Figure 5. Restoration of MMP-9 Activity in MMP-9-Deficient/HPV16 Mice by Bone Marrow Transplantation.
(A) Scheme of bone marrow transplantation (BMT) protocol where 1-month-old mice (HPV16/MMP-9 +/–, HPV16/MMP-9 –/–) were lethally irradiated (7.5 Gy) and transplanted with BM-d cells (1 × 106) from nontransgenic donor mice (MMP-9 +/+ or MMP-9 –/–). Each cohort contained a minimum of ten animals. Ear biopsies were taken at 8 and 16 weeks post-BMT when animals were 3 and 5 months of age. All animals were studied either until tumors appeared, or animals developed health-compromising phenotypes, or until 12 months of age. (B) Gelatin-substrate zymography of BM-d cells (1 × 106) from MMP-9 +/+ (+/+, lane 1) and MMP-9 –/– (–/–, lane 2) donor mice. An arrow indicates enzymatic activity corresponding to proMMP-9.
(C) Gelatin-substrate zymography of tissue biopsies from HPV16/MMP-9 –/– mice reconstituted with either wild-type (+/+) or MMP-9-deficient (–/–) BM-d cells (1 × 106) at 8 and 16 weeks post-BMT. Presence of enzymatic activity corresponding to pro- and active MMP-9, pro- and active MMP-2, as well as an uncharacterized gelatinase are indicated. Molecular weight markers (kDa) are shown at right.