Subclass of individual IgA-secreting human lymphocytes. Investigation of in vivo pneumococcal polysaccharide-induced and in vitro mitogen-induced blood B cells by monolayer plaque-forming cell assays

J Immunol. 1988 Mar 1;140(5):1496-9.

Abstract

The subclass of individual human IgA B cells was investigated by means of monolayer plaque-forming cell assays permitting analysis of all IgA-secreting cells as well as of cells secreting IgA anti-pneumococcal polysaccharide antibody. Center cells were examined by indirect immunofluorescence staining with mouse mAb against either of the two IgA subclasses as primary antibodies and FITC-conjugated rabbit anti-mouse Ig as the second antibody. Blood lymphocytes spontaneously secreting IgA (mean 399/10(6) mononuclear cells) produced mainly IgA1 (73%). A similar distribution of subclasses was recorded among IgA-secreting blood cells in PWM- and EBV-stimulated cultures. In contrast, a predominance of IgA2 (54%) was found among IgA-secreting cells (2531/10(6)) isolated from the blood 7 days after in vivo stimulation with pneumococcal polysaccharides, and a similar proportion (51%) of IgA2 producing cells was found among IgA anti-pneumococcal polysaccharide-secreting cells. It was thus confirmed that IgA1 is the predominant subclass of blood IgA-secreting cells in general. However, the high percentage of IgA2-secreting cells found after vaccination with pneumococcal polysaccharides suggests that these Ag have an unusually high ability to activate IgA2 B cells, or that the B cells stimulated originate from lymphatic tissues with a high frequency of IgA2 committed cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibody Specificity
  • B-Lymphocytes / classification*
  • B-Lymphocytes / immunology
  • B-Lymphocytes / metabolism
  • Bacterial Vaccines / administration & dosage*
  • Binding Sites, Antibody
  • Hemolytic Plaque Technique*
  • Herpesvirus 4, Human
  • Humans
  • Immunoglobulin E / biosynthesis*
  • Immunoglobulin E / classification
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / metabolism
  • Lymphocyte Activation*
  • Middle Aged
  • Pneumococcal Vaccines
  • Pokeweed Mitogens
  • Streptococcus pneumoniae / immunology*

Substances

  • Bacterial Vaccines
  • Pneumococcal Vaccines
  • Pokeweed Mitogens
  • Immunoglobulin E