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Background/aims: Glial fibrillary acidic protein (GFAP) is an established indicator of retinal stress; its expression in retinal astrocytes and Müller cells has been demonstrated to be modulated by cytokines and retinal pathology, including age related macular degeneration (AMD). This study aims to quantify the modulation of GFAP expression in retinas with drusen and atrophic AMD versus normal age matched controls. Methods: Following a histopathological survey, 17 donor retinas were classified into four groups: drusen (n=5), geographic atrophy (GA) (n=6), aged normal (n=3), and young normal (n=3). Paramacular cryosections were immunolabelled with GFAP antibody, examined by confocal microscopy, and quantified by NIH digital image analysis. Groups were matched for potential confounding factors including age, sex, and postmortem delay. Results: A significant increase in GFAP immunolabelling of macroglia was noted in aged normal compared with young normal retinas (p<0.04). Upregulation of GFAP immunoreactivity involving astrocytes was observed in drusen retinas compared with control retinas (p<0.03). GFAP was also upregulated in retinas with GA compared with controls (p<0.05) and in retinas with GA compared with drusen (p<0.04), both involving Müller cells. Discrete regions of GFAP upregulation in Müller cells were associated with drusen formation. In GA specimens atrophied retinal pigment epithelium (RPE) was substituted by GFAP immunoreactive Müller cell processes (gliosis). Conclusion:This study provides a quantitative assessment of GFAP modulation in ageing and AMD affected retinas. Morphological observations were consistent with quantitative analyses indicating differential modulation of GFAP immunoreactivity in inner and outer retina. Upmodulation of GFAP in inner retina and astroglial processes was predominantly associated with drusen, while in outer retina Müller glia upmodulation of GFAP was associated with disruption of the RPE and blood-retinal barrier.

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There was no consistent pattern of association found between ARM and circulating inflammatory markers or hemostatic factors in this population-based case-control study.

Purpose Deficiency of adenosine deaminase type 2 (ADA2) (DADA2) is a rare inborn error of immunity caused by deleterious biallelic mutations in ADA2. Clinical manifestations are diverse, ranging from severe vasculopathy with lacunar strokes to immunodeficiency with viral infections, hypogammaglobulinemia and bone marrow failure. Limited data are available on the phenotype and function of leukocytes from DADA2 patients. The aim of this study was to perform in-depth immunophenotyping and functional analysis of the impact of DADA2 on human lymphocytes. Methods In-depth immunophenotyping and functional analyses were performed on ten patients with confirmed DADA2 and compared to heterozygous carriers of pathogenic ADA2 mutations and normal healthy controls. Results The median age of the patients was 10 years (mean 20.7 years, range 1–44 years). Four out of ten patients were on treatment with steroids and/or etanercept or other immunosuppressives. We confirmed a defect in terminal B cell differentiation in DADA2 and reveal a block in B cell development in the bone marrow at the pro-B to pre-B cell stage. We also show impaired differentiation of CD4+ and CD8+ memory T cells, accelerated exhaustion/senescence, and impaired survival and granzyme production by ADA2 deficient CD8+ T cells. Unconventional T cells (i.e. iNKT, MAIT, Vδ2+ γδT) were diminished whereas pro-inflammatory monocytes and CD56bright immature NK cells were increased. Expression of the IFN-induced lectin SIGLEC1 was increased on all monocyte subsets in DADA2 patients compared to healthy donors. Interestingly, the phenotype and function of lymphocytes from healthy heterozygous carriers were often intermediate to that of healthy donors and ADA2-deficient patients. Conclusion Extended immunophenotyping in DADA2 patients shows a complex immunophenotype. Our findings provide insight into the cellular mechanisms underlying some of the complex and heterogenous clinical features of DADA2. More research is needed to design targeted therapy to prevent viral infections in these patients with excessive inflammation as the overarching phenotype.

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ObjectiveFamilial pituitary tumour syndromes (FPTS) account for 5% of pituitary adenomas. Multi-gene analysis via next-generation sequencing (NGS) may unveil greater prevalence and inform clinical care. We aimed to identify germline variants in selected patients with pituitary adenomas using a targeted NGS panel.DesignWe undertook a nationwide cross-sectional study of patients with pituitary adenomas with onset ≤40 years of age and/or other personal/family history of endocrine neoplasia. A custom NGS panel was performed on germline DNA to interrogate eight FPTS genes. Genome data were analysed via a custom bioinformatic pipeline, and validation was performed by Sanger sequencing. Multiplex ligation-dependent probe amplification (MLPA) was performed in cases with heightened suspicion forMEN1,CDKN1BandAIPmutations. The main outcomes were frequency and pathogenicity of rare variants inAIP,CDKN1B,MEN1,PRKAR1A,SDHA,SDHB,SDHCandSDHD.ResultsForty-four patients with pituitary tumours, 14 of whom had a personal history of other endocrine tumours and/or a family history of pituitary or other endocrine tumours, were referred from endocrine tertiary-referral centres across Australia. Eleven patients (25%) had a rare variant across the eight FPTS genes tested:AIP(p.A299V, p.R106C, p.F269F, p.R304X, p.K156K, p.R271W),MEN1(p.R176Q),SDHB(p.A2V, p.S8S),SDHC(p.E110Q) andSDHD(p.G12S), with two patients harbouring dual variants. Variants were classified as pathogenic or of uncertain significance in 9/44 patients (20%). No deletions/duplications were identified inMEN1,CDKN1BorAIP.ConclusionsA high yield of rare variants in genes implicated in FPTS can be found in selected patients using an NGS panel. It may also identify individuals harbouring more than one rare variant.

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