Objective: The aim of this study is to investigate the immunomodulatory properties of fruits and leaves of Capparis spinosa in mice.Methods: The effect of methanolic extracts of C. spinosa on immune system were assessed by applying several approaches such as Lymphocyte proliferation assay in presence of mitogen (Concanavalin A), delayed-type hypersensitivity (DTH) response, humoral response and Cyclophosphamide-induced immunosuppression.Results: Administration of methanolic extracts at doses 100 and 200 mg/kg produced statistically significant results as evidenced by the increase in delayed type hypersensitivity (DTH) response (P<0.05), enhanced the total WBC level in the cyclophosphamide induced myelosuppression model (p<0.01). These extracts also showed significant increase in humoral antibody (HA) titre (P<0.05, P<0.01) at dose 200 mg/ml. Equally, C. spinosa extracts evoked a significant (p<0.05, P<0.01) increase in mitogen-induced lymphocyte proliferation.Conclusions: The results demonstrated that both the plant parts extracts exert a marked immunostimulatory effect on the mouse immune system
