Stimulation of canine lymphocyte subpopulations separated nonlytically by monoclonal anti-T and polyclonal Anti-B cell antibodies

Summary

Canine blood lymphocytes were nonlytically separated on antibody-coated petri dishes into surface immunoglobulin-positive (SIg⁺) and -negative (SIg⁻) populations. SIg⁻ cells were further separated into cells reactive or non-reactive with monoclonal antibody DT-2 recognizing canine T lymphocytes. The purity of the three enriched lymphocyte populations exceeded 90% as assessed by immunofluorescence.

Mitogen stimulation showed a vigorous response of SIg⁺ cells to pokeweed mitogen and concanavalin A but only a weak response to phytohemagglutinin. In mixed lymphocyte cultures, SIg⁺ cells were poor responders but potent stimulators. DT-2⁻ and DT-2⁺ cells responded to phytohemagglutinin, concanavalin A and pokeweed mitogen, and both populations were good responders in mixed leukocyte culture. Only DT-2⁻ cells were potent stimulators; DT-2⁺ cells were not. Hence, canine blood T cells can be divided into two subsets, DT-2⁺ and DT-2⁻, both of which are responsive to mitogens and alloantigens.