lymphocytes (T cells) play critical roles in the regulation of immune responses, and are responsible for mediating many of the effector mechanisms of the immune system. For this reason, there has always been a need for assays to measure accurately the activity of populations of T cells, both in model (animal) systems and in humans. The expansion of the biotechnology industry has led to a dramat...

Retroviruses can be classified according to the morphology of their virion core or according to sequence homologies that become evident after phylogenetic analyses. Human T-lymphotropic virus type 1 (HTLV-1) is a member of the deltatype retrovirus group, other members of which include HTLV types 2, 3 and 4, bovine leukaemia virus (BLV), and simian T-cell leukaemia virus (STLV) types 1, 2 and 3 ...

It has been recognized for more than half a century that, in addition to occasional mammary gland alveolar or ductal epithelial cell fragments, colostrum and milk consistently contain significant concentrations of viable leukocytes. These include lipid-laden macrophages that can exhibit ameboid and phagocytic activity, polymorphonuclear neutrophils, and lymphocytes of various sizes (1, 2). The ...