An analysis of matrix metalloproteinases (MMPs) activity in excretory/secretory antigens of Oestrus ovis larvae from sheep

Abstract

The present study was carried out to ascertain the presence of matrix metalloproteinases activity in excretory/secretory (E/S) antigens of larvae of Oestrus ovis by gelatin zymography. The larvae of O. ovis were collected from sheep slaughtered at local abattoirs in Orathanadu and Thanjavur. Live, intact larvae were washed thoroughly with phosphate buffered saline (PBS, pH 7.4) and suspended in PBS at 37°C in an incubator for 16 h. After incubation, the fluid was collected, centrifuged at 10,000 rpm for 15 min at 4°C and the supernatant was used as E/S antigen. On gelatin zymographic analysis, presence of 220 kDa MMP-9 (pro form) and 210 kDa (active form) homodimeric forms was observed as a fainter band at the top of the gelatin zymogram. A clear, bright gelatinolytic activity was observed at 20 kDa level at the bottom of the zymogram. The other forms of MMP-9, viz. 135 heterodimeric form was observed at 125 kDa size (active form) as a fainter band and the 72 kDa MMP-2 was detected as a fainter bands at 72 kDa (pro form) and 62 kDa (active form). The strong gelatinolytic activity detected at 20 kDa level of E/S antigens of O. ovis was the catalytic breakdown products of the MMPs found in the fluid. It was concluded that the activity of the MMPs in the E/S antigens of O. ovis was very strong, helping in the migration of the larvae from one site to the other.