UDC 616.379-008.64]:617.735-005-079-052:575

Abstract. Background. It is known that in diabetic retinopathy (DR), impaired transforming growth factor β1 (TGF-β1) signaling is accompanied by pathological angiogenesis, disruption of the blood-eye barrier, activation of inflammation and tissue fibrosis. The purpose of the study was to establish the relationship between the content of TGF-β1 in blood serum and intraocular fluid (IOF) and the progression of DR in type 2 diabetes mellitus (T2DM) using neural network modeling. Materials and methods. The study included the results of the examination of 102 people with T2DM, who were divided into 3 groups according to the stages of DR: the first one — non-proliferative DR (NPDR, 35 people), the second one — preproliferative (PPDR, 34 people) and the third one — proliferative (PDR, 33 people). The control group consisted of 61 individuals. The patients underwent standard ophthalmic examinations. TGF-β1 in blood serum and IOF was evaluated by enzyme-linked immunosorbent assay (Invitrogen Thermo Fisher Scientific, USA). Statistical analysis of the results was performed using the MedCalc software package (MedCalc SoftWare bvba, 1993–2013) and a two-layer neural network model with a linear postsynaptic potential function. Results. Using the genetic selection algorithm, 3 features were identified that were associated with DR: diabetes compensation and TGF-β1 content in blood and IOF. T2DM was compensated in 38 (37.3 %) patients, while in 64 cases (62.7 %), it was uncompensated. The proportion of the latter was higher in PDR than in NPDR and PPDR (p < 0.05). In PDR, the TGF-β1 content in IOF was significantly higher than in NPDR and PPDR (p < 0.05). A three-factor classification model was created on the identified features, which included a system of equations that predicted PDR with 100% accuracy. The overall prediction accuracy of the model was 88.2 % (95% CI 80.4–93.8 %). Conclusions. In this study, the value of indicators such as diabetes compensation and TGF-β1 content in serum and IOF for the progression of DR to PDR was shown using the method of neural network modeling. Keywords: proliferative diabetic retinopathy; diabetes mellitus; transforming growth factor β1; intraocular fluid; neural network modeling

Purpose: To study and compare the immune response and neopterin levels in the blood in experimental autoimmune uveitis (EAU).

Methods: A model of EAU was created in 30 Chinchilla rabbits. Intravenous and intravitreal injections of normal horse serum were administered for this purpose. Clinical examinations and blood tests were conducted on days 3, 7, 10, 14, and 21. The blood investigation included the determination of neopterin (NP) level, white blood cell counts, lymphocytes, CD3+ , CD4+ , CD8+ , and CD16+ .

Results: The peak in white blood cell count was observed on days 7 and 10 (6.4 ± 0.4 g/L and 6.0 ± 0.3 g/L, respectively), lymphocytes on day 3 (68.3% ± 2.4%, 3.0 ± 0.2 g/L), CD3 + on day 7 (64.9% ± 3.1%, 2,032.5 ± 91.2 cells/µL), CD4 + and CD16 + on day 10 (54.6% ± 3.8%, 2,462.3 ± 60.7 cells/µL and 21.8% ± 1.8%, 691.2 ± 37.1 cells/µL, respectively). All these values did not return to the initial ones. There was a gradual decrease in the CD8 + count from day 3 (12.5% ± 1.1%, 142.8 ± 9.1 cells/µL) with a subsequent gradual return towards normal levels by day 21. NP levels incresed on day 3 (5.2 ± 0.7 nmol/L), sustained on day 7 (5.2 ± 0.8 nmol/L), and started to decrease from day 10 (4.25 ± 1.7 nmol/L) to 2.3 ± 0.5 nmol/L on day 21. The highest correlation was observed between clinical manifestations and NP with a correlation coeffient of 0.799 (95% confidence interval, 0.719–0.858), which was significantly stronger (p < 0.05) than the correlations with other immune response markers. Conclusions: During the modeling of EAU, there is an active immune response and a rapid reaction of NP on inflammation. NP is a significantly more sensitive marker of intraocular inflammation than the immune response. It can serve as a predictor of the onset and development of EAU.

Key Words: Animal, Blood, Immunity, Neopterin, Uveitis

Aim: To investigate the dynamics of the T-cell immune response in rabbits with experimental autoimmune uveitis (EAU) of varying severity. Materials and Methods: The experiment involved two groups of Chinchilla rabbits (15 rabbits in each group). The model of EAU was created. The clinical picture of intraocular inflammation of varying severity was assessed. The determination of the level of white blood cells (WBC), lymphocytes (Lymphs), CD3+, CD4+, CD8+, and CD16+ in the blood of rabbits was conducted.

Results: Group I – moderate and severe uveitis, Group II – uveitis of mild severity. WBC, Lymphs, CD3+, CD4+, CD16+ were elevated and statistically significant in both groups of animals compared to control parameters on all days of the experiment (3, 7, 10, 14, 21 days) (p < 0.001). CD8+ level had a significantly lower count than the control one (p < 0.001). When comparing the two groups, the immune response was more active in Group I, and the number of immune cells did not return to normal by the end of the experiment.

Conclusion: In the case of EAU, the immune response is characterized by the activation of the T-cell immune system, with the intensity of this response depending on the severity of the clinical presentation of uveitis. Various degrees of clinical severity in EAU were obtained using an experimental model employed in our study. A rapid response of the immune system helps to establish a diagnosis and predict the severity of autoimmune uveitis.

Key words: T-cells response, experiment, autoimmune uveitis