Biologic responses of M1-V1 and M1-G1 to IL-6.

(A) Changes in total viable cell number during the culture with or without recombinant human (rh) interleukin 6 (IL-6). M1-V1 and M1-G1 cells were seeded at a cell density 100/μL and cultured with or without 20 ng/mL rhIL-6. Total viable cell number was counted by trypan blue dye exclusion method. M1-V1, open circle, IL-6 (-), closed circle, IL-6 (+); M1-G1, open square, IL-6 (-), closed square, IL-6 (+). The results are shown as the mean ± SD of triplicate cultures. (B) Light micrograph of M1-V1, M1-G1, and M1-G2 before and after 72-hour culture with rhIL-6. Cytocentrifugation preparation from each culture was stained with May-Gr ¸nwald-Giemsa (magnification × 100). (C) Flow cytometric analyses on expression of F4/80 and CD32 before and after 72-hour culture with rhIL-6. Expression of F4/80 and CD32 in the cultured cells was examined by staining with anti-F4/80 or anti-CD32 monoclonal antibody (—) with a reference to control antibody of the same isotype (---).