• Media type: E-Article
  • Title: Surfactant protein A inhibits T cell proliferation via its collagen-like tail and a 210-kDa receptor
  • Contributor: Borron, Paul; McCormack, Francis X.; Elhalwagi, Baher M.; Chroneos, Zissis C.; Lewis, James F.; Zhu, Sha; Wright, Jo Rae; Shepherd, Virginia L.; Possmayer, Fred; Inchley, Kevin; Fraher, Laurence J.
  • imprint: American Physiological Society, 1998
  • Published in: American Journal of Physiology-Lung Cellular and Molecular Physiology, 275 (1998) 4, Seite L679-L686
  • Language: English
  • DOI: 10.1152/ajplung.1998.275.4.l679
  • ISSN: 1522-1504; 1040-0605
  • Keywords: Cell Biology ; Physiology (medical) ; Pulmonary and Respiratory Medicine ; Physiology
  • Origination:
  • Footnote:
  • Description: <jats:p>Investigation of possible mechanisms to describe the hyporesponsiveness of pulmonary leukocytes has led to the study of pulmonary surfactant and its constituents as immune suppressive agents. Pulmonary surfactant is a phospholipid-protein mixture that reduces surface tension in the lung and prevents collapse of the alveoli. The most abundant protein in this mixture is a hydrophilic molecule termed surfactant-associated protein A (SP-A). Previously, we showed that bovine (b) SP-A can inhibit human T lymphocyte proliferation and interleukin-2 production in vitro. Results presented in this investigation showed that different sources of human SP-A and bSP-A as well as recombinant rat SP-A inhibited human T lymphocyte proliferation in a dose-dependent manner. A structurally similar collagenous protein, C1q, did not block the in vitro inhibitory action of SP-A. The addition of large concentrations of mannan to SP-A-treated cultures also did not disrupt inhibition, suggesting that the effect is not mediated by the carbohydrate recognition domain of SP-A. Use of recombinant mutant SP-As revealed that a 36-amino acid Arg-Gly-Asp (RGD) motif-containing span of the collagen-like domain was responsible for the inhibition of T cell proliferation. A polyclonal antiserum directed against an SP-A receptor (SP-R210) completely blocked the inhibition of T cell proliferation by SP-A. These results emphasize a potential role for SP-A in dampening lymphocyte responses to exogenous stimuli. The data also provide further support for the concept that SP-A maintains a balance between the clearance of inhaled pathogens and protection against collateral immune-mediated damage.</jats:p>
  • Access State: Open Access