The coronavirus disease 2019 (COVID-19) pandemic remains a significant public health threat globally with significant socio-economic impacts. People living with human immunodeficiency virus (HIV) (PLWH) have a high risk of severe outcomes of COVID-19 due to immunosuppression. Clinical manifestation of COVID-19 in HIV patients largely remains unclear. We carried out a pilot study to investigate the clinical laboratory data and circulating cytokines in PLWH infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in Tatarstan, Russia. Serum samples were collected from three groups: PLWH with COVID-19 (PLWH/COVID-19), COVID-19-only, and uninfected controls. We found an increased risk of severe COVID-19 in PLWH/COVID-19 patients compared to COVID-19-only. Four fatal cases were in PLWH/COVID-19, while there was no fatality in COVID-19-only. Pro-inflammatory cytokines, such as IL-5, IL-6, IL-9, and IL-15, were elevated in PLWH/COVID-19 compered to COVID-19-only. These preliminary findings highlight the potential for more severe COVID-19 in PLWH/COVID-19 where pro-inflammatory cytokines could play pathogenic role.

Мультиэпитопные вакцины представляют собой перспективный инструмент профилактики вирусных инфекций, способный индуцировать комплексный гуморальный и клеточный иммунный ответ. В статье рассмотрены современные подходы к проектированию in silico химерных вакцинных конструкций: критерии отбора эпитопов, методы прогнозирования перспективных Т- и В-клеточных эпитопов, выбор линкеров и адъювантов, структурное моделирование, молекулярный докинг и симуляция иммунного ответа. Интеграция иммунноинформатических методов и молекулярного моделирования существенно ускоряет разработку вакцинных кандидатов и повышает точность прогнозирования до начала экспериментальной проверки.

(1) Background: Hemorrhagic fever with renal syndrome (HFRS) remains a prevalent zoonosis in Eurasia. Orthohantavirus puumalaense (PUUV), carried by bank voles (Myodes glareolus), is the principal zoonotic pathogen of HFRS in this region. Despite ongoing efforts to develop effective drugs and vaccines against PUUV, this challenge remains. (2) Aim: In this study, we aimed to express a large quantity of the PUUV recombinant N (rN) protein using E. coli. We also sought to develop a protocol for extracting the rN protein from pellets, solubilizing, and refolding it to restore its native form. This protocol is crucial for producing a large quantity of rN protein to develop vaccines and diagnostic tools for HFRS. (3) Methods; PUUV S segment open reading frame (ORF) coding for N protein was synthesized and cloned into the plasmid vector pET-28 (A+). The ORF was transformed, expressed and induced in BL21(DE3) pLysS E. coli strain. Subsequently, rN protein was purified using immobilized metal affinity and ion chromatography. Immune reactivity of rN protein was tested by employing in house and commercial VektoHanta-IgG kit ELISA methods (both in vitro and in vivo). (4) Results: The best conditions for scaling up the expression of the PUUV rN protein were an incubation temperature of 20 °C during a 20 h incubation period, followed by induction with 0.5 mM IPTG. The most significant protein yield was achieved when the pellets were incubated in denaturing buffer with 8M urea. The highest yield of refolded proteins was attained using non-denaturing buffer (50 mM Tris-HCl) supplemented with arginine. A final 50 μL of PUUV rN protein solution with a concentration of 7 mg/mL was recovered from 1 L of culture. The rN protein elicited an antibody response in vivo and reacted with serum taken from patients with HFRS by ELISA in vitro. (5) Conclusion: Therefore, the orthohantavirus N protein’s ability to elicit immune response in vivo suggests that it can be used to develop vaccines against PUUV after conducting in vitro and in vivo studies to ascertain neutralising antibodies.

Hemorrhagic fever with renal syndrome (HFRS) remains one of the leading natural focal infections in Russia, characterized by pronounced clinical variability. Clinical manifestations of HFRS, in particular, may be determined by single nucleotide polymorphisms (SNPs) in early immune response genes in patients. We determined the allele and genotype frequencies of SNPs in the CASP1 (rs580253) and IL‑6 (rs1800795) genes. CASP1 encodes caspase‑1, an enzyme that is the product of the activated inflammasome, while IL‑6 encodes interleukin‑6, a cytokine of the acute immune response. It was found that the genotype frequencies in the control group conformed to the Hardy–Weinberg law, whereas in HFRS patients a statistically significant deviation from the expected equilibrium was detected, which suggests the existence of correlations between the genotypes of the studied SNPs and the clinical manifestations of the disease.