Effect of Halococcus morrhuae and Halobacterium saccharovorum on the activation of human peripheral blood lymphocytes

The immunomodulator properties of two species of halophilic Archaebacteria, Halobacteriurn saccharovorum and Halococcus rnorrhuae, were analysed by th e study of lymphocyte activation. Two methods were used to detect activatio n in lymphocytes, namely incorporation of the radioactive nucleotide [H-3]- thymidine, and CD25 expression. H. morrhuae had a stimulatory effect on hum an lymphocytes, but this action was observed only with the [H-3]-thymidine uptake method, whereas H. saccharovorum produced no immunomodulator effect.