Abstract
Since 1970 a simple whole-blood macroculture system has been used to give an accurate and reproducible test for cellular immunity. The present work was designed to develop a simple but flexible whole-blood micro-assay for use in diagnostic tests. A comprehensive test of immunocompetence may be carried out using this simple assay on small blood volumes (0.25 ml), obtained from finger-prick samples in heparinised tubes. The presence of granulocytes and erythrocytes provides an optimal environment for in vitro lymphocyte culture and gives culture conditions which are more stable and resistant to contamination than purified lymphocyte cultures. This whole-blood microculture has been used to identify natural immunosuppression and reduced lymphocyte responses due to therapy.