Evaluation of SARS-CoV-2 Specific IgG Antibodies in Individuals Vaccinated with Covaxin (BBV152): An Independent Assessment.

Post vaccination with Covaxin (BBV152), Serum from healthcare professionals of Microbiology Department at apex tertiary referral hospital of India were tested for SARS-CoV-2 specific IgG antibodies. 70% individuals at 14-30 days, 63.1% individuals at 30-60 days but only 36.8% individuals at 60-90 days after second dose of vaccine had detectable SARS-CoV-2 spike protein specific IgG antibodies. However, 80% individuals at 14-30 days, 89.4% individuals at 30-60 days while 94.7% individuals at 60-90 days after second dose of vaccine had detectable SARS-CoV-2 whole cell antigen specific IgG antibodies. Males were lacking SARS-CoV-2 spike protein specific IgG antibodies in higher proportion than females and had lower index wherever detected. Age and co-morbidities were non-significant factors for post vaccination IgG response but not in breakthrough infection. 8.3% individuals developed mild COVID-19 symptoms post 14-90 days of second dose and none had severe COVID-19. SARS-CoV-2 spike protein specific IgG antibodies induced by Covaxin are drastically reduced in 60-90 days among fully vaccinated individuals which could be a potential risk for breakthrough SARS-CoV-2 infection, if not severe COVID-19. It may be essential to have additional antigenic stimulations/boosters for continued protection.

HIV testing & diagnosis in 2020 at the apex tertiary referral hospital of India: impact of COVID-19 pandemic.

Timely HIV testing and diagnosis are necessary to prevent the development of AIDS and interrupt its transmission in society. We collected the data on HIV testing and diagnosis in 2020 and compared it with preceding years to examine how COVID-19 pandemic-related restrictions impacted HIV services. The number of people who underwent HIV testing at the apex tertiary referral hospital of India in 2020 reduced by 57% compared to 2019 or the average/year during 2019-2016. Hence, the diagnosis of new HIV infections decreased by 52% compared to 2019 and 54% compared to the average/year during 2019-2016. Provider-initiated testing and diagnosis were more affected than client-initiated. There was a non-significant change in the rate of HIV detection among tested individuals. The male testing saw a more notable drop than female testing. HIV testing between ≥50 years and ≤14 years was more affected than other age groups. The transmission via regular partner/spouse increased, whereas it decreased via heterosexual commercial sex workers.

Effect of Withania somnifer on CD38 expression on CD8+ T lymphocytes among patients of HIV infection.

CD38 on CD8 + T cells is considered a reliable marker of HIV disease progression. Withania somnifer, a traditional ayurvedic medicine, has Th1 immunomodulatory properties. PBMCs from 38 HIV patients were exposed to Withania somnifer root extract at standardized concentration. An overall decline in the percentage of CD38 expressing CD8 + T lymphocytes was observed, though the statistical significance was varied with different categories of HIV patients. Withania somnifer could have promising impact on HIV disease and therefore warrants a further study on larger parameters.

An update on host immunity correlates and prospects of re-infection in COVID-19.

Reinfection with SARS-CoV-2 is not frequent yet the incidence rate of it is increasing globally owing to the slow emergence of drift variants that pose a perpetual threat to vaccination strategies and have a greater propensity for disease reoccurrence. Long-term protection against SARS-CoV-2 reinfection relies on the induction of the innate as well as the adaptive immune response endowed with immune memory. However, a multitude of factors including the selection pressure, the waning immunity against SARS-CoV-2 over the first year after infection possibly favors evolution of more infectious immune escape variants, amplifying the risk of reinfection. Additionally, the correlates of immune protection, the novel SARS-CoV-2 variants of concern (VOC), the durability of the adaptive and mucosal immunity remain major challenges for the development of therapeutic and prophylactic interventions. Interestingly, a recent body of evidence indicated that the gastrointestinal (GI) tract is another important target organ for SARS-CoV-2 besides the respiratory system, potentially increasing the likelihood of reinfection by impacting the microbiome and the immune response via the gut-lung axis. In this review, we summarized the latest development in SARS-CoV-2 reinfection, and explored the untapped potential of trained immunity. We also highlighted the immune memory kinetics of the humoral and cell-mediated immune response, genetic drift of the emerging viral variants, and discussed the current challenges in vaccine development. Understanding the dynamics and the quality of immune response by unlocking the power of the innate, humoral and cell-mediated immunity during SARS-CoV-2 reinfection would open newer avenues for drug discovery and vaccine designs.

Immunological factors associated with discordant virological response postcombination antiretroviral therapy in pediatric human immunodeficiency virus infection.

OBJECTIVES: Evaluation of immunological factors responsible for discordant virological responses postcombination antiretroviral therapy (cART) in human immunodeficiency virus (HIV)-positive children aged <5 years. MATERIALS AND METHODS: Immunological profiling of enrolled 30 HIV-positive children was done at enrollment, 6 and 12 months. Flow cytometric analysis was performed for enumeration of counts and percentage of CD4+, CD8+, and CD19+ cells; expression of CD19, CD86, PD-1, CD3, CD8 and CD28 on lymphocytes was evaluated using whole blood staining technique with monoclonal antibodies. HIV-1 viral load was quantified using a real-time polymerase chain reaction. Serum levels of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin (IgM), and interleukin (IL)-7 were quantitated using quantitative enzyme-linked immunosorbent assay kits. The HIV-infected children were categorized into virological responders (VRs; HIV-1 plasma viral load <47 copies/mL) and virological nonresponders (VNRs; HIV-1 plasma viral load >1000 copies/mL) following 1-year cART. RESULTS: The frequency of CD28+ CTLs cells was higher (P < 0.0001), and the frequency of CD28-CTLs cells was lower (P < 0.0001) in VRs than VNRs. CD28+ and CD28-CTLs cells correlated with HIV-1 plasma viremia (r = -0.4695, P = 0.01; r = 0.40, P = 0.03, respectively). VRs had higher CD19 percentage (P = 0.04) and count (P = 0.01) than VNRs. CD19+ B cells in the VRs had lower expression of CD86 (P = 0.03) and PD-1 (P = 0.002) than VNRs. VR had lower levels of serum IgG (P = 0.03), IgM (P = 0.04), and IL-7 (P = 0.01) than VNRs. CONCLUSIONS: High baseline B-cell counts, lower serum IgG, IgM, IL-7 levels, lower activation and exhaustion of B cells, and higher frequency of CD28+ CTLs are associated with positive virological response, whereas elevated CD28-CTLs are associated with the poor virological outcomes in HIV-infected children.

The Evolution of Regulatory Elements in the Emerging Promoter-Variant Strains of HIV-1 Subtype C.

In a multicentric, observational, investigator-blinded, and longitudinal clinical study of 764 ART-naïve subjects, we identified nine different promoter variant strains of HIV-1 subtype C (HIV-1C) emerging in the Indian population, with some of these variants being reported for the first time. Unlike several previous studies, our work here focuses on the evolving viral regulatory elements, not the coding sequences. The emerging viral strains contain additional copies of the existing transcription factor binding sites (TFBS), including TCF-1α/LEF-1, RBEIII, AP-1, and NF-κB, created by sequence duplication. The additional TFBS are genetically diverse and may blur the distinction between the modulatory region of the promoter and the viral enhancer. In a follow-up analysis, we found trends, but no significant associations between any specific variant promoter and prognostic markers, probably because the emerging viral strains might not have established mono infections yet. Illumina sequencing of four clinical samples containing a coinfection indicated the domination of one strain over the other and establishing a stable ratio with the second strain at the follow-up time points. Since a single promoter regulates viral gene expression and constitutes the master regulatory circuit with Tat, the acquisition of additional and variant copies of the TFBS may significantly impact viral latency and latent reservoir characteristics. Further studies are urgently warranted to understand how the diverse TFBS profiles of the viral promoter may modulate the characteristics of the latent reservoir, especially following the initiation of antiretroviral therapy.

ECG changes in a case of attempted partial hanging.

This is a case of attempted partial hanging that behaved like a cerebrovascular accident. The serial electrocardiograms (ECGs) showed the characteristic ST and T-wave changes, QT prolongation and U waves later reverting to normal over a period of one month.

A simplified touch tape preparation from tube cultures for microscopic examination of filamentous fungi.

Cellophane touch tape preparation provides reproducible results in minimal time when compared to tease mount and slide culture techniques for the identification of fungi from culture plates, but it is difficult to perform from tube cultures. Here, we describe an easy to perform touch tape preparation method that provided a better result from fungal tube culture.