When cross-bred with apolipoprotein E gene-deficient (apoe −/−) mice, which is a murine phenotype closely recapitulating the development of human atherosclerosis, mouse strains which result from these combinations (PTX3+/+ or PTX3+/− ApoE−/− versus PTX3−/− ApoE−/−) yielded exciting insights into the involvement of PTX3 in atherogenesis. The gene discussed is PTX3; the disease is atherosclerosis.