Anaplasma phagocytophilum infection induces protracted neutrophil degranulation

Anaplasma phagocytophilum-infected neutrophil degranulation could exacerbate inflammation. Thus, the degranulation of infected neutrophils was assayed. Infected neutrophils expressed CD11b and CD66b, and supernatants of infected neutrophils showed more proMMP-9 and MMP-9 activity than controls and continued to do so for greater than or equal to18 h. Degranulation-related inflammatory tissue injury may account for some clinical manifestations in human granulocytic anaplasmosis.