The Role of CD4+ and CD8+ T-Cells during Angiostrongylus vasorum Infection in Dogs

Abstract

A determinant factor in the pathology of canine angiostrongylosis seems to be related to the location of the parasite in the definitive host. Their presence inside the arteries and its branches, promoting mechanical and metabolic action on the wall of the vessels, may alter its homeostasis. Bronchoalveolar lavage (BAL) is a procedure that retrieves cells and other elements from de lungs for evaluation, and helps in the diagnosis of many pulmonary diseases. The aim of this study was to evaluate CD4+/CD8+ lymphocyte profile during the infection by Angiostrongylus vasorum, using cells retrieved using BAL. The identification of subpopulations of T lymphocytes by evaluating the co-expression of CD4 and CD8 receptor proteins has shown that despite the increase in both populations, there was a predominance of CD4+ T-cells, instead of CD8+ T-cells. These increases of CD4+ T-cells associated with the increase of the ratio between CD4+/CD8+ suggest polarization of a Th2 response. However, the immune cells, signaling factors, and cytokines that mediate such immunity and how and where they act within the body remain largely undefined during angiostrongylosis.