Scleritis (inflammation of sclera) is a strong indication of the underlying medical problem. It can be due to fungal, viral or parasitic infection, trauma, exposure to chemicals, poisonous gases or due to post-surgical complications.
Mast cells are granulated cells typically found in connective tissue. These cells mediate immune responses to foreign particles. In particular, they release large amounts of histamine and enzymes in response to antigen recognition.
Under microscopic examination, the secretory elements of the lacrimal gland are seen to be composed of serous acini cells partitioned into many lobules by loose connective tissues which contain many immune cells, mainly B-lymphocytes and plasma cells (most especially the IgA secreting cells).