Modulation of bovine platelet function by C-reactive protein

The addition of C-reactive protein (CRP) to bovine platelets suspended in homologous plasma consistently produced a reversible aggregation response following stimulation with either platelet activating factor or adenosine diphosphate while untreated control samples exhibited irreversible aggregation. This deaggregation response was independent of the amount of CRP incorporated into the platelet aggregates but did appear to be mediated through a component either present in bovine plasma or loosely bound to the exterior platelet membrane. The aggregation response of bovine platelets, separated from plasma by gel-filtration, was not affected by the addition of CRP to the platelet suspensions. It is proposed that one of the physiological actions of bovine CRP is to modulate platelet function.