Elevated IgA and IL-10 levels in very-early-onset inflammatory bowel disease secondary to IL-10 receptor deficiency.

OBJECTIVE: To report two patients with very-early-onset inflammatory bowel disease (VEOIBD) secondary to interleukin-10 receptor (IL-10R) mutations, explore immunophenotyping data and plasma cytokine profile on these cases compared to healthy controls, and describe the phenotype of IL-10/IL-10R mutations based on a literature review. CASE DESCRIPTION: We report on two female infants referred to our tertiary center at the age of ten months, with severe colonic and perianal disease, as well as significant malnutrition, who had shown limited response to usual inflammatory bowel disease (IBD) therapy agents. In the first case, whole-exome sequencing (WES) revealed a homozygous (c.537G>A/p.T179T) mutation in exon 4 of the IL-10RA gene, while in the second patient, compound heterozygosity was identified, also in the IL-10RA gene (chr11:117.859.199 variant A>G/p.Tyr57Cys and chr11: 117.860.335 variant G>T/p.Val123Leu). Both patients underwent hematopoietic cell transplantation (HCT). Immunological work-up of these patients revealed increased IL-10 plasma levels and increased IgA. COMMENTS: Our case reports disclose novel findings on plasma cytokine profile in IL-10R deficiency, and we describe the severe phenotype of IL-10/IL-10R deficiency that should be recognized by physicians.

Erythema Nodosum Leprosum Neutrophil Subset Expressing IL-10R1 Transmigrates into Skin Lesions and Responds to IL-10.

Erythema nodosum leprosum (ENL) is an inflammatory complication in leprosy. Yet, the involvement of ENL neutrophils in the inflammatory response against Mycobacterium leprae remains poorly explored. Our primary aim was to investigate the utility of the surface expression of neutrophil IL-10R1 as an ENL biomarker and, secondarily, to evaluate whether leprosy or healthy M. leprae-stimulated neutrophils produce cytokines and are able to respond to IL-10. We, in this study, describe a subpopulation of circulating neutrophils of ENL patients that exclusively expressed IL-10R1, providing evidence that IL-10R1+ neutrophils are present in ENL lesions. It was also found that ENL neutrophils, but not those of nonreactional leprosy controls, were able to secret detectable levels of TNF ex vivo and the addition of IL-10 blocked TNF release. It was likewise observed that M. leprae-stimulated, healthy neutrophils expressed IL-10R1 in vitro, and ENL-linked cytokines were released by M. leprae-cultured neutrophils in vitro. Moreover, consistent with the presence of a fully functional IL-10R, the addition of IL-10 prevented the release of M. leprae-induced cytokines. Most importantly, dead M. leprae revealed its superior capacity to induce CCL4 and IL-8 in primary neutrophils over live Mycobacterium, suggesting that M. leprae may hamper the inflammatory machinery as an immune escape mechanism.

Expression of the interleukin-10 signaling pathway genes in individuals with Down syndrome and periodontitis.

BACKGROUND: Individuals with Down syndrome (DS) have a higher prevalence and severity of periodontal disease, which cannot be explained by poor oral hygiene alone and is related to changes in the immune response. The aim of this study is to evaluate whether DS was associated with differential modulation of expression of genes associated with proinflammatory and anti-inflammatory responses in periodontal disease. METHODS: A total of 51 individuals were evaluated: 19 individuals with DS and periodontal disease (group 1), 20 euploid individuals with periodontal disease (group 2; positive control), and 12 euploid individuals without periodontal disease (group 3; negative control). Clinical periodontal evaluation and gingival biopsies were performed. Quantitative reverse transcription-polymerase chain reaction was used to determine expression levels of interleukin-10 (IL-10), the receptors IL-10RA and IL-10RB, intracellular adhesion molecule 1 (ICAM-1), interferon-γ-inducible protein 10 (IP-10), and the signaling intermediates Janus kinase 1, signal transducer and activator of transcription 3 (STAT-3), and suppressor of cytokine signaling 3 (SOCS-3). RESULTS: Expression of IL10, SOCS3, IP10, and ICAM1 mRNA in DS patients was significantly lower compared to euploid individuals with periodontal disease, whereas IL-10RB and STAT-3 mRNA levels were higher in individuals with DS. CONCLUSION: Reduced expression of IL-10 coupled with a possible increase of STAT3 activation (increase of STAT3 and reduction of SOCS3 mRNA) indicates an important modulation of the immune response, with attenuation of anti-inflammatory and increase of proinflammatory mediators. This modulation may be related to the increased prevalence and severity of periodontitis in individuals with DS.