ALEUTIAN MINK DISEASE PARVOVIRUS INFECTION OF K562 CELLS IS ANTIBODY-DEPENDENT AND IS MEDIATED VIA AN FC(GAMMA)RII RECEPTOR - BRIEF REPORT

Aleutian mink disease parvovirus (ADV) infects macrophages but infecti on is restricted. Using the human macrophage cell line U337, we report ed infection to be antibody-dependent [22, 23]. Recently, we learned t hat the U937 cells were contaminated with the human cell line, K562 [1 2]. To clarify which cell line actually supported ADV infection, we st udied the antibody-dependent enhancement (ADE) of ADV infection in pur e lines of U937 and K562. After infection with ADV complexed with mink anti-ADV antibody, up to 10% of the K562 cells, but none of the U937 cells showed evidence of infection. These results indicated that K562 cells, but not U937 cells, were susceptible to ADV. ADV-infected cultu res of K562 were: sorted by flow cytometry after staining with a murin e monoclonal antibody (IV.3) directed against Fc(gamma)RII. Only cells that were IV.3 positive supported ADV gene expression. Also, preincub ation of K562 cells with IV.3 blocked ADV infection by more than 90%. These results established that the ADE of ADV in K562 is Fc(gamma)RIIA -mediated.