IF 1 ▁is ▁a ▁protein ▁that ▁exists ▁in ▁the ▁cy top las m , ▁and ▁it ▁is ▁highly ▁evolution arily ▁conser ved . ▁It ▁is ▁also ▁possibly ▁identical ▁to ▁three ▁other ▁prote ins , ▁I ba - 2 , ▁MR F - 1 ▁( m icro gl ia ▁response ▁factor ) ▁and ▁d aint ain . ▁However ▁complete ▁functional ▁profiles ▁of ▁all ▁three ▁prote ins ▁and ▁how ▁they ▁overlap ▁is ▁unknown . ▁I BA 1 ▁is ▁a ▁ 1 7 - k Da ▁EF ▁hand ▁protein ▁that ▁is ▁specifically ▁expressed ▁in ▁macro ph ages ▁/ ▁micro gl ia ▁and ▁is ▁up reg ulated ▁during ▁the ▁activation ▁of ▁these ▁cells . ▁I ba 1 ▁expression ▁is ▁up - reg ulated ▁in ▁micro gl ia ▁following ▁n erve ▁injury , ▁central ▁nerv ous ▁system ▁is chem ia , ▁and ▁several ▁other ▁brain ▁dise ases . ▁ ▁A IF 1 ▁was ▁originally ▁discovered ▁in ▁a ther os cler otic ▁les ions ▁in ▁a ▁rat ▁model ▁of ▁chron ic ▁al log raft ▁card iac ▁re jection . ▁It ▁was ▁found ▁to ▁be ▁up reg ulated ▁in ▁macro ph ages ▁and ▁neut roph ils ▁in ▁response ▁to ▁the ▁cy tok ine ▁IF N - γ . ▁A IF 1 ▁expression ▁has ▁been ▁seen ▁to ▁increase ▁in ▁v asc ular ▁t issue ▁in ▁response ▁to ▁ar ter ial ▁injury , ▁specifically ▁it ▁is ▁found ▁in ▁activ ated ▁v asc ular ▁smooth ▁mus cle ▁cells ▁in ▁response ▁to ▁IF N - γ , ▁IL - 1 β , ▁and ▁T