Importance of immunomodulation in trachoma-related tissue damage and tear function disorders

Abstract

To put forward better prevention and treatment strategies in trachomatous tissue damage and tear function disorders, a field survey was performed in a village in the province of Turkey, which is a settlement with endemic trachoma according to the World Health Organization. Samples of tears, upper tarsal conjunctiva, and serum were taken from patients with 5 different stages of trachoma, including 13 patients in the initial stage and 15 in each of the other stages. Samples were also collected from 15 healthy control patients. We measured the levels of interleukin (IL)-1, IL-2, epidermal growth factor (EGF), and tumor necrosis factor (TNF) using enzyme-linked immunosorbent assays (ELISAs). We measured immunoglobulin M (IgM), IgA, and IgG levels in tears using immunodiffussion plates. EGF, human leukocyte antigen – antigen D related (HLA-DR), and interleukin -2 receptor (IL-2R) expression, and lymphocyte and monocyte infiltration were examine d using direct immunofluorescence of upper tarsal conjunctiva samples. Antichlamydial IgM, IgA, and IgG serum levels were also measured. The distribution of trachoma in this residential area and its complications according to age and genders were determine d using additional field scans. Data analysis revealed that the significant increase in the levels of neutrophils, IL -1, TNF, and cytotoxic T lymphocytes, which are the indicators of nonspecific immune response in the early stages of trachoma, results in suppression/dominance of IL-2, IL-2R, HLA-DR, helper T cells, and 13 lymphocytes and immunoglobulins as the disease progresses. EGF increases to very high levels in later stages.