, Volume 5, Issue 1, pp 193–202

Specific immunorecognition by histocompatibility markers: The original polymorphic system of immunoreactivity characteristic of all multicellular animals

  • William H. Hildemann

DOI: 10.1007/BF01570476

Cite this article as:
Hildemann, W.H. Immunogenetics (1977) 5: 193. doi:10.1007/BF01570476


The existence of two immunorecognition systems, theH system of cell-mediated immunity and theIg system of antibody-mediated immunity, is proposed. TheH system, based on polymorphism of cell-surface histocom-patibility markers, is postulated to have originated in multicellular invertebrates, probably beginning with coelenterates. Subsequent differentiation and diversification of immunocytes, associated with increasing physiological complexity in phylogeny, are postulated to have led to the addition of a regulatoryIg system at the level of primitive chordates or fishes. Progressive integration of theH andIg systems then provided T-B lymphocyte collaboration and the immunoregulatory network characteristic of higher vertebrates. Experimental tests are suggested for the hypothesis of a two-component system of specificH-marker immunorecognition, leading to nonspecific cytotoxic reactions mediated by nonantibody proteins.

Copyright information

© Springer-Verlag New York Inc. 1977

Authors and Affiliations

  • William H. Hildemann
    • 1
  1. 1.University of California Schools of Medicine and DentistryLos Angeles