Immunoglobulin G (IgG) specific responses to recombinant Qß displayed MSP3 and UB05 in plasma of asymptomatic Plasmodium falciparum-infected children living in two different agro-ecological settings of Cameroon.

Introduction: in areas with intense perennial malaria transmission, limited data is available on the impact of environmental conditions especially rainfall on naturally acquired immunity against promising malaria vaccine candidates. For this reason, we have compared IgG antibody responses specific to Plasmodium spp. derived MSP3 and UB05 vaccine candidates, in plasma of children living in two areas of Cameroon differing in rainfall conditions. Methods: data about children less than 5 years old was collected during the years 2017 and 2018. Next malaria asymptomatic P. falciparum (Pf) infected children were selected following malaria test confirmation. MSP3 and UB05 specific IgG antibody responses were measured in participant´s plasma using enzyme-linked immunosorbent assay (ELISA). Results: interestingly, IgG antibody responses specific to UB05 were significantly higher (p<0.0001) in Pf-negative children when compared to their asymptomatic Pf-infected counterparts living in monomodal rainfall areas. In contrast, a significantly higher (p<0.0001) IgG response to MSP3 was observed instead in asymptomatic Pf-infected children in the same population. In addition, IgG responses specific to UB05 remained significantly higher in bimodal when compared to monomodal rainfall areas irrespective of children´s Pf infection status (p<0.0055 for Pf-positive and p<0.0001 for negative children). On the contrary, IgG antibody responses specific to MSP3 were significantly higher in bimodal relative to monomodal rainfall areas (P<0.0001) just for Pf-negative children. Conclusion: thus IgG antibody responses specific to UBO5 are a better correlate of naturally acquired immunity against malaria in Pf-negative Cameroonian children especially in monomodal rainfall areas.

COVID-19 vaccine hesitancy among staff and students in a Nigerian tertiary educational institution.

BACKGROUND: COVID-19 was first reported on 31 December 2019 and has so far claimed over 2,000 lives in Nigeria. Through global and national efforts, about 4 million doses of the AstraZeneca vaccine was distributed and used in Nigeria from March 2021. Vaccine hesitancy could pose a serious problem for COVID-19 prevention and control. OBJECTIVES: To estimate the proportion of the Nnamdi Azikiwe University community that is willing to be vaccinated against COVID-19; level of hesitancy and its associated factors. METHODS: A cross-sectional survey was conducted using online Google form distributed to staff and students of the university via different WhatsApp groups. The outcome measures were the proportion of persons willing to be vaccinated, vaccine hesitancy rates and reasons for this hesitancy. Data were analyzed using SPSS version 23 and Minitab version 19. Bivariate analysis was performed by the chi-square test, Odds Ratios (ORs) and statistical significance was accepted when p-value is < 0.05. RESULTS: Only 349 of the survey responses were analyzed in the survey. Results show that 34.70 ± 5.00% of the university community were willing to receive the COVID-19 vaccine when it is offered to them. The COVID-19 hesitancy rate among staff and students was 65.04 ± 5.00%. It was discovered that marital status (OR = 2.06), age (OR = 0.802) and christian denominational affiliation (OR = 0.366) influenced respondents' perception of COVID-19 vaccination. Gender, occupation, previous vaccination experience, awareness of COVID-19 and previous symptoms of COVID-19 did not significantly (p = 0.05) influence respondents' willingness to be vaccinated. CONCLUSION: COVID-19 vaccine hesitancy is high among staff and students in a Nigerian university and is significantly influenced by marital status, respondents' age and christian denominational affiliation.

Dendritic cell targeted HIV-1 gag protein vaccine provides help to a recombinant Newcastle disease virus vectored vaccine including mobilization of protective CD8+ T cells.

INTRODUCTION: Recombinant Newcastle Disease virus (rNDV) vectored vaccines are safe mucosal applicable vaccines with intrinsic immune-modulatory properties for the induction of efficient immunity. Like all viral vectored vaccines repeated inoculation via mucosal routes invariably results to immunity against viral vaccine vectors. To obviate immunity against viral vaccine vectors and improve the ability of rNDV vectored vaccines in inducing T cell immunity in murine air way we have directed dendritic cell targeted HIV-1 gag protein (DEC-Gag) vaccine; for the induction of helper CD4+ T cells to a Recombinant Newcastle disease virus expressing codon optimized HIV-1 Gag P55 (rNDV-L-Gag) vaccine. METHODS: We do so through successive administration of anti-DEC205-gagP24 protein plus polyICLC (DEC-Gag) vaccine and rNDV-L-Gag. First strong gag specific helper CD4+ T cells are induced in mice by selected targeting of anti-DEC205-gagP24 protein vaccine to dendritic cells (DC) in situ together with polyICLC as adjuvant. This targeting helped T cell immunity develop to a subsequent rNDV-L-Gag vaccine and improved both systemic and mucosal gag specific immunity. RESULTS: This sequential DEC-Gag vaccine prime followed by an rNDV-L-gag boost results to improved viral vectored immunization in murine airway, including mobilization of protective CD8+ T cells to a pathogenic virus infection site. CONCLUSION: Thus, complementary prime boost vaccination, in which prime and boost favor distinct types of T cell immunity, improves viral vectored immunization, including mobilization of protective CD8+ T cells to a pathogenic virus infection site such as the murine airway.

comparative study of carbohydrate antigen 19-9 in sickle cell disease subjects and controls in Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria.

BACKGROUND: Sickle cell disease is characterized by chronic complications that affect almost all body organs. Pancreatic disease is rare in SCD. CA 19-9 is a non-specific surrogate marker for pancreatic disease especially carcinoma. CA 19-9 levels have not been evaluated in SCD patients in our environment. OBJECTIVES: The study aimed to compare the levels of CA 19-9 in homozygous sickle cell disease subjects in steady state with those of (Hb AS) and normal healthy subjects (Hb AA). METHOD: Seventy nine subjects including 39 Hb SS, 19 Hb AS and 21 Hb AA subjects were recruited in a cross-sectional study in Nnamdi Azikiwe University and Teaching Hospital. Haemoglobin genotype and CA 19-9 estimation were done using Hb electrophoresis and enzyme linked immunosorbent assay respectively. Data was analyzed with IBM SPSS 21. P value was set at 0.05. RESULT: The mean CA 19-9 (U/ml) level in Hb SS, Hb AS and Hb AA were 13.6 ± 7.6, 15.3 ± 9.9, and 20.0 ± 15.9 respectively. [Reference value <37U/ml] CA 19-9 was significantly lower in Hb SS compared to Hb AA subjects (p = 0.035). CONCLUSION: Low levels of CA 19-9 in Hb SS may suggest reduced pancreatic disorders in SCA.