Immunomodulatory activity of methanolic leaf extract of moringa oleifera in animals.

Aim: The aim of the present study was to investigate the immunomodulatory action of methanolic extract of Moringa oleifera (MEMO) in an experimental model of immunity. The cellular immunity was evaluated using neutrophil adhesion test, cyclophosphamide induced neutropenia and carbon clearance assay, whereas, humoral immunity was tested by mice lethality test, serum immunoglobulin estimation and indirect haemagglutination assay in animals. Administration of MEMO (250 and 750 mg/kg, po) and Ocimum sanctum (100 mg/kg, po) significantly increased the levels of serum immunoglobulins and also prevented the mortality induced by bovine Pasteurella multocida in mice. They also increased significantly the circulating antibody titre in indirect haemagglunation test. Moreover, MEMO produced significant increase in adhesion of neutrophils, attenuation of cyclophosphamideinduced neutropenia and an increase in phagocytic index in carbon clearance assay. From the above results, it can be concluded that MEMO stimulate both cellular and humoral immune response. However, low dose of MEMO was found to be more effective than the high dose.

Effect of centchroman on cellular and humoral immunity.

Centchroman (Ormeloxifene) is a nonsteroidal selective estrogen receptor modulator that is used as once a week oral contraceptive agent. The effect of centchroman on the immune system was evaluated by using different experimental models such as carbon clearance test, cyclophosphamide induced neutropenia, neutrophil adhesion test, effect on serum immunoglobulins, mice lethality test and indirect haemagglutination test. The first three models namely carbon clearance test, cyclophosphamide induced neutropenia and neutrophil adhesion test were used to study cell mediated immunity while the latter three models were used to see the effect on humoral immunity. Centchroman was administered orally at a dose of 5 mg/kg and levamisole (2.5 mg/kg/ p.o) was used as standard drug. Centchroman significantly increased the levels of serum immunoglobulins and also prevented the mortality induced by bovine Pasteurella multocida in mice. It also increased significantly the circulating antibody litre in indirect haemagglunation test. However, it did not show any significant effect on phagocytic index in carbon clearance assay and nor did influence the adhesion of neutrophils in the neutrophil adhesion test. Centchroman was also not effective in preventing the cyclophosphamde induced neutropenia. Hence, it was concluded that centchroman increases humoral immunity with no significant effect on cell mediated immunity.