with treatment response. Detecting serum CXCL13 at baseline or after treatment help in predicting prognosis.

Interferon-α induces differentiation of cancer stem cells and immunosuppression in hepatocellular carcinoma by upregulating CXCL8 secretion

Interferon-alpha (IFN-α) is widely used in the clinical treatment of patients with chronic hepatitis B and hepatocellular carcinoma (HCC). However, high levels of CXCL8 are associated with resistance to IFN-α therapy and poorer prognosis in advanced cancers. In this study, we investigated whether IFN-α could directly induce the production of CXCL8 in HCC cells and whether CXCL8 could antagonize the antitumor activity of IFN-α. We found that IFN-α not only upregulated the expression of the inducible genes CXCL9, CXCL10, CXCL11 and PD-L1, but also significantly stimulated CXCL8 secretion in HCC cells. Mechanically, IFN-α induces CXCL8 expression by activating the AKT and JNK pathways. In addition, our results demonstrate that IFN-α exposure significantly increases the differentiation of HCC stem cells, but this effect is reversed by the addition of the CXCL8 receptor CXCR1/2 inhibitor Reparixin and STAT3 inhibitor Stattic. Besides, our study reveals that the cytokine CXCL8 secreted by IFN-α-induced HCC cells inhibits T-cell function. Conversely, inhibition of CXCL8 promotes TNF-α and IFN-γ secretion by T cells. Finally, liver cancer patients who received anti-PD-1/PD-L1 immunotherapy with high CXCL8 expression had a lower immunotherapy efficacy. Overall, our findings clarify that IFN-α triggers immunosuppression and cancer stem cell differentiation in hepatocellular carcinoma by upregulating CXCL8 secretion. This discovery provides a novel approach to enhance the effectiveness of HCC treatment in the future.

Evaluation of Proinflammatory Chemokines in HIV Patients with Asymptomatic Leishmania Infantum Infection.

Asymptomatic Leishmania infantum, when associated with HIV, can become severe and potentially fatal. In this co-infection, the worst prognosis may be influenced by the host's immunological aspects, which are crucial in determining susceptibility. Chemokines play an important role in this process by influencing the cellular composition at affected sites and impacting the disease's outcome. Therefore, the aim of this study was to evaluate proinflammatory chemokines in HIV patients with the asymptomatic L. infantum infection. In this cross-sectional study, the levels of CCL2, CCL5, CXCL8, MIG, and IP-10 were measured in 160 serum samples from co-infected patients (n = 53), patients with HIV (n = 90), and negative controls (n = 17). Quantification was determined by flow cytometry. The obtained data were statistically analyzed using the Kruskal-Wallis test, followed by the Dunn's post-test and the Spearman's correlation coefficient. Significance was set at p < 0.05. The chemokines CCL2, CCL5, MIG, and IP-10 exhibited higher levels in the HIV group compared to co-infection. However, the elevated levels of all these chemokines and their increased connectivity in co-infected patients appear to be important in identifying proinflammatory immune responses associated with the asymptomatic condition. Furthermore, a weak negative correlation was observed between higher levels of CXCL8 and lower viral loads in co-infected patients.

Inflammatory factors and risk of meningiomas: a bidirectional mendelian-randomization study.

Meningiomas are one of the most common intracranial tumors, and the current understanding of meningioma pathology is still incomplete. Inflammatory factors play an important role in the pathophysiology of meningioma, but the causal relationship between inflammatory factors and meningioma is still unclear. Mendelian randomization (MR) is an effective statistical method for reducing bias based on whole genome sequencing data. It's a simple but powerful framework, that uses genetics to study aspects of human biology. Modern methods of MR make the process more robust by exploiting the many genetic variants that may exist for a given hypothesis. In this paper, MR is applied to understand the causal relationship between exposure and disease outcome. This research presents a comprehensive MR study to study the association of genetic inflammatory cytokines with meningioma. Based on the results of our MR analysis, which examines 41 cytokines in the largest GWAS datasets available, we were able to draw the relatively more reliable conclusion that elevated levels of circulating TNF-β, CXCL1, and lower levels of IL-9 were suggestive associated with a higher risk of meningioma. Moreover, Meningiomas could cause lower levels of interleukin-16 and higher levels of CXCL10 in the blood. These findings suggest that TNF-β, CXCL1, and IL-9 play an important role in the development of meningiomas. Meningiomas also affect the expression of cytokines such as IL-16 and CXCL10. Further studies are needed to determine whether these biomarkers can be used to prevent or treat meningiomas.

Tertiary lymphoid structure prevalence and prognostic value in cervical cancer.

e17521 Background: Recurrent or progressive cervical cancer have limited second-line treatment options. Response rates are often poor to second-line therapy (average response rate of 15%). Identification of factors which predict response to immunotherapy and targets to enhance the immune response are critically needed in cervical cancer. Chronic inflammation can initiate an immune response in non-secondary lymphoid organs (SLO) and form a Tertiary Lymphoid Structure (TLS). TLS is composed of immune cells clustered and organized and responsible for immune cell chemotaxis, which impacts cancer therapeutic response. Chemokine ligand 13 (CXCL13) is related to B cell attraction and TLS formation. Recent work from our group demonstrated human papilloma virus (HPV) positive head and neck squamous cell carcinoma (HNSCC) exhibited greater tumor infiltrating B cells (TIL-Bs) and TLS vs HPV negative disease indicating a role for viral infection in immune infiltration. Most cervical cancer is caused by HPV infection, therefore we investigated prognostic significance of immune infiltration in cervix cancer. Methods: A cohort analysis was conducted on 43 patients diagnosed with early stage cervical cancer. The presence of B cells, CD8 T cells, and CXCL13 was analyzed using singleplex immunohistochemistry staining. We separated infiltration into high infiltration and low infiltration, defined by their median value. TLS was identified using a multiplex immunofluorescence for TLS maturity panel. Histological findings were associated with cohort data. Results: High intratumoral infiltration of CD8 T cells was associated with longer overall survival in cancer patients. Median survival was 45 months for low infiltration group, whereas it was not reached by higher T cell infiltration (p &lt; 0.05). The prognostic value of T cell infiltration was stronger in adenocarcinoma, typically associated with worse outcomes, than in squamous cell carcinoma. In adenocarcinoma, median survival was 58 months for low T cell infiltration, it was not reached by high infiltration group. CXCL13 levels were prognostic for recurrence-free survival, with median survival of 53 months in low expression group and not reached in high CXCL13 presence group (p &lt; 0.05). The presence of TLS compared to low B cell infiltration was associated to higher survival, with 0% of deaths in the TLS group vs 40% in low B cell infiltration. While there was no correlation between TIL-B and patient outcomes, the presence of B cells in the aggregation process and higher CXCL13 levels were associated with improved survival, with 9% deaths vs 36% in low B cell group, possibly due to the support of TLS formation by B cell aggregation surrounded by CXCL13. Conclusions: Our study suggests that the presence of TLS, whether forming or established, is linked to improved clinical outcomes in cervical cancer. Further research is necessary to investigate the response of this cancer type to immunotherapy.

Single-cell characterization of circulating and synovial immune cells reveals a unique dendritic cell landscape and enrichment of granzyme K+ T cells in Psoriatic Arthritis.

Abstract Psoriatic Arthritis (PsA) is an immune mediated disease of the joint. It typically develops within 10 years after the onset of psoriasis, with ~30% of individuals progressing to joint disease. The progression of disease from skin to joint is not fully understood, although it is thought to be orchestrated by T helper 17 immune responses. To understand the immune landscape of PsA, we isolated immune cells from four matched PsA patient blood and synovium samples and performed multimodal single-cell sequencing (ExCITE-seq), which captures surface epitope information and T and B cell receptor rearrangement in addition to transcriptional profile. Our preliminary analysis revealed an enrichment of CD1c+/CD141+ dendritic cells (DCs) in synovium compared to the blood of PsA patients. Differential gene expression of these DC populations showed increased expression of CXCL16 in synovium derived DCs, while analysis of synovial fluid revealed high levels of CXCL10. Differential gene expression of CD8 and CD4 T cells across blood and synovium revealed increased granzyme K (GZMK) in the synovium. Further analyses comparing the GZMK+ T cell populations to their negative counterparts revealed upregulation of CXCR3, suggesting that CXCR3-CXCL10 axis may be responsible for recruitment and/or retention of T cells in the synovium. Pathway analysis for GZMK+ T cells revealed increased cytotoxicity and granulitic activity. Together this data suggests that GZMK+ T cells may contribute to inflammation in the joint of PsA patients, after recruitment to the site of inflammation by CD1c+/CD141+ DCs. Further characterization of additional PsA patients and psoriasis patients at risk for developing PsA is ongoing and will provide insight into PsA pathogenesis. Supported by a grant from the NIH (I&amp;I Schwab T32) and funding from the National Psoriasis Foundation and the Colton Center for Autoimmunity.

Abstract 1124: PTEN loss confers resistance to anti-PD-1 therapy in NSCLC by increasing tumor infiltration of T regulatory cells

Abstract Immune checkpoint inhibitors (ICIs) targeting PD-L1/PD-1 have dramatically improved the management of NSCLC patients. Nevertheless, more than 50% patients will present primary resistance or will develop secondary resistance within 12-25 months after treatment initiation. The mechanisms of resistance to ICIs may depend on tumor-intrinsic molecular/genetic alterations that generate an immunosuppressive tumor microenvironment (isTME). Using In silico analyses (TCGA and AACR-GENIE cohorts), and protein expression analysis in our institutional CIMA-CUN cohort, we have shown that &amp;gt;50% LUSC and ~28% LUAD tumors exhibited reduced PTEN mRNA/protein levels. Patients with PTEN-low tumors had higher levels of CXCL10, PD-L1 and PD-L2. In a cohort of stage IV NSCLC patients treated with ICIs, we found that patients with low tumor PTEN levels were significantly associated with worse OS (p=0.021). We have developed and characterized a Pten-null LUSC model using UN680 cells, which was also refractory to anti-PD-1 when implanted in syngeneic mice. Pten loss led to a deregulation of multiple pathways related to immunosuppression, with a positive enrichment in “IL-6/JAK/STAT3” and “TNF-α via NFkB” hallmarks, identified by GSEA. Tumors from the Pten-null LUSC model were highly metastatic and fibrotic, and secreted TGF-β/CXCL10, thus favoring conversion of CD4+ lymphocytes into Tregs. Human/mouse PTEN-low tumors were enriched in Tregs and immunosuppressive genes. Importantly, treatment of mice bearing Pten-null tumors with TLR agonists+anti-TGF-β, aimed to alter this isTME, led to tumor rejection and immunological memory in 100% of mice. Our results demonstrate that lack of PTEN causes immunotherapy resistance in LUSC by establishing an isTME that can be reversed therapeutically. Citation Format: Francisco Exposito, Miriam Redrado, Maeva Houry, Katherine Hastings, Magdalena Molero-Abraham, Teresa Lozano, Jose L. Solorzano, Julian Sanz Ortega, Vera Andradas, Ramon Amat, Esther Redin, Sergio Leon, Naroa Legarra, Javier García, Diego Serrano, Karmele Valencia, Camila Robles-Oteiza, Giorgia Foggetti, Enriqueta Felip, Juan J. Lasarte, Luis Paz-Ares, Jon Zugazagoitia, Katerina Politi, Luis M Montuenga, Alfonso Calvo. PTEN loss confers resistance to anti-PD-1 therapy in NSCLC by increasing tumor infiltration of T regulatory cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1124.

T peripheral helper cells in autoimmune diseases: What do we know?

The interactions between T cells and B cells are essential for antibody responses and the development of autoimmune diseases. Recently, a distinct subset of T cells capable of helping B cells was established in synovial fluid, and they were termed peripheral helper T (Tph) cells. PD-1hiCXCR5-CD4+ Tph cells express high levels of CXCL13, which drives the formation of lymphoid aggregates and tertiary lymphoid structures, ultimately facilitating the local production of pathogenic autoantibodies. Tph and T follicular helper cells share some key features but can be distinguished by their surface markers, transcriptional regulation, and migration capability. We summarize recent findings on Tph cells in this review and provide a perspective on their potential roles in a range of autoimmune diseases. More clinical and in-depth mechanistic investigations of Tph cells may help to improve the understanding of pathogenesis and further provide novel therapeutic targets in autoimmune diseases.

CXCL13 as a possible immunological surrogate marker of dermatomyositis: higher levels of CXCL13 in dermatomyositis than polymyositis

CXCL13 as a possible immunological surrogate marker of dermatomyositis: higher levels of CXCL13 in dermatomyositis than polymyositis

Human Monocytes Exposed to SARS-CoV-2 Display Features of Innate Immune Memory Producing High Levels of CXCL10 upon Restimulation

Introduction: A role for innate immune memory in protection during COVID-19 infection or vaccination has been recently reported. However, no study so far has shown whether the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can train innate immune cells. The aim of this study was to investigate whether this virus can induce trained immunity in human monocytes. Methods: Monocytes were exposed to inactivated SARS-CoV-2 (iSARS-CoV-2) for 24 h, followed by a resting period in the medium only and a secondary stimulation on day 6 after which the cytokine/chemokine and transcriptomic profiles were determined. Results: Compared to untrained cells, the iSARS-CoV-2-trained monocytes secreted significantly higher levels of IL-6, TNF-α, CXCL10, CXCL9, and CXCL11 upon restimulation. Transcriptome analysis of iSARS-CoV-2-trained monocytes revealed increased expression of several inflammatory genes. As epigenetic and metabolic modifications are hallmarks of trained immunity, we analyzed the expression of genes related to these processes. Findings indicate that indeed SARS-CoV-2-trained monocytes show changes in the expression of genes involved in metabolic pathways including the tricarboxylic acid cycle, amino acid metabolism, and the expression of several epigenetic regulator genes. Using epigenetic inhibitors that block histone methyl and acetyltransferases, we observed that the capacity of monocytes to be trained by iSARS-CoV-2 was abolished. Conclusion: Overall, our findings indicate that iSARS-CoV-2 can induce properties associated with trained immunity in human monocytes. These results contribute to the knowledge required for improving vaccination strategies to prevent infectious diseases.

CXCL13 chemokine is a novel player in multiple myeloma osteolytic microenvironment, M2 macrophage polarization, and tumor progression

BackgroundWe assessed the mechanism by which multiple myeloma (MM) shapes the bone marrow (BM) microenvironment and affects MΦ polarization.MethodsIn vivo xenograft model of BM-disseminated human myeloma, as well as analysis of MM cell lines, stromal components, and primary samples from patients with MM, was utilized.ResultsAnalysis of the BM from MM-bearing mice inoculated with human CXCR4-expressing RPMI8226 cells revealed a significant increase in M2 MΦ cell numbers (p < 0.01). CXCL13 was one of the most profoundly increased factors upon MM growth with increased levels in the blood of MM-bearing animals. Myeloid cells were the main source of the increased murine CXCL13 detected in MM-infiltrated BM. MM cell lines induced CXCL13 and concurrent expression of M2 markers (MERTK, CD206, CD163) in co-cultured human MΦ in vitro. Interaction with MΦ reciprocally induced CXCL13 expression in MM cell lines. Mechanistically, TGFβ signaling was involved in CXCL13 induction in MM cells, while BTK signaling was implicated in MM-stimulated increase of CXCL13 in MΦ. Recombinant CXCL13 increased RANKL expression and induced TRAP+ osteoclast (OC) formation in vitro, while CXCL13 neutralization blocked these activities. Moreover, mice inoculated with CXCL13-silenced MM cells developed significantly lower BM disease. Reduced tumor load correlated with decreased numbers of M2 MΦ in BM, decreased bone disease, and lower expression of OC-associated genes. Finally, higher levels of CXCL13 were detected in the blood and BM samples of MM patients in comparison with healthy individuals.ConclusionsAltogether, our findings suggest that bidirectional interactions of MΦ with MM tumor cells result in M2 MΦ polarization, CXCL13 induction, and subsequent OC activation, enhancing their ability to support bone resorption and MM progression. CXCL13 may thus serve as a potential novel target in MM.

021 CXCL13-producing peripheral T helper cells as potential mediators of photosensitivity in dermatomyositis

Dermatomyositis (DM) is a rare autoimmune disease that causes photosensitivity, disfiguring rash, and pruritus. Type I interferons (IFN-Is) are expressed in lesional (L) skin of DM, suggesting their role in disease pathogenesis. Using suction blistering on both L and non-lesional (NL) skin of treatment-naïve patients with DM followed by single-cell RNA sequencing (scRNA-seq) and flow cytometry, we found a distinct population of T cells expressing high levels of CXCL13, only in L DM. Their immunophenotype (CD4+/PD-1hi/CXCR5-) was characteristic of T peripheral helper (Tph) cells, a new subset of T cells recently described to drive autoimmunity in rheumatoid arthritis via CXCL13 mediated recruitment of B cells to synovium. However, consistent with previous reports, we did not find any B cells infiltrating L DM skin. Intriguingly, we observed high expression of CXCR5 on a subset of CD8+ T cells in both DM blood and L skin, suggesting CXCL13 promotes recruitment of cytotoxic CD8+ T cells to the inflamed skin. ELISA on the interstitial skin fluid confirmed higher levels of CXCL13 in L DM than NL and healthy (p<0.001), and immunohistochemistry highlighted CXCL13 staining colocalizing within perivascular CD4+ T cells. Using gene set enrichment analysis in our scRNA-seq data, we identified a robust IFN-I signature in Tph cells in DM skin. Further, we found that CD4+ T cells from DM blood displayed a significantly higher CXCL13 expression in response to IFNA than those from healthy subjects in vitro (p<0.01). Moreover, we observed that keratinocytes (KCs) isolated from L DM exhibit an enhanced IFNA expression in response to UVB than healthy in vitro, indicating an exaggerated IFN-I response to UVB in DM KCs induces differentiation of CXCL13-producing Tph cells in the skin, leading to the recruitment of circulating cytotoxic CD8+ T cells. These findings suggest a novel role for the IFN-I/CXCL13 axis in DM pathogenesis and its potential contribution to photosensitivity.

Abstract 1265: Identification of a predictive circulating immunological signature of response to immune checkpoint inhibitors in non-small cell lung cancer

Abstract In non-small cell lung cancer (NSCLC), response to immune checkpoint blockade (ICB) is associated with programmed cell death ligand 1 expression that is induced by interferon-γ-produced by tumor-infiltrating CD8+ T cells. However, not all tumors with a PD-L1 expression and/or CD8+ T cell infiltrate respond to ICB, and some tumors without any PD-L1 expression respond to ICB. Moreover, little is known about all the mechanisms governing ICB resistance in NSCLC. The objective of the study was to investigate a circulating immunological signature (cytokines, chemokines and immune checkpoints) which could be predictive of resistance to ICB in patients with advanced NSCLC. We performed a multiplexed analysis on 23 TruCulture® (in vitro T cells activation system) and 41 plasma samples using the Luminex® platform (Bio-Techne, MN USA). We investigated the relationship between the levels at baseline of 30 circulating analytes and the response to ICB of advanced NSCLC patients. Through the TruCulture® samples analysis, we identified two types of responders depending on T cell functionality. The responders with a functional T cell activation had lower levels of neutrophil associated analytes (CXCL5/6; p-value&amp;lt;0.05) than non-responders. They had lower levels of IL-13 and higher levers of TNFα, respectively Th2 and Th1/CD8+/NK associated analytes. All responders had lower levels of CCL17 and higher levels of CXCL10 in plasma samples, respectively M2/N2 and M1/N1 associated analytes. This study highlighted two distinct profiles of ICB responders. The first group has a functional T cell response with a favorable orientation to antitumor cytotoxic action (Th1/CD8+) and few cytokines associated with neutrophils. The second group has a poor functional T cell response, whereas their favorable response to ICB is potentially linked to the activation of the innate immune response. The plasma study highlighted the potential role of polarization of the innate response in the context of the response to ICB for all patients. Citation Format: Wassila Khatir, Olivier Humbert, Jaap Neels, Léa Berland, Jonathan Benzaquen, Fabian Andrés Gallardo Rivera, Maryline Allegra, Myriam Salah, Virginie Tanga, Olivier Bordone, Julien Fayada, Virginie Lespinet-Fabre, Elodie Long-Mira, Sandra Lassalle, Patrick Brest, Valérie Vouret, Charlotte Maniel, Jacques Boutros, Simon Heeke, Véronique Hofman, Charles-Hugo Marquette, Paul Hofman, Marius Ilie. Identification of a predictive circulating immunological signature of response to immune checkpoint inhibitors in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1265.

Plasma cytokines during pregnancy provide insight into the risk of diabetes in the gestational diabetes risk group.

ABSTRACTAims/IntroductionGestational diabetes (GDM) is characterized by low‐grade systemic inflammation, which manifests as changes in the levels of cytokines in the blood. We aimed to investigate plasma immune mediators during gestational weeks 23–28 in 213 women at risk for GDM, and to find associations between GDM and its complications.Materials and MethodsWe quantified the levels of adipokines: adiponectin, leptin, plasminogen activator inhibitor‐1 and resistin; chemokines: C‐C motif chemokine ligand 2 (CCL2), CCL4, C‐X‐C motif chemokine ligand 8 (CXCL8) and CXCL10; and cytokines: granulocyte‐macrophage colony‐stimulating factor, interferon‐γ, interleukin (IL)‐1β, soluble (s)IL‐1RI, IL‐2, sIL‐2Ra, IL‐4, IL‐5, IL‐6, IL‐7, IL‐10, IL‐12(p70), IL‐13, IL‐15, IL‐17A, IL‐17F, IL‐21, IL‐22, IL‐23, IL‐27, transforming growth factor (TGF)‐β1, TGF‐β2, TGF‐β3, tumor necrosis factor‐α and soluble tumor necrosis factor receptor 2 using the Milliplex®MAP Magnetic Bead assay on Luminex®200™, and compared the results with clinical data from pregnancy and post‐partum follow up.ResultsLower levels of adiponectin and higher levels of CCL2 (Wilcoxon test, P = 3.4E‐03 and P = 0.03, respectively) were found in women with GDM. IL‐27 levels were associated with lower odds of GDM (adjusted logistic regression 0.90, P = 2.4E‐03), and showed a risk association with glutamic acid decarboxylase autoantibody positivity (adjusted odds ratio 1.13, P = 2.8E‐03). Similarly, higher IL‐22 levels increased the odds of glutamic acid decarboxylase autoantibody positivity (adjusted odds ratio 4.23, P = 0.04). TGF‐β1 was associated with post‐partum fasting glucose levels, and CCL4 with post‐partum C‐peptide levels (linear regression, P = 0.04 and P = 0.01, respectively). Women who developed pregnancy complications had higher levels of CXCL10 and CCL4 (linear regression, P = 7.0E‐04 and P = 0.01, respectively).ConclusionsPlasma adiponectin and CCL2 concentrations distinguish women with GDM. IL‐27 and IL‐22 levels might select women with an autoimmune reaction, whereas increased TGF‐β1 and CCL4 are associated with post‐partum glucose and insulin metabolism.