Estudio inmunohistopatológico del bazo de ratones deplecionados de linfocitos t (cd4+ y cd8+) e infectados por chlamydophila abortus

Abstract

Several studies have stablished the innate immune response mechanisms against Chlamydophila abortus infection, but little is known about the role of the cellular immunity in C. abortus primary infection. The purpose of this work was to study the histopathological changes caused by C. abortus infection in the spleen in a murine intraperitoneal infection model in mice depleted of CD4+ T and/or CD8+ T cells. CD8+ T depleted mice showed 100% mortality rates at day 12 post infection (p.i.). In contrast, CD4+ T and CD4+ T /CD8+ T depleted mice showed no mortality rates at day 12 p.i. and morbidity was lower than that in non depleted control group. CD8+ T depleted mice and non depleted control mice showed a splenic parenchimal disorganization at day 6 p.i., and immunohistochemical C. abortus antigen detection revealed that all groups showed similar antigen distribution. CD8+ T depleted mice showed significant high rates of apoptosis. This results suggest that CD8+ T cells are essential for resolution of clamidial infection. The lack of this subpopulation leads to an exacerbate Th1 immune response caused by CD4+ T cells. CD8+ T cells could act as an immune regulatory subpopulation against C. abortus primary infection.