title: Priming of peripheral lymph node B cells with TNP-Ficoll: role of lymphokines in B cell differentiation.
abstract: We have previously shown that peripheral lymph node (PLN) B lymphocytes of adult DBA/2J mice failed to make an antibody response to type 2 antigen TNP-Ficoll, but exhibited a good antibody response to type 1 antigen TNP-Brucella abortus. In the present study we wanted to find out whether the unresponsiveness of PLN B cells to TNP-Ficoll is due to defects in the early activation and proliferation stage or in the final differentiation stage of B cells. Therefore, we have used a two-step protocol of in vivo immunization of mice with TNP-Ficoll and the subsequent in vitro challenge with TNP-Brucella abortus and studied the anti-TNP plaque-forming cell (PFC) responses. The results indicate a three- to sixfold increase of PFC responses in PLN cell cultures derived from TNP-Ficoll-primed animals compared to saline control mice. This increased antibody response was TNP-specific as 93% of the PFC's were inhibited by TNP-lysine. Limiting dilution experiments confirm that the increase in anti-TNP PFC response from the TNP-Ficoll-primed animals was indeed due to an increase in TNP-specific precursor B cells. Further, the addition of rIL-5 or rIL-6 induced anti-TNP PFC in the TNP-Ficoll-primed and in control PLN cell cultures in the presence of antigen. However, in primed PLN cells lymphokines alone were sufficient to restore anti-TNP PFC response. In conclusion, our results show that in PLN, the TNP-Ficoll can induce proliferation of hapten-specific B cells but not final differentiation. These primed PLN B cells mature into antibody-secreting cells upon stimulation with TNP-BA or lymphokines.
authors.affiliation: Department of Microbiology and Immunology, University of Kentucky, Lexington 40536.
authors.forename: S N
authors.initials: SN
authors.lastname: Goud
authors.forename: A M
authors.initials: AM
authors.lastname: Kaplan
authors.forename: B
authors.initials: B
authors.lastname: Subbarao
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D005362:Ficoll / Q000031:analogs & derivatives* / Q000276:immunology; D007114:Immunization; D007378:Interleukins / Q000502:physiology*; D008198:Lymph Nodes / Q000276:immunology*; D051379:Mice; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011994:Recombinant Proteins / Q000494:pharmacology; D014301:Trinitrobenzenes / Q000276:immunology*
chemical_list: D007378:Interleukins; D011994:Recombinant Proteins; C020529:TNP-ficoll; D014301:Trinitrobenzenes; D005362:Ficoll