Autocrine growth of human B lymphocytes: maintained response to autostimulatory factors is the special feature of immortalization by Epstein-Barr virus--a hypothesis.
The autocrine growth profile of human B lymphocytes transformed with Epstein-Barr virus (EBV) was found to comprise three distinct components: a B-cell growth factor (BCGF); an interleukin-1 (IL-1)-like activity; an activity requiring cell-to-cell contact for its action. Observations on the inhibition of the EBV-carrying Daudi lymphoma line by alpha-interferon indicated that loss of response to these autostimulatory factors was underlying growth cessation. Furthermore, a putative receptor for BCGF was found to be down-regulated on B cells stimulated with non-transforming mitogens but constitutively expressed following EBV-transformation. Taken together with recent evidence that normal B cells produce autostimulatory factors, these findings suggest that the special feature of autocrine growth by EBV-immortalized cells is a maintenance of what should normally be a transient phenotype, possibly through deregulation of receptor expression. This hypothesis is discussed.
D001402:B-Lymphocytes / Q000166:cytology / Q000382:microbiology*; D002450:Cell Communication; D002455:Cell Division; D002472:Cell Transformation, Viral; D006133:Growth Substances / Q000032:analysis; D004854:Herpesvirus 4, Human; D006801:Humans; D007375:Interleukin-1 / Q000032:analysis; D015847:Interleukin-4; D007700:Kinetics; D008222:Lymphokines / Q000032:analysis; D008970:Molecular Weight; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000032:analysis
D006133:Growth Substances; D007375:Interleukin-1; D008222:Lymphokines; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D015847:Interleukin-4