Plasma Levels of MMPs and TIMP-1 in Patients with Osteoarthritis After Recovery from COVID-19.

BACKGROUND: Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPS) play a key role in the pathogenesis of osteoarthritis (OA). Recent research showed the involvement of some MMPs in COVID-19, but the results are limited and contradictory. OBJECTIVE: In this study, we investigated the levels of MMPs (MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10) and TIMP-1 in the plasma of patients with OA after recovery from COVID- 19. METHODS: The experiment involved patients aged 39 to 80 diagnosed with knee OA. All study participants were divided into three research groups: the control group included healthy individuals, the group OA included patients with enrolled cases of OA, and the third group of OA and COVID-19 included patients with OA who recovered from COVID-19 6-9 months ago. The levels of MMPs and TIMP-1 were measured in plasma by enzyme-linked immunosorbent assay. RESULTS: The study showed a change in the levels of MMPs in patients with OA who had COVID- 19 and those who did not have a history of SARS-CoV-2 infection. Particularly, patients with OA who were infected with coronavirus established an increase in MMP-2, MMP-3, MMP-8, and MMP-9, compared to healthy controls. Compared to normal subjects, a significant decrease in MMP-10 and TIMP-1 was established in both groups of patients with OA and convalescent COVID-19. CONCLUSION: Thus, the results suggest that COVID-19 can affect the proteolysis-antiproteolysis system even after a long postinfectious state and may cause complications of existing musculoskeletal pathologies.

Asymptomatic SARS-CoV-2 Infection Is Associated With Higher Levels of Serum IL-17C, Matrix Metalloproteinase 10 and Fibroblast Growth Factors Than Mild Symptomatic COVID-19.

Young adults infected with SARS-CoV-2 are frequently asymptomatic or develop only mild disease. Because capturing representative mild and asymptomatic cases require active surveillance, they are less characterized than moderate or severe cases of COVID-19. However, a better understanding of SARS-CoV-2 asymptomatic infections might shed light into the immune mechanisms associated with the control of symptoms and protection. To this aim, we have determined the temporal dynamics of the humoral immune response, as well as the serum inflammatory profile, of mild and asymptomatic SARS-CoV-2 infections in a cohort of 172 initially seronegative prospectively studied United States Marine recruits, 149 of whom were subsequently found to be SARS-CoV-2 infected. The participants had blood samples taken, symptoms surveyed and PCR tests for SARS-CoV-2 performed periodically for up to 105 days. We found similar dynamics in the profiles of viral load and in the generation of specific antibody responses in asymptomatic and mild symptomatic participants. A proteomic analysis using an inflammatory panel including 92 analytes revealed a pattern of three temporal waves of inflammatory and immunoregulatory mediators, and a return to baseline for most of the inflammatory markers by 35 days post-infection. We found that 23 analytes were significantly higher in those participants that reported symptoms at the time of the first positive SARS-CoV-2 PCR compared with asymptomatic participants, including mostly chemokines and cytokines associated with inflammatory response or immune activation (i.e., TNF-α, TNF-ß, CXCL10, IL-8). Notably, we detected 7 analytes (IL-17C, MMP-10, FGF-19, FGF-21, FGF-23, CXCL5 and CCL23) that were higher in asymptomatic participants than in participants with symptoms; these are known to be involved in tissue repair and may be related to the control of symptoms. Overall, we found a serum proteomic signature that differentiates asymptomatic and mild symptomatic infections in young adults, including potential targets for developing new therapies and prognostic tests.