Chronic mucocutaneous candidiasis and connective tissue disorder in humans with impaired JNK1-dependent responses to IL-17A/F and TGF-β

Genetic etiologies of chronic mucocutaneous candidiasis (CMC) disrupt human IL-17A/F-dependent immunity at mucosal surfaces, whereas those of connective tissue disorders (CTDs) often impair the TGF-β-dependent homeostasis of connective tissues. The signaling pathways involved are incompletely understood. We report a three-generation family with an autosomal dominant (AD) combination of CMC and a previously undescribed form of CTD that clinically overlaps with Ehlers-Danlos syndrome (EDS). The patients are heterozygous for a private splice-site variant of MAPK8, the gene encoding c-Jun N-terminal kinase 1 (JNK1), a component of the MAPK signaling pathway. This variant is loss-of-expression and loss-of-function in the patients' fibroblasts, which display AD JNK1 deficiency by haploinsufficiency. These cells have impaired, but not abolished, responses to IL-17A and IL-17F. Moreover, the development of the patients' TH17 cells was impaired ex vivo and in vitro, probably due to the involvement of JNK1 in the TGF-β-responsive pathway and further accounting for the patients' CMC. Consistently, the patients' fibroblasts displayed impaired JNK1- and c-Jun/ATF-2-dependent induction of key extracellular matrix (ECM) components and regulators, but not of EDS-causing gene products, in response to TGF-β. Furthermore, they displayed a transcriptional pattern in response to TGF-β different from that of fibroblasts from patients with Loeys-Dietz syndrome caused by mutations of TGFBR2 or SMAD3, further accounting for the patients' complex and unusual CTD phenotype. This experiment of nature indicates that the integrity of the human JNK1-dependent MAPK signaling pathway is essential for IL-17A- and IL-17F-dependent mucocutaneous immunity to Candida and for the TGF-β-dependent homeostasis of connective tissues

CAR T‐cell therapy induces a high rate of prolonged remission in relapsed primary CNS lymphoma: Real‐life results of the LOC network

International audienceThe prognosis of relapsed primary central nervous system lymphoma (PCNSL) remains dismal. CAR T‐cells are a major contributor to systemic lymphomas, but their use in PCNSL is limited. From the LOC network database, we retrospectively selected PCNSL who had leukapheresis for CAR‐T cells from the third line of treatment, and, as controls, PCNSL treated with any treatment, at least in the third line and considered not eligible for ASCT. Twenty‐seven patients (median age: 68, median of three previous lines, including ASCT in 14/27) had leukapheresis, of whom 25 received CAR T‐cells (tisa‐cel: N = 16, axi‐cel: N = 9) between 2020 and 2023. All but one received a bridging therapy. The median follow‐up after leukapheresis was 20.8 months. The best response after CAR‐T cells was complete response in 16 patients (64%). One‐year progression‐free survival from leukapheresis was 43% with a plateau afterward. One‐year relapse‐free survival was 79% for patients in complete or partial response at CAR T‐cell infusion. The median overall survival was 21.2 months. Twenty‐three patients experienced a cytokine release syndrome and 17/25 patients (68%) a neurotoxicity (five grade ≥3). The efficacy endpoints were significantly better in the CAR T‐cell group than in the control group (N = 247) (median PFS: 3 months; median OS: 4.7 months; p < 0.001). This series represents the largest cohort of PCNSL treated with CAR T‐cells reported worldwide. CAR T‐cells are effective in relapsed PCNSL, with a high rate of long‐term remission and a reassuring tolerance profile. The results seem clearly superior to those usually observed in this setting

A variety of Alu-mediated copy number variations can underlie IL-12Rβ1 deficiency

Inborn errors of IFN-gamma immunity underlie Mendelian susceptibility to mycobacterial disease (MSMD). Autosomal recessive complete IL-12R beta 1 deficiency is the most frequent genetic etiology of MSMD. Only two of the 84 known mutations are copy number variations (CNVs), identified in two of the 213 IL-12R beta 1-deficient patients and two of the 164 kindreds reported. These two CNVs are large deletions found in the heterozygous or homozygous state. We searched for novel families with IL-12R beta 1 deficiency due to CNVs. We studied six MSMD patients from five unrelated kindreds displaying adverse reactions to BCG vaccination. Three of the patients also presented systemic salmonellosis, two had mucocutaneous candidiasis, and one had disseminated histoplasmosis. We searched for CNVs and other variations by IL12RB1-targeted next-generation sequencing (NGS). We identified six new IL-12R beta 1-deficient patients with a complete loss of IL-12R beta 1 expression on phytohemagglutinin-activated T cells and/or EBV-transformed B cells. The cells of these patients did not respond to IL-12 and IL-23. Five different CNVs encompassing IL12RB1 (four deletions and one duplication) were identified in these patients by NGS coverage analysis, either in the homozygous state (n = 1) or in trans (n = 4) with a single-nucleotide variation (n = 3) or a small indel (n = 1). Seven of the nine mutations are novel. Interestingly, four of the five CNVs were predicted to be driven by nearby Alu elements, as well as the two previously reported large deletions. The IL12RB1 locus is actually enriched in Alu elements (44.7%), when compared with the rest of the genome (10.5%). The IL12RB1 locus is Alu-enriched and therefore prone to rearrangements at various positions. CNVs should be considered in the genetic diagnosis of IL-12R beta 1 deficiency

Inherited CARD9 Deficiency: Invasive Disease Caused by Ascomycete Fungi in Previously Healthy Children and Adults

Abstract: Autosomal recessive CARD9 deficiency underlies life-threatening, invasive fungal infections in otherwise healthy individuals normally resistant to other infectious agents. In less than 10 years, 58 patients from 39 kindreds have been reported in 14 countries from four continents. The patients are homozygous (n = 49; 31 kindreds) or compound heterozygous (n = 9; 8 kindreds) for 22 different CARD9 mutations. Six mutations are recurrent, probably due to founder effects. Paradoxically, none of the mutant alleles has been experimentally demonstrated to be loss-of-function. CARD9 is expressed principally in myeloid cells, downstream from C-type lectin receptors that can recognize fungal components. Patients with CARD9 deficiency present impaired cytokine and chemokine production by macrophages, dendritic cells, and peripheral blood mononuclear cells and defective killing of some fungi by neutrophils in vitro. Neutrophil recruitment to sites of infection is impaired in vivo. The proportion of Th17 cells is low in most, but not all, patients tested. Up to 52 patients suffering from invasive fungal diseases (IFD) have been reported, with ages at onset of 3.5 to 52 years. Twenty of these patients also displayed superficial fungal infections. Six patients had only mucocutaneous candidiasis or superficial dermatophytosis at their last follow-up visit, at the age of 19 to 50 years. Remarkably, for 50 of the 52 patients with IFD, a single fungus was involved; only two patients had IFDs due to two different fungi. IFD recurred in 44 of 45 patients who responded to treatment, and a different fungal infection occurred in the remaining patient. Ten patients died from IFD, between the ages of 12 and 39 years, whereas another patient died at the age of 91 years, from an unrelated cause. At the most recent scheduled follow-up visit, 81% of the patients were still alive and aged from 6.5 to 75 years. Strikingly, all the causal fungi belonged to the phylum Ascomycota: commensal Candida and saprophytic Trychophyton, Aspergillus, Phialophora, Exophiala, Corynesprora, Aureobasidium, and Ochroconis. Human CARD9 is essential for protective systemic immunity to a subset of fungi from this phylum but seems to be otherwise redundant. Previously healthy patients with unexplained invasive fungal infection, at any age, should be tested for inherited CARD9 deficiency. Key Points: • Inherited CARD9 deficiency (OMIMSCOPUS: re.jinfo:eu-repo/semantics/publishe

L’expérimentation animale reste indispensable (OPINION)

Trop fréquemment, l’expérimentation animale est présentée comme une pratique archaïque. Elle a bien changé. Et 100 % des patients traités le sont grâce aux concepts et techniques développés grâce à elle