FCGR2A and congenital rubella syndrome: Whileincorporating an Fc moiety into these construct can be crucial forhalf-life extension,47−49 the presence of an Fc with immune-effector functionis not beneficial in the context of a TCE strategy, and is in factdetrimental due to the undesired depletion of engaged T cells anddue to cytokine release syndrome (CRS) arising from immune overactivationthrough FcγR engagement.50 As inthis case the goal was to generate a proof-of-concept bispecific SynAbrather than a therapeutically relevant moiety, we used FcCD205 even though as a native Fc it has effector functionwhich is suboptimal for a TCE.