Histological and functional study of galectin-1 protein in murine model of type I allergic Conjunctivitis

Abstract

Galectin-1 (Gal-1) is a 14.5 kDa protein which controls the process of transmigration of leukocytes, cytokine release and degranulation of mast cells, contributing to the homeostasis of the inflammatory reaction. However, the expression of Gal-1 in normal and inflamed ocular tissues has been little studied. In this study we will evaluate the expression and mechanism of action of Gal-1 in an experimental model of allergic conjunctivitis (AC). Male Balb/c mice will be immunized on days 0 and 7, subcutaneously, with ovalbumin (OVA; 5 µg) and on days 14, 15 and 16, they will receive direct instillation into the conjunctival sac of OVA (250 µg) in 10 µl of sterile saline. Another group of sensitized animals will be pretreated intraperitoneally or by instillation with Gal-1 recombinant protein (rGal-1; 0.3 µg per animal) on days 14-16. Control group will receive only saline. After 4 and 24 hours of last OVA challenge, mice will be anesthetized for blood collection by cardiac puncture and then killed by cervical dislocation for removal of eyelids, eyes and peritoneal lavage. The studies will be conducted through: histopathological and quantitative analysis of mast cells and eosinophils in conjunctiva; levels of IgE and cytokines in the blood and in mouse eye lysates; and immunohistochemistry to detect the endogenous expression of Gal-1 and c-Jun N-terminal kinase (JNK) in palpebral conjunctiva and peritoneal cells. The results will contribute to better understanding of the role of Gal-1 in allergic ocular inflammation and provide new therapeutic options.