The amounts of Akkermansia muciniphila and Faecalibacterium prausnitzii in gut microbiota are reduced in patients with allergic diseases compared to healthy controls. We aimed to quantify levels of A. muciniphila and F. prausnitzii amounts using real-time quantitative PCR (qPCR) in the gut microbiota of children with allergic asthma and in healthy controls. In total, 92 children between the ages of three and eight who were diagnosed with asthma and 88 healthy children were included in the study and bacterial DNA was isolated from the stool samples using the stool DNA isolation Kit. qPCR assays were studied with the microbial DNA qPCR Kit for A. muciniphila and microbial DNA qPCR Kit for F. prausnitzii. Both bacterial species showed a reduction in the patient group compared to healthy controls. A. muciniphila and F. prausnitzii were found to be 5.45±0.004, 6.74±0.01 and 5.71±0.002, 7.28±0.009 in the stool samples of the asthma and healthy control groups, respectively. F. prausnitzii and A. muciniphila may have induced anti-inflammatory cytokine IL-10 and prevented the secretion of pro-inflammatory cytokines like IL-12. These findings suggest that A. muciniphila and F. prausnitzii may suppress inflammation through its secreted metabolites.

Complete IFN-γ receptor ligand-binding chain (IFNγR1) deficiency is a life-threatening autosomal recessive immune disorder. Affected children invariably die of mycobacterial infection, unless bone marrow transplantation is undertaken. Pathogenic IFNGR1 mutations identified to date include nonsense and splice mutations and frameshift deletions and insertions. All result in a premature stop codon upstream from the segment encoding the transmembrane domain, precluding cell surface expression of the receptors. We report herein two sporadic and two familial cases of a novel form of complete IFNγR1 deficiency in which normal numbers of receptors are detected at the cell surface. Two in-frame deletions and two missense IFNGR1 mutations were identified in the segment encoding the extracellular ligand-binding domain of the receptor. Eight independent IFNγR1-specific mAb’s, including seven blocking antibodies, gave recognition patterns that differed between patients, suggesting that different epitopes were altered by the mutations. No specific binding of ¹²⁵I–IFN-γ to cells was observed in any patient, however, and the cells failed to respond to IFN-γ. The mutations therefore cause complete IFNγR1 deficiency by disrupting the IFN-γ–binding site without affecting surface expression. The detection of surface IFNγR1 molecules by specific antibodies, including blocking antibodies, does not exclude a diagnosis of complete IFNγR1 deficiency.

Beşer ÖF, et al. Allergy Asthma Immunol Res. 2014 Jan;6(1):33-38. http://dx.doi.org/10.4168/aair.2014.6.1.33