Phenotypic and functional characterization of a panel of cytotoxic murine NK cell clones that are heterogeneous in their enhancement of Ig secretion in vitro.
NK cells not only function as cytotoxic effector cells, but also have immunoregulatory roles including the enhancement of Ig secretion. To have a stable and uniform population of NK cells to study their role in Ig secretion, we generated murine NK clones. Thus, culture of splenocytes from mice that were homozygous for a mutation in the p53 tumor suppressor gene (p53-KO) with IL-2 and poly(IC) resulted in a long-term NK line, from which four stable clones were derived. This approach also yielded a long-term NK line from splenocytes of normal C57BL/6 mice. Identification of the clones as members of the NK lineage was based on large granular morphology, expression of NK-TR and absence of TCR gene rearrangement. Flow cytometry revealed that all clones expressed IL-2R alpha and beta, chains and B220, but no CD3, NK1.1, DX5 or Ly-49. RT-PCR analysis showed heterogeneity in NK1.1 gene expression, and demonstrated expression of perforin and several granzymes in all clones. Three out of four clones lysed YAC-1, but not P815 target cells, corresponding to a pattern of NK specificity. All NK clones enhanced Ig secretion in an in vitro model for T cell-independent type 2 antigens, albeit to varying degrees. We found no correlation between the degree of helper activity of the NK clones and the level of their cytotoxic activity on YAC-1 targets. Thus, we established murine NK clones, and show that they mediate both cytotoxicity and enhancement of Ig secretion.
Vos
Q
Q
Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Ortaldo
J R
JR
Conan-Cibotti
M
M
Vos
M D
MD
Young
H A
HA
Anderson
S K
SK
Witherspoon
K
K
Prager
I
I
Snapper
C M
CM
Mond
J J
JJ
D000818:Animals; D000941:Antigens / Q000032:analysis / Q000235:genetics; D015703:Antigens, CD / Q000032:analysis; D000950:Antigens, Ly; D000954:Antigens, Surface; D001402:B-Lymphocytes / Q000276:immunology; D001798:Blood Proteins / Q000235:genetics; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D019674:Genes, T-Cell Receptor beta / Q000235:genetics; D007075:Immunoglobulin M / Q000032:analysis / Q000096:biosynthesis*; D007694:Killer Cells, Natural / Q000276:immunology*; D037181:Lectins, C-Type; D017493:Leukocyte Common Antigens / Q000032:analysis; D008562:Membrane Glycoproteins / Q000032:analysis / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D018345:Mice, Knockout; D055651:NK Cell Lectin-Like Receptor Subfamily B; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D011506:Proteins / Q000032:analysis / Q000235:genetics; D015375:Receptors, Interleukin-2 / Q000032:analysis; D055630:Receptors, NK Cell Lectin-Like; D055607:Receptors, Natural Killer Cell; D012697:Serine Endopeptidases / Q000235:genetics; D013154:Spleen / Q000276:immunology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
D000941:Antigens; D015703:Antigens, CD; D000950:Antigens, Ly; D000954:Antigens, Surface; D001798:Blood Proteins; D007075:Immunoglobulin M; C527211:Klrb1c protein, mouse; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D055651:NK Cell Lectin-Like Receptor Subfamily B; D052899:Pore Forming Cytotoxic Proteins; D011506:Proteins; D015375:Receptors, Interleukin-2; D055630:Receptors, NK Cell Lectin-Like; D055607:Receptors, Natural Killer Cell; D016159:Tumor Suppressor Protein p53; D054353:Perforin; D017493:Leukocyte Common Antigens; D012697:Serine Endopeptidases