Clot retraction in a factor XIII free system

The role of Factor XIII in clot retraction was studied using the plasma from Factor XIII-deficient patients. Time course experiments revealed no significant difference in clot retraction between a plasma deficient in Factor XIII and one to which purified Factor XIII had been added. Using Factor XIII-free fibrinogen and Factor XIII-deficient platelets, it is shown that there is no significant difference in clot retraction with or without added Factor XIII.