human cellular immune response to the saliva of phlebotomus papatasi is mediated by il-10-producing cd8+ t cells and th1-polarized cd4+ lymphocytes人类细胞免疫反应的唾液phlebotomus papatasi是由il-10-producing cd8 + t细胞和th1-polarized cd4 +淋巴细胞.pdfVIP

Human Cellular Immune Response to the Saliva of Phlebotomus papatasi Is Mediated by IL-10-Producing CD8+ T Cells and Th1-Polarized CD4+ Lymphocytes 1. ´ 1 . 1 1 Maha Abdeladhim , Melika Ben Ahmed * , Soumaya Marzouki , Nadia Belhadj Hmida , Thouraya 2 3 3 1,2 Boussoffara , Nabil Belhaj Hamida , Afif Ben Salah , Hechmi Louzir 1 Department of Clinical Immunology, Pasteur Institute of Tunis, Tunis, Tunisia, 2 LIVGM, Pasteur Institute of Tunis, Tunis, Tunisia, 3 Department of Medical Epidemiology, Pasteur Institute of Tunis, Tunis, Tunisia Abstract Background: The saliva of sand flies strongly enhances the infectivity of Leishmania in mice. Additionally, pre-exposure to saliva can protect mice from disease progression probably through the induction of a cellular immune response. Methodology/Principal Findings: We analysed the cellular immune response against the saliva of Phlebotomus papatasi in humans and defined the phenotypic characteristics and cytokine production pattern of specific lymphocytes by flow cytometry. Additionally, proliferation and IFN-c production of activated cells were analysed in magnetically separated CD4+ and CD8+ T cells. A proliferative response of peripheral blood mononuclear cells against the saliva of Phlebotomus papatasi was demonstrated in nearly 30% of naturally exposed individuals. Salivary extracts did not induce any secretion of IFN-c but triggered the production of IL-10 primarily by CD8+ lymphocytes. In magnetically separated lymphocytes, the saliva induced the proliferation of both CD4+ and CD8+ T cells which was further enhanced after IL-10 blockage. Interestingly