Profile of extracellular matrix metalloproteinase in healthy and infected Toggenburg goats with small ruminant lentivirus in Southeast Brazil

Small ruminant lentiviruses (SRLV) are difficult to diagnose due to their escape mechanisms. Therefore, proteomics is an alternative in the search for biomarkers through extracellular matrix metalloproteinases (MMPs), enzymes related to the immune response. In this sense, this study aimed to analyze the profile of MMPs in healthy and infected Toggenburg goats with chronic SRLV infection in Southeast Brazil. Five positive and five negative goats for SRLV were selected using the agar gel immunodiffusion (AGID) microtechnique, western blot (WB), and nested polymerase chain reaction (nPCR). All animals were submitted to blood collection by puncture of the jugular vein, followed by centrifugation to obtain blood plasma, protein quantification by the Bradford method, one-dimensional electrophoretic separation (1D), and identification of protease activity by zymography and confirmation via reverse zymography in the presence of MMP-2 through the action of tissue inhibitors (TIMP-2). The analysis of protein bands was performed using descriptive statistics and densitometry values for zymography were subjected to the Shapiro-Wilk test to determine normality. Little difference was observed in the occurrence of protein bands between groups. Regarding MMPs, no differences were observed in the expression of proMMP-9, MMP-9, and MMP-2 in animals affected by SRLV. TIMP-2 inhibited proMMP-2 and MMP-2 in all animals. Thus, the profile of protein bands does not change in healthy goats with chronic SRLV infection. The TIMP-2 expression allowed proving the existence of MMP-2 in animals chronically infected by SRLV via reverse zymography.