Immunology of Leishmaniasis

TLDR: The role of the immune response to Leishmania, with particular reference to the cutaneous disease caused by L. major, is discussed, and the concept of suppressor T cells is reviewed.

Abstract: Publisher Summary This chapter discusses the role of the immune response to Leishmania, with particular reference to the cutaneous disease caused by L. major. Leishmaniasis is caused by species of the intracellular protozoan parasite belonging to the genus Leishmania. There are three main categories of leishmaniasis: cutaneous leishmaniasis (oriental sore), mucocutaneous leishmaniasis (espundia), and visceral leishmaniasis (kala-azar). In humans, infection with Leishmania results in a spectrum of disease dependent upon the species involved and the efficiency of the host's immune response to the parasite. Diagnosis of active leishmaniasis is based primarily on the demonstration of the parasite in biopsies. A skin test using a killed whole parasite preparation (leishmanin) is used as a presumptive test. Genetic regulation of leishmaniasis is discussed in reference to mouse and humans, and the concept of suppressor T cells is reviewed. The various cytokines in leishmaniasis, including interferon (IFN) γ and interleukin (IL)-4, IL-10, IL-1, and IL-2 are also discussed.