Isolation and characterization of phytohemagglutinin-responsive, concanavalin A-nonresponsive human T lymphocytes.

Abstract

This chapter describes an experiment in which fractionated human tonsil lymphocytes are obtained by using buoyant density separation at 22°C using a 17–35% discontinuous bovine serum albumin gradient. From the experiment, it was found that tonsil contains a small subpopulation of T cells that respond to phytohaemagglutinin but not to con A. In this regard, they resemble mouse helper cell precursors but behave in marked contrast to mouse thymocytes, human thymocytes, and unfractionated peripheral lymphoid cells. The cells include the smallest, most dense, and slowest spontaneously dividing lymphocytes found in the tonsil.