Immunohistochemical identification of lymphocyte subsets and accessory cells in human hyperplastic lymph nodes. The functional significance of the compartmentalization of lymphoid tissue.

Biopsies from 21 lymph nodes with benign hyperplasia were examined by immuno-enzymatic labelling of frozen sections with a panel of monoclonal antibodies. B-cells (B1+, HLA-DR+, C3b receptor+/-) localized in primary follicles, secondary follicles, and areas adjacent to the subcapsular sinus. The B-cells in primary follicles and mantle zones of secondary follicles were indistinguishable ( SmIgD +, SmIgM +, CyIg -, T10-, CALLA-). B-cells adjacent to the subcapsular sinus demonstrated a higher density of SmIgM , and a weaker expression of SmIgD . The germinal centre cells showed a more differentiated phenotype ( SmIgD -, SmIgM +, CyIgM +/-), and also expressed T10 and CALLA. T-cells ( Lyt3 +, Lyt2+, Leu4 +, OKT6-, OKT10 -) localized in paracortial and interfollicular areas, and demonstrated a relative predominance of T-helper/inducer cells ( Leu3 +). T-helper/inducer cells were also identified in secondary follicles. The B-cell areas contained dendritic reticulum cells (R4/23+, C3b-receptor+). Interdigitating reticulum cells (HLA-DR+, OKT6+/-) localized in T-cell regions. The cells in sinuses demonstrated monocyte/macrophage properties (MO2+, Ig+, C3b-receptor+, HLA-DR+/-).