Effect Of Ampicillin Sodium On Immune Response

摘要

Penicillins are B-lactam antibiotics widely used in clinical practice and they induce many allergic reactions, which can be either cellular or humoral. B-lactams are able to interact covalently with serum proteins, forming immunogenic conjugates and their metabolism can provoke a number of different antigenic determinants that have been implicated in the specificity of the immunological response. In the present study, Ampicillin Sodium (17.5mg/kg), a semi-synthetic amino penicillin was used to study its effect on immune response by measuring different immune parameters like total serum protein concentration, passive haemagglutination, total leucocyte and total lymphocyte count. The antigen used was sheep RBC. It was observed that there was no significant change in total serum protein content and antibody titre. Ampicillin caused a slight increase in total leukocyte count and slight decrease in total lymphocyte count. It can be concluded that Ampicillin does not adversely affect the specific immune response in normal rabbits. Introduction The immune system is known to be involved in the etiology and pathophysiological mechanism of several disease 12 . The function and efficiency of the immune system may be influenced by many exogenous and endogenous factors resulting in either immunosuppression or immunostimulation 34 .Studies have indicated that various antibiotics interfere with immune response 56 . Antibiotics like clindamycin and netilmycin administered at therapeutic doses to rabbits caused a significant inhibition of phagocytosis 6 . Lomefloxacin, Ofloxacin and cipropfloxacin had no effect on immune response 789 . Erythromycin, colistin and chloramphenicol markedly depressed humoral response, resulting in decreased TIg concentration in mice 10111213 .Ampicillin is a bactericidal agent which adheres to bacterial penicillin-binding proteins, inhibiting bacterial cell wall synthesis. The present study has been focused on the effect of ampicillin on immune response 14 . Methodology Experimental AnimalsNew Zealand White Rabbits (6 months old) were used for the study. They were kept under standard laboratory conditions. The animals were housed in polypropylene cages and were fed with standard rabbit chow and water ad libitum. Ethical committee in accordance with animal experimentation and care has approved all animal procedures.Rabbits were randomly divided into two groups, with each group containing six animals. Group I served as control which received 0.5ml of antigen, SRBC intramuscularly on the first day of the experiment. Group II rabbits were administered with ampicillin sodium at a dose of 17.5mg/kg body weight, iv twice daily for a period of 4 days and 0.5ml of SRBC im on the first day. Collection of Sheep red blood cells (SRBC)The area under the external jugular vein of sheep was carefully shaved avoiding any abrasions. The area was cleaned with 70% alcohol and 20ml of blood was withdrawn. The anticoagulant used was acid citrate solution. Later SRBC was washed with phosphate buffer solution (PBS) three times at 150g for 10minutes. A 1% suspension of the packed SRBC was then prepared.Selection of doseThe rabbit dose was calculated on the basis of surface area ratio 15 .Immunization procedureThe rabbits were divided into two groups-control and test. Ampicillin sodium at a dose of 17.5mg/kg, iv and SRBC (0.5 ml, im) were administered to the test group. The control animals were administered with the antigen, SRBC (0.5ml, im). Blood was withdrawn from the marginal ear vein prior to the administration of drugs and on 1 st , 7 th , 14 th , 21 st and 28 th day after immunization 8 . It was centrifuged, serum separated and stored at -40oC. The serum obtained was used for the estimation of antibody titre 16 , total serum protein 1718 , total leucocyte count 19 and total lymphocyte count 19 .Passive haemagglutinationThe sera collected were diluted two times in each subsequent well of the haeagglutination plate and equal volume of