Effect of cell-derived growth factors and cytokines on the clonal outgrowth of EBV-infected B cells and established lymphoblastoid cell lines.
Epstein-Barr virus (EBV) is a potent inducer of polyclonal B lymphocyte proliferation and is widely used as a tool for the establishment of B cell lines producing human monoclonal antibodies. However, because of low transformability, low clonability, and the inherent instability of EBV-infected B cells, valuable antibody-producing B cells are often lost during this procedure. We have here examined various cell-derived cytokines for their ability to enhance both the cellular outgrowth of newly infected B cells and the clonability of infected B cells and lymphoblastoid cell lines. Our results show that the murine thymoma cell line EL-4 is superior to peripheral blood mononuclear cells in both cellular outgrowth and cloning experiments, whereas monocyte-derived factors and monocyte cell lines were less capable than peripheral blood mononuclear cells in enhancing cellular outgrowth and cloning. Furthermore, the human T cell hybridoma cell line MP6 that secretes a B cell growth and differentiation factor, recently identified as an isoform of thioredoxin, is also capable of stimulating EBV-infected B cells and lymphoblastoid cell lines. Co-cultivation of EBV-infected B cells with MP6 cells significantly enhanced the cloning efficiency at the 1 cell/well level. The present results also suggest that one potential role of the MP6-derived thioredoxin could be the up regulation of IL-6 receptor expression in EBV-infected B cells.
Ifversen
P
P
Department of Immunotechnology, Lund University, Sweden.
Zhang
X M
XM
Ohlin
M
M
Zeuthen
J
J
Borrebaeck
C A
CA
D001402:B-Lymphocytes / Q000187:drug effects / Q000382:microbiology / Q000502:physiology*; D002460:Cell Line; D002461:Cell Line, Transformed; D002472:Cell Transformation, Viral; D016207:Cytokines / Q000494:pharmacology*; D004247:DNA / Q000096:biosynthesis; D006133:Growth Substances / Q000494:pharmacology*; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects*; D011971:Receptors, Immunologic / Q000032:analysis; D019947:Receptors, Interleukin-6; D013879:Thioredoxins / Q000494:pharmacology
D016207:Cytokines; D006133:Growth Substances; D011971:Receptors, Immunologic; D019947:Receptors, Interleukin-6; D013879:Thioredoxins; D004247:DNA