[Cellular immunity in patients with diabetes mellitus complicated by diabetic retinopathies].

A total of 200 patients with diabetes mellitus were examined for T and B immunity systems. The T and B lymphocytes were counted, the response of T lymphocytes to PHA and their sensitivity to thymosine and theophylline were determined. The data obtained attest to inhibition of the T immunity system in patients with diabetes mellitus regardless of the ophthalmoscopic appearance of the eye fundus, with this inhibition being most remarkable in subjects without vascular lesions of the retina. Patients with proliferating diabetic retinopathy manifested activation of the B cell component of immunity. Changes in the content and function of T lymphocytes were followed by inhibition of the hormonal activity of the thymus and accumulation in the blood of the theophylline-sensitive T cell population. It is suggested that quantitative and qualitative deficiencies of cellular immunity give rise to the development of immune complex pathology resulting in the formation and progression of diabetic retinopathies.