Equal contribution of platelets and vascular Gas6 to thrombus generation. (A) Platelet counts were equivalent in whole blood drawn from WT and Gas6^−/− mice. (B) Platelet depletion was achieved by injection of rabbit anti–mouse thrombocyte serum. Platelet counts were successfully reduced by injection of rabbit anti–mouse thrombocyte serum and successfully restored after injection of platelets from a donor mouse to thrombocytopenic mice (n = 4). *P < .05, WT depleted versus WT reconstituted. #P < .05, Gas6^−/− depleted versus Gas6^−/− reconstituted. (C) Thrombosis was induced in the 4 groups of mice generated by the platelet depletion/reconstitution as indicated in the figure. WT or Gas6^−/− mice receiving Gas6^−/− or WT platelets, respectively, had thrombi of intermediate weight, similar to the results the bone marrow transplantation experiments (n = 4 or 5). #P < .001.