RT-PCR and reverse zymographic analyses of RNA extracted from Raji and Jurkat cells and media conditioned by Raji and Jurkat cell lines stimulated with IL-6. (A) RNA extracted from Raji and Jurkat cell lines was analyzed for the expression of MMP-9, MMP-2, and TIMP-1 by RT-PCR as described in the Materials and Methods. Cells were cultured in serum-free media with and without IL-6 (100 ng/mL). Each analysis was internally controlled by inclusion of GAPDH primers. (B) Reverse zymogram of conditioned media from Raji and Jurkat cell lines stimulated 100 ng/mL IL-6. Conditioned medium (CM) from BHK cells was used as a positive control for TIMP activities.