Mechanism of Hypergammaglobulinemia by HIV Infection: Circulating Memory B-cell Reduction With Plasmacytosis

Clin Immunol. 2001 Aug;100(2):250-9. doi: 10.1006/clim.2001.5054.


The mechanism of hypergammaglobulinemia in patients infected with HIV has remained unclear in spite of the identification of a reduction of CD4+ T cells. The amounts of CD27+ memory B cells were remarkably reduced in the peripheral blood and immunoglobulin (Ig) production was diminished in HIV-infected patients. Some of the freshly isolated patients' T cells expressed the CD70 (CD27 ligand) on the surface and the CD70 expression on both of the CD4+ and CD8+ T cells was greatly enhanced by various stimuli. It was also striking that plasmacytosis was observed in patients' bone marrow. Thus, our findings suggest that CD70 expressed spontaneously or by activation on T cells of HIV-infected patients stimulates memory B cells via CD27 and promotes their differentiation into plasma cells, resulting in the elevation of serum Ig levels and the elimination of circulating memory B cells in HIV-infected patients.

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Antigens, CD*
  • B-Lymphocytes / immunology*
  • CD27 Ligand
  • Child, Preschool
  • Female
  • HIV Infections / complications
  • HIV Infections / immunology*
  • Humans
  • Hypergammaglobulinemia / complications
  • Hypergammaglobulinemia / immunology*
  • Male
  • Membrane Proteins / immunology
  • Middle Aged
  • Molecular Sequence Data
  • Plasma Cells / immunology*
  • Tumor Necrosis Factor Receptor Superfamily, Member 7 / immunology


  • Antigens, CD
  • CD27 Ligand
  • CD70 protein, human
  • Membrane Proteins
  • Tumor Necrosis Factor Receptor Superfamily, Member 7