Immune system adaptation during gender-affirming testosterone treatment.

Infectious, inflammatory and autoimmune conditions present differently in males and females. SARS-CoV-2 infection in naive males is associated with increased risk of death, whereas females are at increased risk of long COVID1, similar to observations in other infections2. Females respond more strongly to vaccines, and adverse reactions are more frequent3, like most autoimmune diseases4. Immunological sex differences stem from genetic, hormonal and behavioural factors5 but their relative importance is only partially understood6-8. In individuals assigned female sex at birth and undergoing gender-affirming testosterone therapy (trans men), hormone concentrations change markedly but the immunological consequences are poorly understood. Here we performed longitudinal systems-level analyses in 23 trans men and found that testosterone modulates a cross-regulated axis between type-I interferon and tumour necrosis factor. This is mediated by functional attenuation of type-I interferon responses in both plasmacytoid dendritic cells and monocytes. Conversely, testosterone potentiates monocyte responses leading to increased tumour necrosis factor, interleukin-6 and interleukin-15 production and downstream activation of nuclear factor kappa B-regulated genes and potentiation of interferon-γ responses, primarily in natural killer cells. These findings in trans men are corroborated by sex-divergent responses in public datasets and illustrate the dynamic regulation of human immunity by sex hormones, with implications for the health of individuals undergoing hormone therapy and our understanding of sex-divergent immune responses in cisgender individuals.

SARS-CoV-2 Antiviral Prescribing Gaps Among Nonhospitalized High-Risk Adults.

Within a multistate clinical cohort, SARS-CoV-2 antiviral prescribing patterns were evaluated from April 2022-June 2023 among nonhospitalized patients with SARS-CoV-2 with risk factors for severe COVID-19. Among 3247 adults, only 31.9% were prescribed an antiviral agent (87.6% nirmatrelvir/ritonavir, 11.9% molnupiravir, 0.5% remdesivir), highlighting the need to identify and address treatment barriers.

Positive predictive value highlights four novel candidates for actionable genetic screening from analysis of 220,000 clinicogenomic records.

PURPOSE: To identify conditions that are candidates for population genetic screening based on population prevalence, penetrance of rare variants, and actionability. METHODS: We analyzed exome and medical record data from >220,000 participants across two large population health cohorts with different demographics. We performed a gene-based collapsing analysis of rare variants to identify genes significantly associated with disease status. RESULTS: We identify 74 statistically significant gene-disease associations across 27 genes. Seven of these conditions have a positive predictive value (PPV) of at least 30% in both cohorts. Three are already used in population screening programs (BRCA1, BRCA2, LDLR), and we also identify four new candidates for population screening: GCK with diabetes mellitus, HBB with ß-thalassemia minor and intermedia, PKD1 with cystic kidney disease, and MIP with cataracts. Importantly, the associations are actionable in that early genetic screening of each of these conditions is expected to improve outcomes. CONCLUSION: We identify seven genetic conditions where rare variation appears appropriate to assess in population screening, four of which are not yet used in screening programs. The addition of GCK, HBB, PKD1, and MIP rare variants into genetic screening programs would reach an additional 0.21% of participants with actionable disease risk, depending on the population.

Is Adrenal Insufficiency a Rare Disease?

Adrenal insufficiency (AI) is a potentially life-threatening condition and it is of utmost importance to identify and adequately manage affected individuals. Diagnosis is often delayed, probably partly because diseases of the adrenal or pituitary region that cause primary AI (PAI) or central AI are relatively rare conditions. However, iatrogenic AI, i.e. the physiological downregulation of the hypothalamic-pituitary-adrenal axis and adrenal atrophy caused by glucocorticoid treatment for different inflammatory conditions is likely to be considerably more common. The type of glucocorticoid, dose and duration of treatment are factors to consider when trying to predict the risk of developing symptoms of AI. However, the considerable individual variation in the sensitivity for developing iatrogenic AI impedes prediction. In industrialized countries, autoimmune adrenalitis accounts for the majority of cases of PAI. Among children, genetic conditions - in particular congenital adrenal hyperplasia - need to be considered. Important risk groups for central AI are patients with tumours in the hypothalamic-pituitary region, moderate-to-severe traumatic head injury and patients who receive cranial radiotherapy or cytotoxic T-lymphocyte antigen 4 blockade treatment. Structured endocrine follow-up is essential in these groups. Health workers need to be attentive to these potentially fatal conditions and at-risk populations should be carefully informed about symptoms and signs of AI.

Plasmacytoid DC promote priming of autoimmune Th17 cells and EAE.

EAE, an animal model for MS, is a Th17 and Th1-cell-mediated autoimmune disease, but the mechanisms leading to priming of encephalitogenic T cells in autoimmune neuroinflammation are poorly understood. To investigate the role of plasmacytoid DC (pDC) in the initiation of autoimmune Th17- and Th1-cell responses and EAE, we depleted pDC with anti-pDC Ag-1 (anti-PDCA1) mAb prior to immunization of C57BL/6 mice with myelin oligodendrocyte glycoprotein (MOG). pDC-depleted mice developed less severe clinical and histopathological signs of EAE than control mice, which demonstrates a promoting role for pDC in the initiation of EAE. The levels of type I IFN were much lower in the sera from anti-PDCA1-treated mice. However, neutralization of type I IFN ameliorated the early phase of EAE but did not alter the severity of disease. Thus, only a minor part of the EAE-promoting effect of pDC appears to be mediated by IFN-alpha/beta secretion. The numbers of MOG-specific Th17 cells, but not Th1 cells, were lower in spleen from anti-PDCA1-treated mice compared with controls. In contrast, pDC depletion a week after MOG immunization resulted in more severe clinical signs of EAE. In conclusion, we demonstrate that pDC promote initiation of MOG-induced Th17-cell responses and EAE.

Impaired autoimmune T helper 17 cell responses following DNA vaccination against rat experimental autoimmune encephalomyelitis.

BACKGROUND: We have previously shown that vaccination with DNA encoding the encephalitogenic peptide myelin oligodendrocyte glycoprotein (MOG)(91-108) (pMOG) suppresses MOG(91-108)-induced rat Experimental Autoimmune Encephalomyelitis (EAE), a model for human Multiple Sclerosis (MS). The suppressive effect of pMOG is dependent on inclusion of CpG DNA in the plasmid backbone and is associated with early induction of Interferon (IFN)-beta. PRINCIPAL FINDINGS: In this study we examined the mechanisms underlying pMOG-induced protection. We found that in the DNA vaccinated cohort proinflammatory Interleukin (IL)-17 and IL-21 responses were dramatically reduced compared to in the control group, but that the expression of Foxp3 and Tumor Growth Factor (TGF)-beta1, which are associated with regulatory T cells, was not enhanced. Moreover, genes associated with Type I IFNs were upregulated. To delineate the role of IFN-beta in the protective mechanism we employed short interfering RNA (siRNA) to IFN-beta in the DNA vaccine. SiRNA to IFN-beta completely abrogated the protective effects of the vaccine, demonstrating that a local early elaboration of IFN-beta is important for EAE protection. IL-17 responses comparable to those in control rats developed in rats injected with the IFN-beta-silencing DNA vaccine. CONCLUSIONS: We herein demonstrate that DNA vaccination protects from proinflammatory Th17 cell responses during induction of EAE. The mechanism involves IFN-beta as IL-17 responses are rescued by silencing of IFN-beta during DNA vaccination.

Duplication of FGF3, FGF4, FGF19 and ORAOV1 causes hair ridge and predisposition to dermoid sinus in Ridgeback dogs.

The dorsal hair ridge in Rhodesian and Thai Ridgeback dogs is caused by a dominant mutation that also predisposes to the congenital developmental disorder dermoid sinus. Here we show that the causative mutation is a 133-kb duplication involving three fibroblast growth factor (FGF) genes. FGFs play a crucial role in development, suggesting that the ridge and dermoid sinus are caused by dysregulation of one or more of the three FGF genes during development.