The action of interferons on the morphology of mononuclear elements of human peripheral blood. S. E. M. observations

Scanning electron microscopy has been used to study the surface of lymphocytes and monocytes before and after treatment with interferon in vitro. Aliquots of peripheral blood isolated cells have been tested using either human leucocytic interferon (HuIFN-alpha) and human fibroblast interferon (HuIFN-beta) and both types combined. The investigation has been performed at various incubation times. The freshly isolated untreated lymphocytes exhibit a rough and villous surface. The smooth forms are uncommon. The treatment by various interferon types induces a new distribution of villous and rough structures as well as the forming of new elements called "uropods" and "pseudopods". At the same time, the binding of lymphocytic elements is enhanced by "cytoplasmic bridges" coming even to real "cellular fusions". Later, macrophages are also involved in these phenomena. These observations seem to confirm the hypothesis that the lymphocyte surface performs significant functions in detecting its surroundings and clearly underlines this cell capacity of reacting to specific substances such as interferons.