Study of IL-12 Agonists in Macrophages from Patients with Healing and Non-Healing Forms of Cutaneous leishmaniasis

Abstract

Background: Cutaneous leishmaniasis (CL) is a self-healing disease; however, due to some reasons, in a few cases the lesion develops to a non-healing form of disease. The initial encounter of Leishmania with its host’s innate immune system is important in the outcome of infection. Although, tremendous data is available in murine model of leishmaniasis but immunological surrogate marker(s) of healing and protection in human is not yet well-defined. In this study, the level of IL-23 and IL-27 produced by peripheral blood derived macrophages from patients with healing or non-healing form of cutaneous leishmaniasis lesion were determined to explore whether IL-23 or IL-27 plays a protection role in healing process of cutaneous lesions induced by Leishmania major (L. major). Methods: 26 six patients resident in Isfahan Province, Iran, with healing or non-healing forms of cutaneous leishmaniasis caused by L. major were selected. In-vitro productions of IL-23 and IL-27 by peripheral blood derived macrophages, before and after stimulation with live L. major (MRHO/IR/75/ER) promastigotes were evaluated in these two groups and control group using the enzyme-linked immunosorbent assay (ELISA) method. Findings: The mean difference production of IL-23 and IL-27 from macrophages of patients with healing form of lesion was significantly higher than patients with non-healing form. The levels of IL-23 and IL-27 in culture supernatants before and after stimulation in healing form of disease was significantly higher than non-healing form (P < 0.001). Conclusion: It seems that IL-12 agonists might play a protection role in human leishmaniasis and further studies are needed to understand the role of these cytokine in cutaneous leishmaniasis.

Keywords

• Agonist
• IL-23
• IL-27
• Macrophages
• Promastigote
• Cutaneous leishmaniasis