Landscape of B Cell Receptor Repertoires in COVID-19 Patients Revealed Through CDR3 Sequencing of Immunoglobulin Heavy and Light Chains.

The outbreak and persistence of coronavirus disease 2019 (COVID-19) threaten human health. B cells play a vital role in fighting the infections caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite many studies on the immune responses in COVID-19 patients, it is still unclear how B cell receptor (BCR) constituents, including immunoglobulin heavy (IGHs) and light chains (IGLs), respond to SARS-CoV-2 in patients with varying symptoms. In this study, we conducted complementarity-determining region 3 (CDR3) sequencing of BCR IGHs and IGLs from the peripheral blood of COVID-19 patients and healthy donors. The results showed significantly reduced clonal diversity, more expanded clones, and longer CDR3 lengths of IGH and IGL in COVID-19 patients than those in healthy individuals. The IGLs had a much higher percentage of VJ skew usage (47.83% IGLV and 42.86% IGLJ were significantly regulated) than the IGHs (12.09% IGHV and 0% IGHJ) between the healthy individuals and patients, which indicated the importance of BCR light chains. Furthermore, we found a largely expanded IGLV3-25 gene cluster mostly pairing with IGLJ1 and ILGJ2 in COVID-19 patients and a newly identified upregulated IGLJ1 gene and IGLJ2+IGLV13-21 recombination, both of which are potential sources of SARS-CoV-2-targeting antibodies. Our findings on specific immune B-cell signatures associated with COVID-19 have clinical implications for vaccine and biomarker development for disease diagnosis.

Clinical characteristics and predictors of delayed discharge among children with SARS­CoV­2 Omicron variant infection.

The present study investigated the epidemiology and clinical characteristics of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant and determined the risk factors for delayed discharge or release from isolation for pediatric patients in Quanzhou, China in 2022. There were 145, 254 and 23 patients in the asymptomatic, mildly symptomatic and moderately symptomatic categories, respectively. The proportion of pediatric patients in the moderately symptomatic category increased with increasing age. No child aged <1 year and 9.02% of patients aged 13-18 years were in the moderately symptomatic category. The proportion of patients with asymptomatic infection did not differ significantly by vaccination status. The median days until the first negative conversion of viral RNA was 11 days, and the median hospitalization duration was 16 days. Most symptoms appeared in the upper respiratory tract. Notably, ~33.23% of patients showed elevated aspartate aminotransferase levels. C-reactive protein and interleukin-6 (IL-6) levels, and lymphocyte counts were consistently lower in asymptomatic patients than those in in symptomatic patients. Adjusted logistic regression analyses indicated that IL-6 levels and time to the first negative conversion of viral RNA were independent risk factors for delayed discharge. The area under the curve of the regression model for predicting delayed discharge was 0.760. In conclusion, these results could facilitate the formulation of global epidemic prevention policies for pediatric patients.

Epidemiological and clinical features of SARS-CoV-2 Omicron variant infection in Quanzhou, Fujian province: a retrospective study.

Epidemiological and clinical data of patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant (BA.2) admitted to three designated hospitals in Quanzhou City, Fujian Province, China, were collected and analyzed. Overall, 2,541 patients infected with BA.2, comprising 1,060 asymptomatic, 1,287 mild, and 194 moderate infections, were enrolled. The percentage of moderate infections was higher in patients aged ≥ 60 years than in those aged < 18 years and 18-59 years. The median hospitalization duration was 17 days. Among the 2,541 patients, 43.52% had a clear history of close contact. The vaccination rate was 87.92%, and the percentage of asymptomatic infections was higher in vaccinated than in unvaccinated patients. Moreover, patients with underlying diseases, including hypertension and diabetes mellitus, had more moderate infections than those without underlying diseases. The three most common clinical manifestations were fever, dry cough, and sore throat. The albumin-to-globulin (A/G) ratio and lymphocyte count decreased in cases with mild and moderate infections, while procalcitonin, erythrocyte sedimentation rate, interleukin-6, D-dimer, and C4 levels increased. Advanced age, non-vaccination, and underlying comorbid diseases were high-risk factors for disease progression in patients. However, dynamic monitoring of blood routine parameters, A/G ratio, and inflammatory indicators facilitated the prediction of disease progression.

Luciferase assay to screen tumour-specific promoters in lung cancer.

OBJECTIVE: Specific promoters could improve efficiency and ensure the safety of gene therapy. The aim of our study was to screen examples for lung cancer. METHODS: The firefly luciferase gene was used as a reporter, and promoters based on serum markers of lung cancer were cloned. The activity and specificity of seven promoters, comprising CEACAM5 (carcinoembryonic antigen, CEA), GRP (Gastrin-Releasing Peptide), KRT19 (cytokeratin 19, KRT), SFTPB (surfactant protein B, SP-B), SERPINB3 (Squamous Cell Carcinoma Antigen, SCCA), SELP (Selectin P, Granule Membrane Protein 140 kDa, Antigen CD62, GMP) and DKK1 (Dickkopf-1) promoters were compared in lung cancer cells to obtain cancer-specific examples with strong activity. RESULTS: The CEACAM5, DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB promoters were cloned. Furthermore, we successfully constructed recombinant vector pGL-CEACAM5 (DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB) contained the target gene. After cells were transfected with recombinant plasmids, we found that the order of promoter activity from high to low was SERPINB3, DKK1, SFTPB, KRT19, CEACAM5, SELP and GRP and the order for promoters regarding specificity and high potential were SERPINB3, DKK1, SELP, SFTPB, CEACAM5, KRT19 and GRP. CONCLUSION: The approach adopted is feasible to screen for new tumour specific promoters with biomarkers. In addition, the screened lung-specific promoters might have potential for use in lung cancer targeted gene therapy research.