Epstein-Barr virus LMP2A-induced B-cell survival in two unique classes of EmuLMP2A transgenic mice

J Virol. 2000 Feb;74(3):1101-13. doi: 10.1128/jvi.74.3.1101-1113.2000.

Abstract

Latent membrane protein 2A (LMP2A) is one of only two viral proteins expressed during latent Epstein-Barr virus (EBV) infections in human peripheral B cells. LMP2A blocks B-cell receptor (BCR) signal transduction in vitro by modulation of the Syk and Lyn protein tyrosine kinases. Five genetically unique LMP2A transgenic mouse lines (EmuLMP2A) with B-cell lineage expression of LMP2A were generated in this study to analyze the importance of LMP2A expression in vivo. These animals can be grouped into EmuLMP2A(BCR+) (TgB, Tg6, and TgC) and EmuLMP2A(BCR-) (Tg7 and TgE) lines based on B-cell phenotype. LMP2A expression in bone marrow cells of EmuLMP2A(BCR-) lines was associated with a bypass of normal B-lymphocyte developmental checkpoints inasmuch as immunoglobulin light-chain gene rearrangement occurred in the absence of complete immunoglobulin heavy-chain gene rearrangement. The resulting BCR-negative B cells were able to exit the bone marrow and colonize peripheral lymphoid organs. LMP2A expression in EmuLMP2A(BCR+) lines was not associated with altered B-cell development in a genetically wild-type background. When crossed into a recombinase activating null (RAG(-/-)) genetic background, LMP2A expression in either RAG(-/-) EmuLMP2A(BCR+) or RAG(-/-) EmuLMP2A(BCR-) animals was able to provide a survival signal to BCR-negative splenic B cells. Additionally, bone marrow cells from all EmuLMP2A animals were able to proliferate in response to interleukin-7-dependent developmental signals in vitro. These studies illustrate that LMP2A can provide a survival signal to BCR-negative B cells in two different groups of EmuLMP2A transgenic mice.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antigens, CD / metabolism
  • B-Lymphocytes / physiology*
  • Bone Marrow / metabolism
  • Cell Line
  • Cell Survival
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Immunoglobulin M / metabolism
  • Interleukin-7 / metabolism
  • Interleukin-7 / pharmacology
  • Leukopoiesis
  • Lymphoid Tissue / metabolism
  • Mice
  • Mice, Transgenic
  • Receptors, Antigen, B-Cell / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • T-Lymphocytes / physiology
  • Transcription, Genetic
  • Transgenes*
  • Viral Matrix Proteins / genetics*
  • Viral Matrix Proteins / metabolism*

Substances

  • Antigens, CD
  • DNA-Binding Proteins
  • EBV-associated membrane antigen, Epstein-Barr virus
  • Immunoglobulin M
  • Interleukin-7
  • Receptors, Antigen, B-Cell
  • Viral Matrix Proteins