Anti- MSP-1_(19) antibody (IgG) and reactive oxygen species (ROS) response against malaria infection in pregnancy in South Western Nigeria

Objective:Although immunity to malaria is reduced in pregnancy,the maternal immune system still continues to respond to malaria infection by the production of antibodies.IgG has been reported to play significant role in immune response against P.falciparum.Anti-MSP-119 antibody and reactive oxygen species have been shown to be protective against malaria infection in children.This work assessed the response of anti-MSP-119 antibody（a promising blood stage vaccine candidate antigen） and oxidative stress in 250 pregnant women.Methods: Blood samples were collected in dry and wet seasons.Plasmodium falciparum infection was determined by microscopy, anti-MSP-119 IgG level was investigated using ELISA.Malondiadelhyde（MDA） and reduced glutathione （GSH） were used as indicators of oxidative stress and they were quantified spectrophotometrically.Results: Parasitaemia was significantly higher（P【0.05） in wet than dry season and its level decreased with gravidity.There was a significant increase（P【0.05） in anti-MSP-119 IgG and MDA levels in the dry than wet season.Anti-MSP-119 IgG and MDA levels were significantly higher in P.falciparum positive primigravidae than P.falciparum negative primigravidae in both wet and dry seasons.In wet season anti-MSP-119 IgG level was significantly increased（P【0.05） in P.falciparum positive multigravidae than P.falciparum negative. The anti-MSP-119 IgG and MDA were significant higher in P.falciparum positive multigravidae than primigravidae. Reduced glutathione（GSH） level was significantly reduced（P【0.05） among malaria positive than malaria negative patients in both seasons.Conclusion:This study suggests that IgG and MDA response were positively associated with the presence of malaria infection.

Value of routine dengue diagnosis in endemic countries

Dengue is one of the most common arthropod-borne viral diseases in humans and it is a leading cause of illness and death in the tropical and subtropical regions of the world. It is thought to account for 400 million cases annually among approximately 3.97 billion people at risk of infection in 128 endemic countries. Despite the global prevalence of the disease, the availability of a vaccine is limited in most countries in the endemic areas. Most endemic countries in South America, South East Asia and Africa serve as attractive touristic sites for people from non-endemic countries who become infected and export the virus to dengue-free regions. Dengue fever typically resembles malaria and in endemic countries most cases of dengue are treated as presumptive malaria. Consequently, routine dengue diagnosis among persons with fever will offer early treatment and reduce the burden of the disease. Also, routine testing among travellers from endemic countries will reduce importation and prevent the geographical expansion of dengue. In this essay, we seek to highlight the usefulness of routine dengue testing in endemic countries.

Antiplasmodial Efficacy of Crude Cocoa Powder Extract on CD4+ T-Cell Counts of <i>Plasmodium berghei</i>Infected BALB/c Mice

Background: Drug resistance in malaria warrants the need for alternative therapy from plant food nutrients. The search for novel anti-malarial control spurred a great interest in cocoa which has been portrayed as immune booster against malaria. This study was geared towards estimation of CD4+ cells of P. berghei infected mice treated with cocoa powder extract (CPE) to provide substantive scientific evidence to authenticate the anecdotal report. Methods: Brine shrimp toxicity assay was done to determine LC50 of crude cocoa powder extract. The mice were infected with 1 × 107 of ANKA and NK65 strains of Plasmodium berghei intraperitoneally, while graded doses of the extract were administered by an intra-gastric intubation based on the body weight of mice. Blood samples were analyzed for microscopy and flow cytometry for CD4+ cell counts. Results: The onset of infection was delayed in the group treated before inoculations on day 3 and the level of P. berghei parasitemia was positively associated with induction of CD4+ cells while the negative control group that received normal saline had progressive increase of parasitemia. The mean survival time could not go beyond day14 in ANKA, though both strains responded to CPE in a similar way with chloroquine as a positive control. The CD4+ cells counted increased in both strains treated before and during inoculations and the episodes of malaria was suppressed compared with the control. Conclusion: This study has demonstrated that the antiplasmodial activity of CPE was associated with the level of CD4+ T-cells proliferation which initiated the protective immune response. This therefore calls for efforts to ensure adequate intake of cocoa powder to boost immunity against malaria.

Expanded Scope of Bacillus Calmette-Guerin(BCG)Vaccine Applicability in Disease Prophylaxis,Diagnostics,and Immunotherapeutics

Following the discovery of the Bacillus Calmette-Guerin(BCG)vaccine,its efficacy against Mycobacterium tuberculosis was soon established,with several countries adopting universal BCG vaccination schemes for their populations.Soon,however,studies aimed to further establish the efficacy of the vaccine in different populations discovered that the vaccine has a larger effect in reducing mortality rate than could be explained by its effect on tuberculosis alone,which sparked suggestions that the BCG vaccine could have effects on other unrelated or non-mycobacterial pathogens causing diseases in humans.These effects were termed heterologous,non-specific or off-target effects and have been shown to be due to both innate and adaptive immune system responses.Experiments carried out in a bid to further understand these effects led to many more discoveries about the applicability of the BCG vaccine for the prevention,diagnosis,and treatment of certain disease conditions.As we approach the second century since the discovery of the vaccine,we believe it is timely to review these interesting applications of the BCG vaccine,such as in the prevention of diabetes,atherosclerosis,and leukemia;the diagnosis of Kawasaki disease;and the treatment of multiple sclerosis,non-muscle invading bladder cancer,and stage III melanoma.Furthermore,complications associated with the administration of the BCG vaccine to certain groups of patients,including those with severe combined immunodeficiency and HIV,have been well described in literature,and we conclude by describing the mechanisms behind these complications and discuss their implications on vaccination strategies,especially in low-resource settings.

Efficacy of praziquantel in the treatment of Schistosoma haematobium infection among school-age children in rural communities of Abeokuta, Nigeria

Background:Chemotherapy with praziquantel(PZQ)has been the cornerstone of schistosomiasis control over the last two decades.Being the only available drug for the treatment of over 200 million people worldwide,continuous monitoring of PZQ efficacy under the pressure of widespread use is therefore advocated.Methods:The efficacy of taking two doses of oral PZQ for the treatment of Schistosoma haematobium was examined among school children in Nigeria.Urine specimens were collected from 350 school children and examined using the filtration technique.Blood was collected for packed cell volume(PCV)estimation,and the weight and height of each child were estimated.S.haematobium egg positive pupils were treated with two oral doses of PZQ at 40 mg/kg with a four-week interval in between.Drug efficacy was determined based on the egg reduction rate(ERR).Results:Among 350 school children,245(70.0%)-of which 132 were males and 113 were females,with an age range of 4 to 15 years-were diagnosed with S.haematobium.All the 245 infected children received a single oral dose of 40 mg/kg PZQ twice with a four-week interval in between and were followed up for 12 weeks.At four,eight and twelve weeks post treatment,the ERR was 57.1%,77.6%and 100%,respectively.The ERR was significantly higher among the children with a light infection compared to those with a heavy infection.One hundred and twenty-one children were egg negative at four weeks post treatment,among which 1(6.3)and 120(52.4%)had heavy and light infections,respectively.Following the second round of treatment,the cure rate at eight weeks and twelve weeks was 85.3%and 100%,respectively.Conclusion:This study demonstrated the efficacy of taking two doses of oral PZQ for the treatment of urinary schistosomiasis among school children in Nigeria.