The cell surface antigen and DNA content distribution of lymph nodes with reactive hyperplasia
Maiese, R.L.; Segal, G.H.; Iturraspe, J.A.; Braylan, R.C.
Modern Pathology An Official Journal of the United States and Canadian Academy of Pathology Inc 8(5): 536-543
1995
ISSN/ISBN: 0893-3952 PMID: 7675774 Document Number: 454392
Few studies have comprehensively examined the expression and distribution of cell surface antigens and DNA content in non-neoplastic, reactive lymph nodes. We have performed a flow cytometric immunophenotypic and DNA content analysis of 64 lymph nodes from 62 patients (23 male; 39 female; ages 21 months to 80 years) with typical reactive lymphoid hyperplasia as assessed by histology. CD45, a pan-leukocyte marker, was detected on virtually all cells (99 +- 4%). All pan-T-cell-associated antigens studied were expressed within a narrow range of average values (54-64%), and no loss of individual T-cell antigens was observed in any case. Intercase variation of fluorescence intensity for each antigen was minimal. The mean CD4:CD8 ratio was 3.9 +- 2.6, with only one case (HIV+) showing a marked CD4:CD8 inversion (0.4). The number of cells coexpressing CD4 and CD8 was very low (3 +- 3%), consistent with the mature phenotypic nature of the majority of T lymphocytes. B-cells, as defined by CD19 and CD20 antibodies, accounted for 36 +- 16% and 43 +- 18% of cells analyzed, respectively, and, like the pan-T-cell antigens, displayed minimal intercase variability in antigen expression. Cells coexpressing CD20 and CD5 were noted, although their frequency could not be calculated accurately. IgD- and IgM-bearing cells were both generally well-defined populations: 24 +- 10% and 31 +- 14%, respectively. On the other hand, IgG- and IgA-bearing cells displayed broad fluorescence intensity, precluding an exact calculation of their frequencies. To avoid counting non-B-cells with nonspecifically bound immunoglobulin, kappa and kappa immunoglobulin light chains were analyzed on B-cells exclusively, selected by CD20 or CD 19 antibodies. The values for kappa and lambda, expressed as percentages of CD20-positive cells, were 55 +- 7% and 41 +- 5%, respectively. Essentially identical results were obtained when kappa and lambda were analyzed on CD19-expressing cells. The mean kappa:lambda ratio was the same for CD20 and CD19-selected cells (1.4 +- 0.3). CD10 (CALLA) was observed on an average of 4 +- 6% of all cells analyzed. The myeloid-associated antigens CD13 and CD33 were found on less than 4% of cells. CD14, a monocyte marker, and natural killer cell-associated markers CD16 and CD56 were each detected on a small fraction of cells. The stem cell-associated antigen CD34 was essentially absent (0 +- 1%). CD11c, CD71, CD23, and HLA-DR were expressed with variable intensity but did not label discrete cell subpopulations. All cases were found to be diploid by DNA content analysis. Proliferative activity, as evidenced by S-phase fraction determinations, was found to encompass a range of 0.2-14.0%, with a mean value of 3.0 +- 2.8%. This extensive quantitative and qualitative description of the leukocyte surface marker distribution and DNA content of reactive lymph nodes should serve well as a reference for studies of neoplastic lymphoid processes.