Abstract
Purpose: :
To determine the frequency of NK cells and CD4+IFNg+ T cells in patients with infectious corneal ulcers.
Methods: :
34 patients with infectious corneal ulcers were included in this study. Mononuclear cells were obtained from peripheral blood to determine CD3, CD4, CD8, CD19, CD56, CD69, Ki-67 and the intracellular cytokines IL-4, IFN-g on T cells, before and after policlonal stimulli. Data were analyzed by flow cytometry. Clinical features were evaluated to determine severity and correlated with the immunological findings. T test was used to compare statistical differences, p<0.05 was considered as statistically significant.
Results: :
We observed 1.3 times less frequently of CD56+ cells in patients with mycotic corneal ulcers (MCU) than in patients with bacterial corneal ulcers (BCU), and NK cells were 1.4 times less frequently in patients with MCU compared with viral corneal ulcers (VCU) patients (p=0.005). CD4+IFN-g+ T cells were 2 times diminished in patients with MCU than in patients with BCU (p=0.04). After polyclonal activation, we observed that the frequency of CD69+ cells was 1.7 times diminished in patients with MCU compared with BCU patients (p=0.02), and 2.6 times diminished in patients with MCU than in patients with VCU (p=0.003). Clinical severity was higher in patients with mycotic ulcers.
Conclusions: :
We observed diminished frequency of NK cells, CD4+IFNg+ T and CD69+ cells in patients with mycotic corneal ulcers, suggesting a deficient host immune response. It has been recognized that NK cells play an important role against fungi infection, interestingly we observed that patients with increased grade of severity were identified to be in the mycotic ulcers group.
Keywords: cornea: clinical science • keratitis • immunomodulation/immunoregulation