CD4+ and CD8+ t lymphocyte counts and ratio in cats with chronic gingivostomatitis and naturally infected with feline immunodeficiency virus: a preliminary study

Abstract

This study aimed to evaluate the CD4⁺ and CD8⁺ T lymphocytes counts and CD4⁺: CD8⁺ ratio in a colony of cats with chronic gingivostomatitis (CGS). We used forty domestic short-haired cats inhabiting the same colony. Ten cats with CGS were immunodeficiency virus-positive (group IV), and ten with CGS were immunodeficiency virus-negative (group III). As a control, twenty cats without CGS were used: ten cats were immunodeficiency virus-positive and (group II) and ten cats were immunodeficiency virus-negative (group I). We employed flow cytometry to count CD4⁺ and CD8⁺ T lymphocytes. In FIV-infected cats, the presence of CD4⁺ lymphocytes were lower both for animals with and without CGS. Conversely, non-FIV-infected cats with CGS had a higher amount of CD4⁺ when compared to seronegative animals without CGS. The counts of CD8⁺ T lymphocytes showed no significant difference among cats with CGS, whether infected with FIV or not. The CD4⁺: CD8⁺ ratio was only different for group III, which was higher than any other group. No difference was observed for total lymphocyte number and CD8⁺ among groups. By contrast, mean CD4⁺ levels were different, with cats from groups III and IV showing higher levels than those from groups I and II. The flow cytometry could be a useful tool for the diagnosis and prognosis of cats with CGS infected by the immunodeficiency virus.