Manish Butte

Int Immunopharmacol. 2023 Jun 21;121:110488. doi: 10.1016/j.intimp.2023.110488. Online ahead of print.

ABSTRACT

BACKGROUND: Sepsis is the major cause of death in intensive care units. We previously found that intermedin (IMD), a calcitonin family peptide, can protect against sepsis by dynamically repairing vascular endothelial junctions and can ameliorate the inflammatory response by inhibiting the infiltration of macrophages in peripheral tissues. The effects of IMD on inflammatory and immune responses indicate that IMD may play a role in immunity. However, whether IMD affects immune cell development, differentiation and response to infection remains unclear.

METHODS: IMD-knockout (Adm2^-/-) mice were generated in our previous work. Wild-type and IMD-KO mice were subjected to sham or cecal ligation and puncture (CLP) surgery, and bone marrow cells were obtained for RNA sequencing (RNA-Seq) analysis. The RNA-Seq results were verified by real-time RT-PCR. The effect of IMD KO or IMD rescue on the septic mice was explored using mild and severe infection models induced by CLP surgery at different levels of severity, and the survival outcomes were analyzed using Kaplan-Meier curves and the log-rank test. The mechanism underlying the effects of IMD in T/B cell proliferation and differentiation were investigated by PCR, Western blot (WB), and cell proliferation assays and flow cytometry analysis.

RESULTS: RNA-Seq showed that IMD-KO mice exhibited a primary immunosuppression phenotype characterized by a marked decrease in the expression of T- and B-cell function-related genes. This immunosuppression made the IMD-KO mice vulnerable to pathogenic invasion, and even mild infection killed nearly half of the IMD-KO mice. Supplementation with the IMD peptide restored the expression of T/B-cell-related genes and significantly reduced the mortality rate of the IMD-KO mice. IMD is likely to directly promote T- and B-cell proliferation through ERK1/2 phosphorylation, stimulate T-cell differentiation via Ilr7/Rag1/2-controled T cell receptor (TCR) recombination, and activate B cells via Pax5, a transcription factor that activates at least 170 genes needed for B-cell functions.

CONCLUSION: Together with previous findings, our results indicate that IMD may play a protective role in sepsis via three mechanisms: protecting the vascular endothelium, reducing the inflammatory response, and activating T/B-cell proliferation and differentiation. Our study may provide the first identification of IMD as a calcitonin peptide that plays an important role in the adaptive immune response by activating T/B cells and provides translational opportunities for the design of immunotherapies for sepsis and other diseases associated with primary immunodeficiency.

PMID:37352568 | DOI:10.1016/j.intimp.2023.110488

Nat Commun. 2023 Jun 22;14(1):3728. doi: 10.1038/s41467-023-39295-7.

ABSTRACT

Loss of NBEAL2 function leads to grey platelet syndrome (GPS), a bleeding disorder characterized by macro-thrombocytopenia and α-granule-deficient platelets. A proportion of patients with GPS develop autoimmunity through an unknown mechanism, which might be related to the proteins NBEAL2 interacts with, specifically in immune cells. Here we show a comprehensive interactome of NBEAL2 in primary T cells, based on mass spectrometry identification of altogether 74 protein association partners. These include LRBA, a member of the same BEACH domain family as NBEAL2, recessive mutations of which cause autoimmunity and lymphocytic infiltration through defective CTLA-4 trafficking. Investigating the potential association between NBEAL2 and CTLA-4 signalling suggested by the mass spectrometry results, we confirm by co-immunoprecipitation that CTLA-4 and NBEAL2 interact with each other. Interestingly, NBEAL2 deficiency leads to low CTLA-4 expression in patient-derived effector T cells, while their regulatory T cells appear unaffected. Knocking-down NBEAL2 in healthy primary T cells recapitulates the low CTLA-4 expression observed in the T cells of GPS patients. Our results thus show that NBEAL2 is involved in the regulation of CTLA-4 expression in conventional T cells and provide a rationale for considering CTLA-4-immunoglobulin therapy in patients with GPS and autoimmune disease.

PMID:37349339 | DOI:10.1038/s41467-023-39295-7

Nat Commun. 2023 Jun 22;14(1):3708. doi: 10.1038/s41467-023-39272-0.

ABSTRACT

We describe the first cases of germline biallelic null mutations in ARPC5, part of the Arp2/3 actin nucleator complex, in two unrelated patients presenting with recurrent and severe infections, early-onset autoimmunity, inflammation, and dysmorphisms. This defect compromises multiple cell lineages and functions, and when protein expression is reestablished in-vitro, the Arp2/3 complex conformation and functions are rescued. As part of the pathophysiological evaluation, we also show that interleukin (IL)-6 signaling is distinctively impacted in this syndrome. Disruption of IL-6 classical but not trans-signaling highlights their differential roles in the disease and offers perspectives for therapeutic molecular targets.

PMID:37349293 | DOI:10.1038/s41467-023-39272-0

PLoS Pathog. 2023 Jun 22;19(6):e1011455. doi: 10.1371/journal.ppat.1011455. Online ahead of print.

ABSTRACT

XIAP is an endogenous inhibitor of cell death and inactivating mutations of XIAP are responsible for X-linked lymphoproliferative disease (XLP-2) and primary immunodeficiency, but the mechanism(s) behind these contradictory outcomes have been unclear. We report that during infection of macrophages and dendritic cells with various intracellular bacteria, XIAP restricts cell death and secretion of IL-1β but promotes increased activation of NFκB and JNK which results in elevated secretion of IL-6 and IL-10. Poor secretion of IL-6 by Xiap-deficient antigen presenting cells leads to poor expansion of recently activated CD8 T cells during the priming phase of the response. On the other hand, Xiap-deficient CD8 T cells displayed increased proliferation and effector function during the priming phase but underwent enhanced contraction subsequently. Xiap-deficient CD8 T cells underwent skewed differentiation towards short lived effectors which resulted in poor generation of memory. Consequently Xiap-deficient CD8 T cells failed to provide effective control of bacterial infection during re-challenge. These results reveal the temporal impact of XIAP in promoting the fitness of activated CD8 T cells through cell extrinsic and intrinsic mechanisms and provide a mechanistic explanation of the phenotype observed in XLP-2 patients.

PMID:37347786 | DOI:10.1371/journal.ppat.1011455

N Engl J Med. 2023 Jun 21. doi: 10.1056/NEJMoa2210054. Online ahead of print.

ABSTRACT

BACKGROUND: Increasing evidence links genetic defects affecting actin-regulatory proteins to diseases with severe autoimmunity and autoinflammation, yet the underlying molecular mechanisms are poorly understood. Dedicator of cytokinesis 11 (DOCK11) activates the small Rho guanosine triphosphatase (GTPase) cell division cycle 42 (CDC42), a central regulator of actin cytoskeleton dynamics. The role of DOCK11 in human immune-cell function and disease remains unknown.

METHODS: We conducted genetic, immunologic, and molecular assays in four patients from four unrelated families who presented with infections, early-onset severe immune dysregulation, normocytic anemia of variable severity associated with anisopoikilocytosis, and developmental delay. Functional assays were performed in patient-derived cells, as well as in mouse and zebrafish models.

RESULTS: We identified rare, X-linked germline mutations in DOCK11 in the patients, leading to a loss of protein expression in two patients and impaired CDC42 activation in all four patients. Patient-derived T cells did not form filopodia and showed abnormal migration. In addition, the patient-derived T cells, as well as the T cells from Dock11-knockout mice, showed overt activation and production of proinflammatory cytokines that were associated with an increased degree of nuclear translocation of nuclear factor of activated T cell 1 (NFATc1). Anemia and aberrant erythrocyte morphologic features were recapitulated in a newly generated dock11-knockout zebrafish model, and anemia was amenable to rescue on ectopic expression of constitutively active CDC42.

CONCLUSIONS: Germline hemizygous loss-of-function mutations affecting the actin regulator DOCK11 were shown to cause a previously unknown inborn error of hematopoiesis and immunity characterized by severe immune dysregulation and systemic inflammation, recurrent infections, and anemia. (Funded by the European Research Council and others.).

PMID:37342957 | DOI:10.1056/NEJMoa2210054

Vaccine. 2023 Jun 17:S0264-410X(23)00715-6. doi: 10.1016/j.vaccine.2023.06.040. Online ahead of print.

ABSTRACT

The patient is an otherwise healthy two-month-old boy who received the recommended vaccinations for his age group, which included the rotavirus pentavalent vaccine (RV5; RotaTeq) at his two-month well child visit. Three days later, he developed prolonged non-bloody diarrhea and was found to have persistently positive rotavirus antigen in his stool. Subsequent workup revealed mild defects in his functional T-cell immunocompetence. Genetic testing was obtained through the Invitae panel and was negative for hereditary forms of primary immunodeficiencies. The rotavirus antigen was found to have cleared from his stool around four months after receiving the RV5. Unfortunately, the source of the rotavirus infection was unable to be determined. The caregivers had misconceptions about the vaccine and the child’s immune system function which led to refusal of any further vaccinations. Healthcare providers should strive to develop honest and respectful relationships with parents to have thoughtful dialogues regarding vaccine safety and efficacy.

PMID:37336660 | DOI:10.1016/j.vaccine.2023.06.040

Immunology. 2023 Jun 19. doi: 10.1111/imm.13675. Online ahead of print.

ABSTRACT

It is widely understood that cancer is a significant cause of morbidity and mortality worldwide. Despite numerous available treatments, prognosis for many remains poor, thus, the development of novel therapies remains essential. Given the incredible success of many immunotherapies in this field, the important contribution of the immune system to the control, and elimination, of malignancy is clear. While many immunotherapies target higher-order pathways, for example, through promoting T-cell activation via immune checkpoint blockade, the potential to target specific immunological pathways is largely not well researched. Precisely understanding how immunity can be tailored to respond to specific challenges is an exciting idea with great potential, and may trigger the development of new therapies for cancer. Inborn Errors of Immunity (IEI) are a group of rare congenital disorders caused by gene mutations that result in immune dysregulation. This heterogeneous group, spanning widespread, multisystem immunopathology to specific immune cell defects, primarily manifest in immunodeficiency symptoms. Thus, these patients are particularly susceptible to life-threatening infection, autoimmunity and malignancy, making IEI an especially complex group of diseases. While precise mechanisms of IEI-induced malignancy have not yet been fully elucidated, analysis of these conditions can highlight the importance of particular genes, and downstream immune responses, in carcinogenesis and may help inform mechanisms which can be utilised in novel immunotherapies. In this review, we examine the links between IEIs and cancer, establishing potential connections between immune dysfunction and malignancy and suggesting roles for specific immunological mechanisms involved in preventing carcinogenesis, thus, guiding essential future research focused on cancer immunotherapy and providing valuable insight into the workings of the immune system in both health and disease.

PMID:37335539 | DOI:10.1111/imm.13675

Front Immunol. 2023 Jun 2;14:1226814. doi: 10.3389/fimmu.2023.1226814. eCollection 2023.

ABSTRACT

[This corrects the article DOI: 10.3389/fimmu.2022.1011646.].

PMID:37334381 | PMC:PMC10273397 | DOI:10.3389/fimmu.2023.1226814

Front Med (Lausanne). 2023 Jun 2;10:1189361. doi: 10.3389/fmed.2023.1189361. eCollection 2023.

ABSTRACT

BACKGROUND: Triple-negative breast cancer (TNBC) is a common carcinoma in women, and the prognosis of TNBC is the worst. Using data from The Cancer Genome Atlas (TCGA) database, we analyzed the functional roles of cytokine-related genes in TNBC.

METHODS: The clinical and transcriptome data of TNBC patients were downloaded from TCGA database. A systematical analyses of the data from TCGA database were conducted to screen the prognostic genes and identify the main cytokine-related pathways related to TNBC.

RESULTS: We identified 499 prognostic genes in TNBC patients from TCGA database and the cytokine-related pathways closely related to TNBC. TCGA-TNBC patients were divided into the high-risk cluster (C1) group and the low-risk cluster (C2) group based on the cytokine-related genes. The C1 group patients exhibited tumor metastasis and an advanced tumor stage. The functional analysis revealed that the upregulated differentially expressed genes (DEGs) in the C1 group were mainly associated with the extracellular matrix (ECM)-receptor interaction, stem cell proliferation, focal adhesion, and cyclic adenosine monophosphate (cAMP) signaling pathway, while the downregulated DEGs in the C1 group were mainly associated with cytokine and cytokine receptors, T-helper 17 (Th17) cell differentiation, and primary immunodeficiency. The immune activity of C1 group was lower than that of C2 group, and the identified half-maximal inhibitory concentration scores of 3 chemotherapy drugs (i.e., doxorubicin, methotrexate, and paclitaxel) were lower in C2 group than C1 group. More importantly, we constructed a novel prognostic signature and identified the following 8 genes: CCL25, CXCL13, IL12RB2, IL21, TNFRSF13C, TNFRSF8, CCL7 and GDF5.

CONCLUSION: The status of the cytokine-related pathway was closely related to tumor classification and immune activity in the TNBC patients. The gene signature of the cytokine-related genes showed an good performance in predicting the prognosis of TNBC patients, and could predict the prognosis of TNBC patients.

PMID:37332770 | PMC:PMC10275569 | DOI:10.3389/fmed.2023.1189361

J Clin Immunol. 2023 Jun 16. doi: 10.1007/s10875-023-01532-5. Online ahead of print.

ABSTRACT

Purine nucleoside phosphorylase deficient severe combined immunodeficiency (PNP SCID) is one of the rare autosomal recessive primary immunodeficiency disease, and the data on epidemiology and outcome are limited. We report the successful management of a child with PNP SCID and present a systematic literature review of published case reports, case series, and cohort studies on PNP SCID listed in PubMed, Web of Science, and Scopus from 1975 until March 2022. Forty-one articles were included from the 2432 articles retrieved and included 100 PNP SCID patients worldwide. Most patients presented with recurrent infections, hypogammaglobulinaemia, autoimmune manifestations, and neurological deficits. There were six reported cases of associated malignancies, mainly lymphomas. Twenty-two patients had undergone allogeneic hematopoietic stem cell transplantation with full donor chimerism seen mainly in those receiving matched sibling donors and/or conditioning chemotherapy before the transplant. This research provides a contemporary, comprehensive overview on clinical manifestations, epidemiology, genotype mutations, and transplant outcome of PNP SCID. These data highlight the importance of screening for PNP SCID in cases presented with recurrent infections, hypogammaglobulinaemia, and neurological deficits.

PMID:37328647 | DOI:10.1007/s10875-023-01532-5