Expression of theta antigen on mouse thymocytes during the cell cycle.

Cells from normal mouse thymus were subdivided according to size and analysed for surface antigen expression, protein content and DNA expression and content. It could be shown, that the expression of theta-antigen followed protein accumulation in individual cells. Protein content on the other hand, was correlated with DNA synthesis even if it varied over a greater range. Only one subgroup of small non-DNA-synthesizing cells was calculated to have a higher density indicative of a more condensed state together with an increased surface antigen content. These cells might represent the G0 state of the remnant proliferating population and most resembled the small cortical cells.