Effect of levamisole administration on immunogenic and protective capacity of Brucella abortus RB51

Abstract

Background: Brucella abortus strain RB 51 is a rough strain that was derived after multiple passages of virulent strain 2308. Levamisole, a potent anthelmintic that is widely used in veterinary medicine, is also known as an immune stimulant. Aim and Objectives: Determine the capability of levamisole to enhance the humoral antibody response and cellmediated immunity as well as protective capacity of RB 51 vaccine in mice against challenge with virulent Brucella melitensis strain. Materials and Methods: Six groups of 7-8-week-old female Bulb/C mice were used. Group I was vaccinated I/P with 5 × 108 colony-forming units (CFU) of RB 51 strain. Group II was vaccinated I/P with 5 × 108 CFU of RB 51 strain simultaneously injected (at 0 day) s/cu with 12.5 mg/Kg levamisole. Group III was vaccinated I/P with 5 × 108 CFU of RB 51 strain and injected at 7-day postvaccination with 12.5 mg/Kg levamisole. Group IV was vaccinated I/P with 5 × 108 CFU of RB 51 strain and injected at the day of vaccination (0 day) and 7-day postvaccination with 12.5 mg/Kg levamisole. Group V was injected with levamisole alone. Group VI was kept as control group. 8-week postvaccination; all vaccinated as well as control animals groups received I/P challenge of 2 ml dose of 2 × 104 CFU/ml of virulent strain of B. melitensis biovar 3. Results: (Groups III and IV) At the day of vaccination (0 day) and 7-day postvaccination showed the highest significant serum antibody titer measured by ELISA all over the experimental period as well as increase in delayed type hypersensitivity (DTH) response 48 h after elicitation by intradermal inoculation of B. abortus soluble antigen compared to vaccinated control group (Group I). While RB 51 vaccinated and simultaneously treated with levamisole (Group II) showed mild elevation in antibody titer as well as the lowest significant increase in DTH response compared to vaccinated control group. Bioassay test of challenged mice groups showed significant improvement in the resistance of vaccinated groups treated with levamisole either 7-day postvaccination (Group III) or 0 and 7 days postvaccination (Group IV) which showed 10% bacteriologically positive mice, whereas only 30% of the vaccinated control mice (Group I) and vaccinated simultaneously treated with levamisole (Group II), were bacteriologically positive.

Efficacy of Locally Available Anthelmintics against Helminths of Dairy Cows in Gazipur, Bangladesh

“…The resistant helminth against Levamisole in BSMRAU dairy farm was not developed after a third time indiscriminate treatment using different types of anthelmintics which indicates that Levamisole resistance develops at a slower rate than Fenbendazole, Ivermectin, and Triclabendazole in dairy cows. The probable reason for the different findings on Levamisole might be due to the immune stimulant properties of Levamisole (Mansour, 2018). These findings indicate that Levamisole is still effective for the treatment of dairy cows in Gazipur, Bangladesh.…”

The potential immunomodulatory effect of levamisole in humans and farm animals

“…Oral or injectable administration of levamisole has been studied for weight gain, mucosal protection by assessment of IgA status, and humeral immune stimulation at different ages in pigs [41] . Concomitant use of levamisole with viral and bacterial vaccines in pigs has shown that levamisole not only improves antibody production but also increases the half-life of antibodies in pigs [43– 46] . Interestingly, levamisole reduced cortisol levels after experimentally induced stress on pigs for 16 days.…”

“…Unfortunately, the endometriosis pathophysiology is not very clear, and it is believed that endometrial cells evade apoptosis and the immunosurveillance system in the peritoneal cavity [65] . Recent studies have revealed that several factors contribute to endometriosis, including reduced T cell reactivity and natural killer cytotoxicity, activation of B cells, elevated antibody production, increased number and activation of peritoneal macrophages, and alterations in inflammatory mediators [46] . Levamisole was used in experimental endometriosis, either alone or in combination with other agents, as a treatment approach.…”