Background. Health care workers (HCWs) constantly stand at a high risk of exposure to the hepatitis B virus because of the nature of their work. Hence, it is mandatory for HCWs to undergo hepatitis B vaccination. However, most HCWs in Ghana do not check their HBsAb titre after completion of their primary vaccination. This study assessed the prevalence of HBsAg and the seroconversion rate among vaccinated health care workers in the Ashanti Region, Ghana. Materials and Methods. A semistructured open-ended questionnaire was pretested and administered to 424 HCWs. Two (2) ml of blood was drawn and qualitative analyses (HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb) were done on the blood samples. Samples that tested positive to HBsAb were quantified using ELISA. Data obtained were analysed using GraphPad Prism 9. Results. Out of the 424 study participants, 271 (63.9) were females and 153 (36.1) were males. Seroconversion (1mIU/mL) and seroprotection (10mIU/mL) through vaccination only among study participants were 67.5 (n/N=286/424) and 58.0 (n/N=246/424), respectively. Prevalence of hepatitis B viral infection was 2.4 (n/N=10/424). Anti-HBc seropositivity was 13.2, and anti-HBs seronegativity was 24.1. 2.4 (n/N=10/424) of study participants were negative to HBsAg but positive to HBcAb. In addition, 8.5 (n/N=36/424) of the study participants were seroprotected due to exposure and recovery from previous HBV infection. Age, the number of doses received, taking a booster dose, and keeping a vaccination record card were significant factors influencing seroconversion status. Conclusion. This study reaffirms the need for HCWs to undergo a supervised primary hepatitis B vaccination course. Postvaccination serological testing should be done for all HWCs to confirm immunity and reduce their chances of contracting HBV infection.

Tuberculosis (TB) is characterized by immunopathology in the blood and monocytes have been shown to be highly sensitive to plasma environment changes in TB patients. Here, we investigated TB plasma effects on 'reference monocytes' using RNA sequencing to characterize a potential immunomodulatory role of monocytes in TB. Candidate pathways induced by plasma samples from TB patients (n=99) compared to healthy controls (n=62) were analyzed for changes in signal transduction, phenotype and secreted cytokines by flow cytometry. Finally, potential implications were characterized in blood samples from corresponding patients and controls. Reference monocytes treated with TB plasma showed an enrichment of pathways involved in inflammation and chemotaxis. Inflammatory cytokines were accompanied by enhanced phosphorylation of STAT molecules (i.e., STAT1/3/5) and strong positive correlations were detected for Interleukin (IL)-6 only in TB plasma-treated monocytes. Moreover, monocyte chemokine receptors (i.e., CCR-1, CCR-5) and pro-inflammatory chemokines (i.e., CXCL-1, CXCL-2, CXCL-8, G-CSF, CCL-2) that attract granulocytes and monocytes were significantly higher in TB plasma-treated monocytes. Notably, corresponding clinical samples also showed higher plasma levels for a subset of inflammatory cytokines/chemokines and, in particular, high IL-6 levels correlated positively with accumulation of neutrophil granulocytes in the blood of TB patients. Finally, monocytes from TB patients were characterized by increased chemokine receptor expression, higher proportions of a CCR-2⁺ subpopulation and aberrant high SOCS3 expression. These results suggest that monocytes may play a significant role in amplifying plasma immunopathology, leading to sustained mobilization and accumulation of neutrophil granulocytes and chronic inflammation in the blood of TB patients.

Mycobacterium (M.) bovis BCG vaccination is recommended for healthy babies after birth in several countries with a high prevalence of tuberculosis, including Ghana. Previous studies showed that BCG vaccination prevents individuals from developing severe clinical manifestations of tuberculosis, but BCG vaccination effects on the induction of IFN-γ after M. tuberculosis infection have hardly been investigated. Here, we performed IFN-γ-based T-cell assays (i.e., IFN-γ Release Assay, IGRA; T-cell activation and maturation marker assay, TAM-TB) in children who had contact with index tuberculosis patients (contacts). These contacts were classified as either being BCG vaccinated at birth (n = 77) or non-BCG-vaccinated (n = 17) and were followed up at three timepoints for a period of one year to determine immune conversion after M. tuberculosis exposure and potential infection. At baseline and month 3, BCG-vaccinated contacts had significantly lower IFN-γ levels after stimulation with M. tuberculosis-specific proteins as compared to non-BCG-vaccinated contacts. This resulted in decreased proportions of positive IGRA results (BCG-vaccinated: 60% at baseline, 57% at month 3; non-BCG-vaccinated: 77% and 88%, respectively) at month 3. However, until month 12, immune conversion in BCG-vaccinated contacts led to balanced proportions in IGRA responders and IFN-γ expression between the study groups. TAM-TB assay analyses confirmed higher proportions of IFN-γ-positive T-cells in non-BCG-vaccinated contacts. Low proportions of CD38-positive M. tuberculosis-specific T-cells were only detected in non-BCG-vaccinated contacts at baseline. These results suggest that BCG vaccination causes delayed immune conversion as well as differences in the phenotype of M. tuberculosis-specific T-cells in BCG-vaccinated contacts of tuberculosis patients. These differences are immune biomarker candidates for protection against the development of severe clinical tuberculosis manifestations.

BCG vaccination affects other diseases beyond tuberculosis by unknown—potentially immunomodulatory—mechanisms. Recent studies have shown that BCG vaccination administered during overt type 1 diabetes (T1D) improved glycemic control and affected immune and metabolic parameters. Here, we comprehensively characterized Ghanaian T1D patients with or without routine neonatal BCG vaccination to identify vaccine-associated alterations. Ghanaian long-term T1D patients (n = 108) and matched healthy controls (n = 214) were evaluated for disease-related clinical, metabolic, and immunophenotypic parameters and compared based on their neonatal BCG vaccination status. The majority of study participants were BCG-vaccinated at birth and no differences in vaccination rates were detected between the study groups. Notably, glycemic control metrics, i.e., HbA1c and IDAA1c, showed significantly lower levels in BCG-vaccinated as compared to unvaccinated patients. Immunophenotype comparisons identified higher expression of the T cell activation marker CD25 on CD8⁺ T cells from BCG-vaccinated T1D patients. Correlation analysis identified a negative correlation between HbA1c levels and CD25 expression on CD8⁺ T cells. In addition, we observed fractional increases in glycolysis metabolites (phosphoenolpyruvate and 2/3-phosphoglycerate) in BCG-vaccinated T1D patients. These results suggest that neonatal BCG vaccination is associated with better glycemic control and increased activation of CD8⁺ T cells in T1D patients.

Background Health care workers (HCWs) constantly stand a high risk of exposure to the hepatitis B virus because of the nature of their work. Hence, it is mandatory for HCWs to undergo hepatitis B vaccination. However, most HCWs in Ghana do not check their HBsAb titre after completion of their primary vaccination. This study assessed the prevalence of HBsAg and the seroconversion rate among vaccinated health care workers in the Ashanti Region, Ghana. Materials and methods A semi-structured open-ended questionnaire was pretested and administered to 424 HCWs. Two (2) ml of blood was drawn and qualitative analyses (HBsAg, HBsAb, HBeAg, HBeAb and HBcAb) were done on the blood samples. Samples that tested positive to HBsAb were quantified using ELISA. Data obtained were analysed using GraphPad Prism 9. Results Out of the 424 study participants, 271 (63.9%) were females and 153 (36.1%) were males. Seroconversion (≥1 mIU/mL) and seroprotection (≥10 mIU/mL)through vaccination onlyamong study participants were 67.5% (n/N = 286/424) and 58.0% (n/N =246/424) respectively. Prevalence of hepatitis B viral infection was 2.4% (n/N = 10/424). Anti-HBc sero-positivity was 13.2% and anti-HBs seronegativity was 24.1%. 2.4% (n/N = 10/424) of study participants were negative to HBsAg but positive to HBcAb. Additional 8.5% (n/N = 36/424) of the study participants were seroprotected due to exposure and recovery from previous HBV infection. Age, the number of doses received, taking a booster dose and keeping a vaccination record card were significant factors influencing seroconversion status. Conclusion This study reaffirms the need for HCWs to undergo a supervised primary hepatitis B vaccination course. Post-vaccination serological testing should be done for all HWCs to confirm immunity and to reduce their chances of contracting HBV infection.

'Correction to: Biomarker Development Against Infections Using Proteomics' published in 'Pharmacoproteomics'