title: Spontaneous and cytokine-inducible 'natural' immunoglobulin secreting cells in organized lymphoid tissues of mice.
abstract: The number and frequency of spontaneous and cytokine-inducible 'natural' immunoglobulin-secreting cells (ISC) were determined in bone marrow (BM), spleen and Peyer's patch (PP), in vitro. Cells were cultured at limiting dilution in the presence or absence of exogenous recombinant cytokines and supernatants then assayed for total immunoglobulin (Ig) and Ig isotype using an ELISA. Most spontaneous ISC were found in the spleen and BM, with fewer in PP. The addition of recombinant interleukin 5 (rIL-5) promoted a marked increase in both the ISC frequency and the amount of Ig secreted/ISC whereas recombinant IL-6 (rIL-6) promoted only a marginal increase. Recombinant IL-4 (rIL-4) promoted a marginal increase in ISC frequency only. The isotype profile of ISC was in the order IgM greater than IgG2 greater than IgA greater than IgG3 greater than IgG1. The exposure of cells to 1200 rad of gamma-radiation resulted in decreased numbers of spontaneous ISC in all tissues, but the addition of rIL-5 or rIL-6 to the irradiated cells increased both the ISC frequency and Ig secreted. The Ig isotype profile was similar to that of non-irradiated ISC with a few minor exceptions. This large population of potential cytokine-inducible ISC could contribute to 'natural' Ig secretion in vivo.
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Australia.
authors.forename: R L
authors.initials: RL
authors.lastname: Kerlin
authors.forename: B L
authors.initials: BL
authors.lastname: Pike
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000502:physiology* / Q000528:radiation effects; D002478:Cells, Cultured / Q000502:physiology / Q000528:radiation effects; D005786:Gene Expression Regulation; D007132:Immunoglobulin Isotypes / Q000096:biosynthesis* / Q000187:drug effects; D015847:Interleukin-4 / Q000494:pharmacology; D015848:Interleukin-5 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology*; D008221:Lymphoid Tissue / Q000502:physiology* / Q000528:radiation effects; D051379:Mice; D008815:Mice, Inbred Strains; D010581:Peyer's Patches / Q000502:physiology; D011994:Recombinant Proteins / Q000494:pharmacology; D013047:Specific Pathogen-Free Organisms; D013154:Spleen / Q000502:physiology / Q000528:radiation effects
chemical_list: D007132:Immunoglobulin Isotypes; D015848:Interleukin-5; D015850:Interleukin-6; D007378:Interleukins; D011994:Recombinant Proteins; D015847:Interleukin-4