Purification of functional T lymphocytes from splenocytes of the beluga whales (Delphinapterus leucas)

In an effort to gain knowledge on immune functions in beluga whales, Delphi napterus leucas, we have used two physical methods for the purification of T lymphocytes of spleen cells. Isolation by sheep red blood cells (SRBC) ro setting and by adherence on nylon wool columns were tested. SRBC-rosetting gave unreliable results in obtaining purified T cells. Therefore, the purif ication of T cells was done using nylon wool columns. Less than 3% of the I gM(+) B cells remained in effluent populations. In the later population, 45 % gave positive staining with mouse anti-human CD4 allowing us to verify fu nctionality of the cells. The study of calcium mobilization and tyrosine ki nase activation, mediated by CD4 cross-linking permitted verification of th e functionality of cells. We also showed that upon activation wit mitogens, beluga T cells upregulate the density of MHC class II molecules on their s urfaces. CD4 cross-linking wit a specific antibody inhibited the proliferat ion response. Overall, the activation of beluga whales lymphocytes did not differ markedly from what is known in other species. This study can help in the groundwork for functional investigation of the beluga whale's immune s ystem. (C) 2000 Elsevier Science Ltd. All rights reserved.