Slower immune system aging in women versus men in the Japanese population

R e v i e w S e R i e S : A u t o i m m u n i t y 2 1 8 8jci.org Volume 125 Number 6 June 2015expression of IFN1 genes is controlled directly by sex hormones. On the other hand, sex hormones do affect expression of some of the PRRs (see below) and in this way might indirectly affect IFN1 levels. Thus, the abundance of IFN1s in lupus patients might be caused by female sex hormone-induced increases in PRR levels, which in turn increase production of IFN1s. One of the genes that controls expression of IFN1s is IFN regulatory factor 5 (IRF5). IRF5 has also been identified as a significant risk factor for lupus susceptibility (37,38). Expression of IRF5 in mice has been reported to be sex dependent (39). As demonstrated by Shen and colleagues (39), C57BL/6, NZB, Nba2, NZB/NZW F1, and NZM mouse strains express significantly higher levels of Irf5 mRNA in female than in male lymphocytes. Additionally, splenocytes from lupus-prone mice were shown to express higher levels of Irf5 mRNA compared with cells from the C57BL/6 strain, which is not prone to lupus. This group further demonstrated that Irf5 expression can be upregulated in vitro upon estrogen treatment, suggesting a potential mechanism for sex-biased expression of the gene and consequent overproduction of IFN1s (39).Absence of IFN-γ signaling protects NZB/NZW F1 mice against lupus-like disease (40). Expression of the IFNG gene, on the other hand, is regulated directly by estrogens (41)(42)(43)(44)(45). This finding suggests a positive feedback loop between the IFNs and estrogens, since activation of IFN1 or IFN-γ signaling upregulates the expression of ERα (46). Estrogen, in turn, promotes IFN-γ production by various lymphocytes. In addition, Panchanathan et al. demonstrated synergistic involvement of ERα and IFN signaling in activating the transcription of both IFN and estrogen-responsive target genes (46).Once produced, IFNs have many effects on the immune system that contribute to the sex bias of autoimmunity. For example, IFN1s increase class 1 MHC expression on cells, and IFN-γ induces class II MHC and changes the nature of the proteasome, thereby affecting the nature and quantity of self-peptides presented to T cells. Other examples are described below. Other immune-associated genes affected by sex hormonesMany genes with products that affect the immune system are controlled by sex hormones. As far as innate immunity is concerned, estrogens induce the expression of intracellular but not surface TLRs in both male and female PBMCs (23). Because intracellular TLRs have been shown to affect the development of autoimmunity (47-51), it is possible that the hormonal effect of the expression of intracellular TLRs contributes to female-biased autoimmunity.Unc-93 homolog B1 (UNC93B1) is an endoplasmic reticulum (ER) transmembrane protein that is essential for trafficking the TLRs that are expressed intracellularly (TLR3, TLR7, TLR8, TLR9, and probably other TLRs) from the ER to endosomes (52-54). UNC93B1 regulates the activity of these TLRs by mediating localization t...

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The interstitial pneumonia (IP) associated with myeloperoxidase anti-neutrophil cytoplasmic autoantibody (MPO-ANCA) showed characteristic histology dominated by usual IP pattern. We showed a 94-year-old woman, whose prognosis was poor by severity of IP by MPO-ANCA associated vasculitis. The median age at diagnosis of IP by MPO-ANCA associated vasculitis was over 60 years, with a male predominance. Most patients died related to respiratory insufficiency. Our case would be the oldest patient in IP by MPO-ANCA associated vasculitis in the literature.