title: Plaque formation by B cell colonies.
abstract: A method is described for routinely detecting secretion of antibodies by intact B cell colonies grown in soft agar. Protein A-coupled sheep red blood cells and hapten-conjugated sheep red blood cells were found to be suitable targets. Using this assay we have determined that approximately 1 in 3 B cell colonies contain cells secreting IgM while approximately 1 in 6 contain cells secreting IgG. We have also determined the frequency of clones which secrete antibodies which lyse TNP3-SRBC, NIP4-SRBC, NP4-SRBC, FITC5-SRBC, SRBC, and HRBC. This assay can be used to study the mitogen-induced maturation of clonable B cells into plaque-forming cells, to follow antigen-specific clonable B cells during an immune response, and unambiguously to detect B cell colonies when other colony types are present. The method is also suitable for morphological analysis of stained colony cells.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002469:Cell Separation / Q000379:methods*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D006462:Hemolytic Plaque Technique; D007075:Immunoglobulin M / Q000096:biosynthesis; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D013997:Time Factors
chemical_list: D007075:Immunoglobulin M; D003513:Cycloheximide