Impact of experimental Schistosoma mansoni on Hepatitis B Vaccination.

Rabab Sayed Zalat1, Azza Moustafa Fahmy1,Amany M., Hegab 3 ,Ibrahim Rabea1

and Mona Magdy2

AbstractVaccination is an important measure to control infectious diseases but absent or weakresponses to vaccines represent a problem. It has been proved that chronic helminthinfection is one of contributing causes for absent or weak

response to some vaccines.The aim of the present work is studied the effects of S. mansoni infection on theefficacy of hepatitis B vaccine in experimental mice. In the present study HBVvaccine 0.1 µg/g body weight was injected via dorsal subcutaneous injection, for three

times /week for two weeks before and after S. mansoni infection. Parasitological,immunological, histopathology parameters and the associated splenic cytokines werestudied. Reduction in worm burden was associated with reduction in ova count and

changes in oogram pattern which were mainly due to PZQ treatment. Subcutaneousinjection of hepatitis B vaccine before S. mansoni infection or at day 14 or 35 PIreduced the total worm burden by 3.1%, 18.8% and 40.6% respectively. While,

administration of hepatitis B vaccine combined with PZQ treatment significantlyreduced the total worm burden, egg load in the intestine and the liver. Increasingreduction in granuloma diameter, elevation of cytokines levels was observed in the

groups treated with PZQ alone or combined with hepatitis B vaccine. Treatment ofHBV started at day 35 p.i. showed the greatest reduction in granuloma diameter (65.4%) and inflammatory cells. while treatment the infected mice with HBV pre-infectionshowed the lowest reduction in

granuloma diameter reach to 19.9 % when comparedwith their corresponding infected untreated groups. In the current study the meanvalues of liver concentration of malondialdehyde (MDA), glutathione (GSH) andnitric oxide (NO) were measured. There was

no significant change in (GSH) and(MDA) concentrations in infected groups vaccinated with HBV alone, (P 0.05)compared with infected group. The concentrations of GSH and MDA in groupstreated with PZQ alone or combined with HBV antigen showed significant

ameliorations in their levels compared to infected group. The hepatic nitric oxideconcentration was very highly significant lowered (P< 0.001) when PZQ wasadministered alone or to vaccinated animals with HBV. In conclusion, eradication ofschistosomal worms is helpful to improve the

effect of HBV vaccination. The currentstudies in mice suggest that to improve the efficacy of HBV vaccination inschistosome infected humans it may be valuable to treat them with praziquantel(PZQ) some time prior to HBV vaccinatioAbstract

Vaccination is an important measure to control infectious diseases but absent or weakresponses to vaccines represent a problem. It has been proved that chronic helminthinfection is one of contributing causes for absent or weak response to some vaccines.The aim of the present work is studied the

effects of S. mansoni infection on theefficacy of hepatitis B vaccine in experimental mice. In the present study HBVvaccine 0.1 µg/g body weight was injected via dorsal subcutaneous injection, for threetimes /week for two weeks before and after S. mansoni

infection. Parasitological,immunological, histopathology parameters and the associated splenic cytokines werestudied. Reduction in worm burden was associated with reduction in ova count andchanges in oogram pattern which were mainly due to PZQ

treatment. Subcutaneousinjection of hepatitis B vaccine before S. mansoni infection or at day 14 or 35 PIreduced the total worm burden by 3.1%, 18.8% and 40.6% respectively. While,administration of hepatitis B vaccine combined with PZQ

treatment significantlyreduced the total worm burden, egg load in the intestine and the liver. Increasingreduction in granuloma diameter, elevation of cytokines levels was observed in thegroups treated with PZQ alone or combined with

hepatitis B vaccine. Treatment ofHBV started at day 35 p.i. showed the greatest reduction in granuloma diameter (65.4%) and inflammatory cells. while treatment the infected mice with HBV pre-infectionshowed the lowest reduction in granuloma diameter reach to 19.9 % when compared

with their corresponding infected untreated groups. In the current study the meanvalues of liver concentration of malondialdehyde (MDA), glutathione (GSH) andnitric oxide (NO) were measured. There was no significant change in (GSH) and

(MDA) concentrations in infected groups vaccinated with HBV alone, (P 0.05)compared with infected group. The concentrations of GSH and MDA in groupstreated with PZQ alone or combined with HBV antigen showed significantameliorations in their levels compared to

infected group. The hepatic nitric oxideconcentration was very highly significant lowered (P< 0.001) when PZQ wasadministered alone or to vaccinated animals with HBV. In conclusion, eradication ofschistosomal worms is helpful to improve the effect of HBV

vaccination. The currentstudies in mice suggest that to improve the efficacy of HBV vaccination inschistosome infected humans it may be valuable to treat them with praziquantel(PZQ) some time prior to HBV vaccinatioAbstract

Vaccination is an important measure to control infectious diseases but absent or weakresponses to vaccines represent a problem. It has been proved that chronic helminthinfection is one of contributing causes for absent or weak response to some vaccines.The aim of the present work is studied the

effects of S. mansoni infection on theefficacy of hepatitis B vaccine in experimental mice. In the present study HBVvaccine 0.1 µg/g body weight was injected via dorsal subcutaneous injection, for threetimes /week for two weeks before and after S. mansoni

infection. Parasitological,immunological, histopathology parameters and the associated splenic cytokines werestudied. Reduction in worm burden was associated with reduction in ova count andchanges in oogram pattern which were mainly due to PZQ

treatment. Subcutaneousinjection of hepatitis B vaccine before S. mansoni infection or at day 14 or 35 PIreduced the total worm burden by 3.1%, 18.8% and 40.6% respectively. While,administration of hepatitis B vaccine combined with PZQ

treatment significantlyreduced the total worm burden, egg load in the intestine and the liver. Increasingreduction in granuloma diameter, elevation of cytokines levels was observed in thegroups treated with PZQ alone or combined with

hepatitis B vaccine. Treatment ofHBV started at day 35 p.i. showed the greatest reduction in granuloma diameter (65.4%) and inflammatory cells. while treatment the infected mice with HBV pre-infectionshowed the lowest reduction in granuloma diameter reach to 19.9 % when compared

with their corresponding infected untreated groups. In the current study the meanvalues of liver concentration of malondialdehyde (MDA), glutathione (GSH) andnitric oxide (NO) were measured. There was no significant change in (GSH) and

(MDA) concentrations in infected groups vaccinated with HBV alone, (P 0.05)compared with infected group. The concentrations of GSH and MDA in groupstreated with PZQ alone or combined with HBV antigen showed significantameliorations in their levels compared to

infected group. The hepatic nitric oxideconcentration was very highly significant lowered (P< 0.001) when PZQ wasadministered alone or to vaccinated animals with HBV. In conclusion, eradication ofschistosomal worms is helpful to improve the effect of HBV

vaccination. The currentstudies in mice suggest that to improve the efficacy of HBV vaccination inschistosome infected humans it may be valuable to treat them with praziquantel(PZQ) some time prior to HBV vaccinatio1 Parasitology Department TBRI Imbaba – Giza-Egypt 2 Pathology Department TBRI Imbaba – Giza-Egypt 3 Developmental pharmacology Department National Organization for Drug control and Research Egypt

Abstract

Vaccination is an important utility to control infectious diseases, but absent or weak responses to vaccines represent a problem. It has been proved that chronic

helminth infection is one of the contributing causes for absent or weak response to some vaccines. The aim of the present work studied the effects of. Schistosoma mansoni infection on the efficacy of hepatitis B vaccine (HBV) in experimental mice. In the present study HBV vaccine 0.1 µg/g body weight was injected via dorsal subcutaneous injection, for three times/week for two weeks before and after S. mansoni infection. Parasitological, immunological, histopathological parameters, and the associated hepatic cytokines were studied. Reduction in worm burden was associated with reduce in ova count and changes in oogram pattern which were

mainly due to praziquantel (PZQ) treatment. Subcutaneous injection of (HBV) vaccine before S. mansoni infection or at day 14 or 35 PI reduced the total worm burden by 3.1%, 18.8% and 40.6% respectively. While, administration of (HBV) vaccine combined with PZQ treatment significantly reduced the total worm burden, egg load in the intestine and the liver. Severely reduced granuloma diameter, and significantly elevated cytokines levels in the groups treated with PZQ alone or combined with (HBV) vaccine. Treatment of HBV started at day 35 PI combined with PZQ, showed the greatest reduction in granuloma diameter (65.4 %) and inflammatory cells. While treatment the infected mice with HBV pre-infection showed the lowest reduction in granuloma diameter reaching to 19.9 % when compared with their corresponding infected untreated groups. In the current study mean values of liver concentration of malondialdehyde (MDA), glutathione (GSH) and nitric oxide (NO) were measured. There was no significant change in (GSH) and (MDA) concentrations in infected groups vaccinated with HBV alone, (P 0.05) compared with infected group. The concentrations of GSH and MDA in groups treated with PZQ alone or combined with HBV vaccine showed significant ameliorations in their levels compared to infected group. The hepatic nitric oxide concentration was very highly significant lowered (P< 0.001) when PZQ was administered alone or to vaccinated animals with HBV. In conclusion, eradication of schistosomal worms is helpful to improve the effect of HBV vaccination. The current studies in mice suggest that pre-treatment with praziquantel (PZQ) prior to HBV vaccination improve the efficacy of HBV vaccination in schistosoma infected human.

Key Words: Schistosoma mansoni Hepatitis B vaccine, praziquantel (PZQ).