Recent studies in transgenic mice confirmed that C-reactive protein is protective against microbial pathogens. This is consistent with its ability in vitro to bind microbes, activate the complement classical pathway, and engage FcγRI and FcγRII. However, in transgenic mice protection also requires the alternative pathway of complement, and FcγRI is dispensable. © 2002 Éditions scientifiques et médicales Elsevier SAS. All rights reserved.