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Nikolaos Davanos,1 George Panos,2 Charalambos A Gogos,2 Athanasia Mouzaki1 1Division of Hematology, Department of Internal Medicine, Faculty of Medicine, 2Division of Infectious Diseases, Department of Internal Medicine, University Hospital, University of Patras, Patras, Greece Background: The rapid replication rate of HIV-1, coupled with a high mutation rate and recombination, is the underlying force driving its genetic diversity. In the infected individual, a population of highly related but nonidentical strains exists. At the population level, multiple subtypes often cocirculate, leading to the generation of intersubtype recombinant forms. As a result, the geographic distribution of subtypes and recombinant forms is complex and uneven. Genetic subtyping of HIV-1 isolates has been shown to be helpful for understanding the genetic evolution, the worldwide spread of the virus, and the evaluation of drug resistance. Materials and methods: We determined the genetic heterogeneity of HIV-1 group M in southwestern Greece. Protease and partial reverse-transcriptase sequences were generated from 150 HIV-1-infected individuals attending the Division of Infectious Diseases of Patras University Hospital, Greece, from 2006 to 2012, and analyzed using online subtyping tools and phylogenetic methods. Results: The majority of the infected individuals were male (77%). HIV-1 subtype A1 was responsible for 51.3% of infections, followed by subtypes B (34%), G (4%), F1 (2%), and the circulating recombinant forms 02_AG (2.7%), 14_BG (1.3%), 35_AD (1.3%), and 01_AE (0.7%). Additionally, we identified three cases with a recombinant B/CRF02_AG strain (2%) and one with a recombinant G/GRF_AG strain. Sexual transmission was responsible for 96.3% of cases. Heterosexual transmission was responsible for 70.2% of subtype-A1 infections, whereas subtype B was transmitted by men who have sex with men in 75.5% of cases. Protease substitutions I13V, E35D, M36I, R57K, H69K, and L89M, which serve as drug-resistance support mutations in subtype B, were present in the majority of subtype-A1 sequences of the population. Conclusion: HIV-1 infection in southwestern Greece is sexually transmitted and highly heterogeneous. Subtype A1 has surpassed subtype B, and is the most prevalent strain. In the population studied, subtype A1 exhibited certain polymorphisms in the protease region, which may serve as drug-resistance support mutations in subtype B. Keywords: HIV-1 infection, transmission, subtype, sequence, genetic signatures, epidemiology

Radiation therapy (RT) is an essential component in the therapeutic treatment of patients with localized prostate cancer (LPCa). Besides its local effects, ionizing radiation has been linked to mechanisms leading to systemic immune activation. The present study explored the effect of RT on the T‑cell receptor variable β (TCR Vβ) chain repertoire of peripheral blood T cells in patients with LPCa. High‑throughput TCR Vβ sequencing was performed on 20 blood samples collected from patients with LPCa at baseline and 3 months post‑RT. The diversity index was altered, as were TCR Vβ clonal evenness and convergence before and post‑RT; however, these findings were not significant. Notably, marked changes in the frequencies among the top 10 TCR Vβ clonotypes were detected and some patients developed new clonotypes of high abundance. These data provided initial evidence that RT in patients with LPCa may induce systemic immune changes, which could be exploited by future therapies for improved clinical results.

COVID-19 incidence and case fatality rates (CFR) differ among ethnicities, stimulating efforts to pinpoint genetic factors that could explain these phenomena. In this regard, the multiallelic apolipoprotein E (APOE) gene has recently been interrogated in the UK biobank cohort, demonstrating associations of the APOE ε4/ε4 genotype with COVID-19 severity and mortality. The frequency of the ε4 allele and thus the distribution of APOE ε4/ε4 genotype may differ among populations. We have assessed APOE genotypes in 1638 Greek individuals, based on haplotypes derived from SNP rs7412 and rs429358 and found reduced frequency of ε4/ε4 compared to the British cohort. Herein we discuss this finding in relation to CFR and hypothesize on the potential mechanisms linking APOE ε4/ε4 to severe COVID-19. We postulate that the metabolic deregulation ensued by APOE4, manifested by elevated cholesterol and oxidized lipoprotein levels, may be central to heightened pneumocyte susceptibility to infection and to exaggerated lung inflammation associated with the ε4/ε4 genotype. We also discuss putative dietary and pharmacological approaches for the prevention and management of COVID-19 in APOE ε4/ε4 individuals., (Copyright © 2021. Published by Elsevier B.V.)

Background: Cell-free fetal DNA in maternal plasma presents interest as it can possibly serve as a pregnancy associated biomarker. For its quantitation, we investigate the use of fluorescent polymerase chain reaction (PCR) amplification of short tandem repeats (STRs) in pregnancies irrespective of sex., Methods: Artificially chimeric DNA samples were prepared so as to simulate cell-free fetal DNA in maternal plasma at different proportions. The samples were tested with fluorescent PCR amplification of informative STRs and the percentage of the population simulating fetal DNA was plotted against a relative ratio of the alleles detected in each sample. The graphs were used for the quantitation of cell-free fetal DNA in 50 maternal plasma samples., Results: Detection of at least one paternally inherited fetal STR was possible in 46/50 pregnancies leading to the estimation of the relative percentage of cell-free fetal DNA. Four pregnancies failed to reveal any fetal allele which may reflect undetectable levels (<1%) of fetal DNA. Among pregnancies fetal DNA ranged from 0 to 20% (mean value of 7%)., Conclusion: Our system can readily estimate the relative levels of cell-free fetal DNA in maternal circulation, normal gestations of either sex and can be exploited for estimating possible variations of this analyte between normal and pathological pregnancies., (Copyright © 2011 Elsevier B.V. All rights reserved.)