Suppression of immune responsiveness by a submandibular salivary gland factor.

Both tissue extracts prepared from submandibular salivary glands of male mice and epidermal growth factor isolated from these glands depressed the delayed type hypersensitivity response to 2,4-dinitro-1-fluorobenzene in mice. Extirpation of the submandibular salivary glands from male mice did not alter the delayed type hypersensitivity response. The role of salivary gland factors, particularly epidermal growth factor, in influencing the immune response has been discussed.