Estimation of B- and T-Lymphocytes in Lymphoid Tissue by Means of Photometry and 51Cr Labelled Marker Erythrocytes

Abstract

Some new techniques for estimating B [bone marrow-derived]- and T [thymus-derived]-lymphocytes [human] in lymphoid tissue are introduced. The density of marker [sheep] erythrocytes on closed chamber incubated sections was estimated by the light transmission in relation to the number of the respective lymphocyte subpopulation, measured on suspensions of eluted lymphocytes. Using 51Cr labeled marker erythrocytes, the number of adsorbed marker erythrocytes per lymphocyte could be estimated from the .gamma.-irradiation of the section. The number of lymphocytes in the section was determined by the amount of protein in the section compared with the protein amount of a tissue specimen of known wet weight and known lymphocyte content. The number of adsorbed marker erythrocytes per rosette in suspensions of eluted lymphocytes was estimated by means of radioactively labeled marker erythrocytes.