Clinical significance of assessing the subpopulation composition of blood lymphocytes in patients with infectious corneal lesions in high-risk keratoplasty

The purpose is to study the shifts in the subpopulation composition of blood lymphocytes in patients with infectious corneal lesions, depending on the number of keratoplasties (KP) undergone by the patient. Material and methods. We examined 53 patients (aged 18 to 79) with infectious keratitis, divided into three groups, depending on the number of KP: group I (n = 27) with no KP; groups II (n = 12) who underwent one KP; group III (n = 14) who has two or more KPs. The control group consisted of 33 apparently healthy donors. The relative and absolute content of subpopulations of T lymphocytes (CD3+), T helper cells (CD3+CD4+CD8-), T cytotoxic cells (CD3+CD4-CD8+), double positive T lymphocytes (CD3+CD4+CD8+), NK cells (CD16+CD56+), and B lymphocytes (CD19+) was determined using flow cytometry, the CD4+/CD8+ index was calculated. Results. The analysis of the total population of T lymphocytes and the CD3+CD4+ subpopulation showed a significant increase in the absolute number of T lymphocytes in group II (CD3+: 1.77 ± 0.10 × 10 9 /l; T helpers: 1.02 ± 0.09 × 10 9 /l) as compared to group I (1.44 ± 0.06 × 10 9 /l and 0.85 ± 0.03 × 10 9 /l, respectively). In group III, there was a substantial significant increase in the relative amount of CD3+CD4+(50.1 ± 1.9 %) as compared to groups without KP (I: 43.2 ± 1.5 %) and one surgery group (II: 43.3 ± 1.8 %), which led to a significant increase in the ratio of CD4+/CD8+ in group III (2.16 ± 0.19). In the blood of all patients (group I: 0.020 ± 0.003 × 10 9 /l; II: 0.030 ± 0.002  10 9 /l; III: 0.030 ± 0.001  10 9 /l) a significant increase in the absolute number of double positive T lymphocytes (CD3+CD4+CD8+) as compared to the control (0.009 ± 0.007  10 9 revealed. Conclusion. The changes revealed in the cellular component of the immune status, common for all patients were characterized exclusively by shifts in the T link of immunity. Individual analysis of the nature of shifts of T helper cells and CD4+/CD8+ going upward from the norm allowed us to qualitatively identify group III (with two or more KPs). The obtained data are important for the development of the criteria for predicting high-risk keratoplasty and confirm that Clinical significance of assessing the subpopulation composition of blood lymphocytes in patients with infectious corneal lesions in high-risk keratoplasty