‘L’ lymphocytes, immune complexes and the amplification of human T lymphocyte proliferation

  • D. A. Horwitz
  • E. M. Carvalho
Part of the Inflammation: Mechanisms and Treatment book series (FTIN, volume 4)


Immune complexes have an important role in the regulation of the immune response. IgG complexed to specific antigen can enhance or suppress lymphocyte proliferation in vitro. We have focussed our attention on augmentation of lymphocyte proliferation and have described the conditions required for enhancement by immune complexes, identified the lymphocyte population mediating this effect and have described a mechanism of action1,2. These studies will be summarized in this report. We will show that ‘L’ lymphocytes amplify T cell proliferation. ‘L’ lymphocytes are the C3 receptor negative sub-set of non-T non-B cells and comprise approximately 10% of blood lymphocytes in healthy individuals. The surface markers and functional properties of L cells have been well characterized3,4.


Immune Complex Lymphocyte Proliferation Keyhole Limpet Haemocyanin Unstimulated Culture Lymphocyte Blastogenesis 
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Copyright information

© MTP Press Limited 1980

Authors and Affiliations

  • D. A. Horwitz
    • 1
  • E. M. Carvalho
    • 1
  1. 1.USA

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