recombinant HBV vaccine (Hansenula Polymorpha)

Antibody reactivity to the VAR2CSA DBL5 domain among pregnant women in Northern Ghana.

Adda Richmond Balinia RB, Dassah Sylvester Donne SD, Mohammed Abdul-Rashid AR, Kulariba Jonah J et al.

Pregnancy-associated malaria (PAM), caused predominantly by Plasmodium falciparum, remains a major contributor to maternal and neonatal morbidity in malaria-endemic regions. Placental sequestration of infected erythrocytes is mediated by the parasite protein VAR2CSA, a leading target for PAM vaccine development. However, extensive antigenic polymorphism within VAR2CSA complicates the identification of broadly protective vaccine candidates. Conserved subdomains such as the Duffy Binding-Like 5 (DBL5) domain may contribute to naturally acquired antibody responses during pregnancy. To assess the specificity of DBL5-directed immunity, hepatitis B virus (HBV)-infected pregnant women were included as a non-malarial infectious comparator group. This study evaluated plasma immunoglobulin G (IgG) reactivity to DBL5 and examined its concordance with antibody reactivity to full-length VAR2CSA among pregnant women in Northern Ghana. Plasma samples from 156 pregnant women were purposively selected from a cross-sectional antenatal cohort and categorised into P. falciparum-infected (n = 60), HBV-infected (n = 60), and co-infected (n = 36) groups. Recombinant DBL5 was expressed in E. coli, purified, and used in indirect enzyme-linked immunosorbent assays (ELISA) to measure plasma IgG reactivity. A subset of samples was tested in parallel against full-length VAR2CSA to evaluate concordance of antibody responses. Multi-tool immunoinformatics analyses were additionally performed to predict B-cell and T-cell epitopes and estimate population coverage. Plasma IgG reactivity to DBL5 differed significantly across study groups (p < 0.001), with the highest median optical density (OD450) observed among P. falciparum-infected women (1.54), compared with HBV-infected (0.88) and co-infected participants (1.20). DBL5-specific IgG responses demonstrated a strong positive correlation with reactivity to full-length VAR2CSA (Spearman's ρ = 0.75, p < 0.0001), indicating substantial concordance between recognition of the DBL5 domain and the native placental malaria antigen. Immunoinformatics analyses identified multiple conserved DBL5 regions with strong predicted HLA-binding affinity and broad estimated global population coverage. Pregnant women exposed to P. falciparum exhibit elevated plasma IgG reactivity to the VAR2CSA DBL5 domain, and these responses closely parallel antibody recognition of full-length VAR2CSA. These findings suggest that DBL5 may represent an immunologically recognisable component of naturally acquired PAM-associated antibody responses. However, given the exploratory cross-sectional design, the observed associations should be interpreted cautiously and warrant further investigation in longitudinal and functional studies evaluating the role of DBL5 in placental malaria immunity and future vaccine research.

Correction to 'Marchantia polymorpha GOLDEN2-LIKE transcriptional factor; a central regulator of chloroplast and plant vegetative development'.

Perspectives of hepatitis B treatment and vaccinations within the community in Nepal: Insights from healthcare workers.

Hogan Sam S, Shrestha Nisha N, Dixit Sameer S, Page Andrew A et al.

Hepatitis B virus (HBV) infections are a critical public health issue, especially in lower resource setting where the potential for chronic infections is increased. In Nepal an HBV vaccination program has been in place since the early 2000s, though knowledge and awareness of HBV has been recorded as being low within community settings. This study explored inequalities which may influence the overall healthcare system within Nepal regarding HBV, specifically vaccination programs, knowledge, awareness, and stigma associated with HBV. In-depth interviews (n = 21) were conducted with healthcare professionals from different healthcare districts in Nepal. These interviews were then transcribed before thematic analysis was performed. Several potential sources of inequality of service provision were identified. Awareness of HBV was reasonable among the participants; however, level of knowledge was variable. Participants felt while the vaccination program had been somewhat successful, there were still several areas in the Nepalese health system which needed to be strengthened to further mitigate risk of HBV infections. This included the need to strengthen and standardise vaccination processes within Nepal. Based on our findings, efforts to provide appropriate resources and equipment to community health centres needed to be reinforced. An increase is also needed in education and awareness programs around health issues, specifically those involving infectious diseases such as Hepatitis B at the community level. There also should be continued commitment to enhancing the healthcare services provided in rural and other underserved areas of Nepal.

Proteomics- and immunoinformatics-based design of a multi-epitope vaccine ZZ1 against Glaesserella parasuis.

Wang Zesong Z, Wei Wenbin W, Feng Shifan S, Jia Chaoying C et al.

Glaesserella parasuis (G. parasuis) is a prevalent opportunistic pathogen of the porcine upper respiratory tract, causing substantial economic losses to the global swine industry. Current commercial vaccines exhibit suboptimal heterologous cross-protection and inherent biosafety concerns, highlighting the need for a safe, broadly effective multi-serotype vaccine. This study targeted outer membrane proteins (OMPs) with robust cross-serotype immunogenicity from virulent G. parasuis strains. Comparative proteomic analysis of five strains identified highly abundant, co-expressed OMPs, which were screened based on antigenicity and physicochemical properties. Epitope prediction for helper T lymphocytes (HTL), cytotoxic T lymphocytes (CTL), and B-cells was performed on selected OMPs. Immunodominant epitopes were concatenated using flexible linkers and fused with the TLR2 agonist phenol-soluble modulin α4 (PSMα4) to engineer a multi-epitope vaccine, designated ZZ1. Screening yielded eight conserved OMPs with high antigenicity, hydrophilicity, and thermostability, from which 6 HTL, 7 CTL, and 11 B-cell epitopes were predicted. Immunoinformatic evaluations revealed that ZZ1 possesses a high antigenicity score of 1.018 (threshold: 0.4) and is non-allergenic and non-toxic. Following successful expression, in vivo trials demonstrated that recombinant ZZ1 elicited robust, specific IgG antibody responses. Challenge tests in piglets revealed 100% protective efficacy against G. parasuis serotype 4, and 80% against serotypes 5 and 13. These findings indicate that ZZ1 is a promising candidate capable of conferring broad cross-protection against multiple prevalent G. parasuis serotypes, offering an innovative strategy for next-generation subunit vaccine development.