title: Morula forms of E rosettes: distribution, specific inhibition, and enhancement.
abstract: Rosetts-forming cells (RFC) with more than 10 sheep red blood cells (SRBC's) per cell defined as morula-forming cells (MFC) were studied in human lymphoid organs and in the peripheral blood (PBL). MFC are most common in the thymus (more than 50%) and the frequency is much less in peripheral lymphoid tissues and in the blood (29.8% in those less than 5 years old; 14.9% in adults). There is very slight decrease in total RFC in PBL over age 5, but the changes in MFC are quite striking. Treatment with antihuman thymus antiserum (ATS) and with anti-human lymphoblastic antiserum (ATL) resulted in significant inhibition of total rosette and morula rosette formation. No inhibition was seen using normal brain antiserum, anti-IgM antiserum, or anti-L chain antiserum. In two patients with chronic lymphocytic leukemia and in some cases of thymic deficiency the ratio of MFC to total RFC was unusually high. After culture with phytohemagglutinin (PHA) and conversion to blast forms or after surface peturbation by papain or freeze-thaw treatment, MFC numbers were increased.
mesh_terms: D006801:Humans; D007104:Immune Adherence Reaction; D007106:Immune Sera; D008221:Lymphoid Tissue / Q000166:cytology* / Q000276:immunology; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D013601:T-Lymphocytes / Q000166:cytology*
chemical_list: D007106:Immune Sera