High frequency of Epstein-Barr virus (EBV) lymphoblastoid cell line-reactive lymphocytes in cord blood: evaluation of cytolytic activity and IL-2 production

Clin Exp Immunol. 1997 Feb;107(2):312-20. doi: 10.1111/j.1365-2249.1997.258-ce1131.x.

Abstract

We investigated natural immunity towards autologous EBV lymphoblastoid cell lines (EBV-LCL) in the cord blood. Cord blood lymphocytes (CBL) from 20 healthy neonates were examined together with three EBV+ and one EBV- adult donors. We found that high frequencies of EBV-LCL-reactive cytotoxic lymphocytes, ranging from 1/190 to 1/12,205 were detectable in EBV- and EBV+ donors, as well as in the cord blood of 15 out of 20 neonates. Surface phenotype analysis, depletion experiments with MoAbs specific for T and natural killer (NK) lymphocyte subsets, and T lymphocyte cloning procedures strongly indicate virus-specific cytotoxic T lymphocytes (CTL) as the major population responsible for the lysis of autologous EBV-LCL in EBV+ donors. Conversely, a high frequency of NK cells seems to be involved in the killing activity observed in neonates and in the EBV- donor. Frequencies of EBV-LCL-induced IL-2-producing lymphocytes were high in EBV+ donors (range 1/2247-1/6633) and heterogeneous, but consistent, in cord blood (range 1/5072-1/57,819) and in the EBV- adult (1/17,148). CD8+ lymphocytes were responsible for IL-2 production in EBV+ individuals, while CD4+ T cells were charged with this role in cord blood and in the EBV- donor. These data demonstrate that CBL are able to develop a strong innate immunity, directed against autologous EBV-infected cells, mediated by both NK cells and CD4+ T lymphocytes. This characteristic may be relevant for protection against viral infections in both neonates and patients given cord blood transplantation (CBT).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • CD4-Positive T-Lymphocytes / metabolism
  • CD56 Antigen / analysis
  • Cell Line / virology
  • Fetal Blood / cytology*
  • Herpesvirus 4, Human / physiology*
  • Humans
  • Immunity, Innate
  • Infant, Newborn
  • Interleukin-2 / biosynthesis
  • Killer Cells, Natural / immunology
  • Lymphocytes / immunology
  • T-Lymphocytes, Cytotoxic

Substances

  • CD56 Antigen
  • Interleukin-2