EVALUATION OF THE IMMUNE RESPONSES INDUCED BY EXPERIMENTAL INFECTION OF (BALB/c) MICE WITH SALMONELLA HADAR

Abstract

The present study bases on evaluate the immune responses due to experimental infection of (BALB/c) mice by Salmonella hadar .The experiment was carried out on eighty mice of both genders with age range (6 -8) weeks old, the mice were divided randomly into three groups (group A:-contain 20 mice were administrated orally with infectious dose (1.5×10 7 C.F.U\ml) ,group B:-contain 40 mice were administrated orally with LD 50 dose (1.5×10 9 C.F.U\ml) and groupC:-contain 20 mice which inoculated orally with 1 ml of PBS (pH=7.2) and consider as control group).The study has noticed that the experimentally infected mice are able to induce humoral immune response which represented by producing antibody against Salmonella hadar and this production was elevated after two weeks of administration and reach the peak after four weeks post infection then decline sharply after passage of six weeks post infection in both groups (A and B) but the titration of the antibodies in group B was higher on that recorded in group A.It is obvious that S. hadar is able to induce cellular immune response during experimental infection with infectious dose and LD 50 dose and the results of delayed type hypersensitivity have showed increases in the thickness of the right footpads of the mice of both groups (A and B) and the highest mean of the thickness was after 24 hours post immunization.Finally, we concluded that Salmonella hadar in infected the host was able to induce both humoral and cellular immune responses and these responses are dose dependent.