Low erythrocyte complement receptor type 1 (CR1, CD35) expression in preeclamptic gestations

Am J Reprod Immunol. 2005 Dec;54(6):352-7. doi: 10.1111/j.1600-0897.2005.00318.x.


Problem: Erythrocyte complement receptor type 1 (E-CR1) is the main immune complex clearance mechanism in humans. Decreased E-CR1 expression is noted in certain inflammatory disorders. Recent evidence implicates inflammation in the pathogenesis of preeclampsia. We investigated whether E-CR1 is decreased in preeclampsia.

Method of study: E-CR1 protein expression was quantified by radioimmunoassay. Plasma concentration of soluble CR1 was quantified using a specific enzyme linked immunosorbent assay. Quantitative genotypes were evaluated by HindIII restriction fragment length polymorphism analysis.

Results: E-CR1 expression was reduced in patients with preeclampsia. Lack of neoantigen expression (indicative of enzymatic cleavage of CR1) or elevated plasma-soluble CR1 was evidence against an acquired loss of E-CR1. Genotype analysis revealed a higher frequency of a CR1 allele associated with low E-CR1 expression in preeclampsia when compared with normal pregnant controls.

Conclusions: E-CR1 expression is decreased in preeclamptic patients and levels correlate with severity of disease. This condition may have a genetic basis in some patients.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Erythrocytes / immunology*
  • Erythrocytes / metabolism
  • Female
  • Humans
  • Peptide Hydrolases / immunology
  • Peptide Hydrolases / pharmacology
  • Polymorphism, Restriction Fragment Length
  • Pre-Eclampsia / blood
  • Pre-Eclampsia / diagnosis*
  • Pregnancy
  • Receptors, Complement 3b / biosynthesis*
  • Receptors, Complement 3b / deficiency
  • Receptors, Complement 3b / genetics


  • Receptors, Complement 3b
  • Peptide Hydrolases