Comparison of T Lymphocyte Subsets and Natural Killer Lymphocytes in Moderate Versus Severe COVID-19 Patients.

Severe respiratory involvement that follows a process of immune dysregulation and intense cytokine production remains to be the most dreaded complication of Coronavirus Disease-2019 (COVID-19) infection. The aim of this study was to analyze T lymphocyte subsets and natural killer (NK) lymphocytes in moderate and severe cases of COVID-19 infection and assess their significance in disease severity and prognosis. Twenty moderate cases and 20 severe cases of COVID-19 were studied and compared regarding blood picture, biochemical markers, T lymphocyte population subsets, and NK lymphocytes, which were determined by flow cytometric analysis. On analyzing the flow cytometric data of T lymphocyte cells and their subsets and NK cells in two groups of COVID-19 infection (one group moderate and the other severe cases), some immature NK lymphocyte relative and absolute counts were higher in the severe patients with worse outcome and death, while some mature NK lymphocyte relative and absolute counts were depressed in both groups. Also, interleukin (IL)-6 was significantly higher in severe cases when compared to moderate cases, and there was a positive significant correlation between immature NK lymphocyte relative and absolute counts and IL-6. There was no statistically significant difference between T lymphocyte subsets (T helper and T cytotoxic) with disease severity or outcome. Some immature NK lymphocyte subsets contribute to the widespread inflammatory response that complicates severe cases of COVID-19; therapeutic approaches directed to enhancing NK maturation or drugs that block NK cell inhibitory receptors have a potential role in controlling COVID-19 induced cytokine storm.

Expression of microRNA-223 and microRNA-146b in serum and liver tissue of mice infected with Schistosoma mansoni.

MicroRNAs (miRNAs) play regulatory roles in several diseases. In schistosomiasis, the main pathological changes are caused by the granulomatous reaction induced by egg deposition. We aimed to study the changes in host miRNA-223 and miRNA-146b expression in relation to egg deposition and development of hepatic pathology in murine schistosomiasis mansoni. Blood and liver tissue samples were collected from non-infected mice (group I), S. mansoni-infected mice at the 4th, 8th, and 12th weeks post-infection (p.i.) (groups II-IV), and 4 weeks after praziquantel treatment (group V). The collected samples were processed for RNA extraction, reverse transcription, and real-time PCR analysis of miRNA-223 and miRNA-146b. miRNAs' relative expression was estimated by the ΔΔCt method. Liver tissue samples were examined for egg count estimation and histopathological evaluation. Results revealed that miRNA-223 was significantly downregulated in liver tissues 8 and 12 weeks p.i., whereas miRNA-146b expression increased gradually with the progression of infection with a significantly higher level at week 12 p.i. compared to week 4 p.i. Serum expression levels nearly followed the same pattern as the tissue levels. The dysregulated expression of miRNAs correlated with liver egg counts and was more obvious with the demonstration of chronic granulomas, fibrous transformation, and distorted hepatic architecture 12 weeks p.i. Restoration of normal expression levels was observed 4 weeks after treatment. Collectively, these findings provide new insights for in-depth understanding of host-parasite interaction in schistosomiasis and pave a new way for monitoring the progress of hepatic pathology before and after treatment.

Herpes zoster might be an indicator for latent COVID 19 infection.

Various cutaneous manifestations have been observed in patients with COVID-19 infection. Herpes zoster is a viral skin disease caused by varicella zoster that remains dormant in the dorsal root ganglia of cutaneous nerves following a primary chicken pox infection. In this report, we describe two cases COVID infection who first presented with herpes zoster. We are here by suggesting that the clinical presentation of HZ at the time of the current pandemic even in patients giving mild or no suggestive history of upper respiratory symptoms should be considered as an alarming sign for a recent subclinical SARS CoV2 infection.

Herpes zoster may be a marker for COVID-19 infection during pregnancy.

Varicella-zoster virus infection causes 2 distinct forms of disease: varicella (commonly known as chickenpox) and herpes zoster (HZ)(commonly known as shingles). Primary varicella-zoster virus infection results in the diffuse vesicular rash that is characteristic of chickenpox. Following primary infection, varicella-zoster virus remains dormant in the dorsal root ganglia. This latent phase usually lasts for several decades before reactivation occurs. Varicella-zoster virus reactivation normally presents as HZ in middle-aged adults. A number of cutaneous skin manifestations have appeared in relation to the newly diagnosed coronavirus disease 2019 (COVID-19) pandemic and continue to emerge every day. We report a case of HZ complication in a COVID-19-positive woman who was 27 weeks pregnant.