Interleukin 1- and 2-like activities in the dog.

Canine adherent and non-adherent peripheral blood leukocytes and spleen cells were examined for their ability to produce soluble factors with Interleukin 1- and 2- (IL-1 and IL-2) like activities. For this purpose, three conventional assay systems were used: (a) proliferation on an IL-2-dependent murine cytotoxic T-lymphocyte cell line, (b) enhancement of PHA-induced murine thymocyte proliferation and (c) proliferation of lectin-primed canine peripheral blood lymphocytes (PBL). Only the latter two types of cells respond to IL-1, whereas all three types respond to IL-2. Both types of factors were produced and the kinetics of their release/production were found to be identical to those of human PBL. Results suggested that species-related differences existed. Canine interleukin-containing supernatants had higher titers than murine interleukin-containing supernatants when analyzed on canine lymphocytes, and the reverse was found if murine target cells were used.