RESUMO
Introduction: The new coronavirus disease, COVID-19, poses complex challenges exacerbated by several factors, with respiratory tissue lesions being notably significant among them. Consequently, there is a pressing need to identify informative biological markers that can indicate the severity of the disease. Several studies have highlighted the involvement of proteins such as APOA1, XPNPEP2, ORP150, CUBN, HCII, and CREB3L3 in these respiratory tissue lesions. However, there is a lack of information regarding antibodies to these proteins in the human body, which could potentially serve as valuable diagnostic markers for COVID-19. Simultaneously, it is relevant to select biological fluids that can be obtained without invasive procedures. Urine is one such fluid, but its effect on clinical laboratory analysis is not yet fully understood due to lack of study on its composition. Methods: Methods used in this study are as follows: total serum protein analysis; ELISA on moderate and severe COVID-19 patients' serum and urine; bioinformatic methods: ROC analysis, PCA, SVM. Results and discussion: The levels of antiAPOA1, antiXPNPEP2, antiORP150, antiCUBN, antiHCII, and antiCREB3L3 exhibit gradual fluctuations ranging from moderate to severe in both the serum and urine of COVID-19 patients. However, the diagnostic value of individual anti-protein antibodies is low, in both blood serum and urine. On the contrary, joint detection of these antibodies in patients' serum significantly increases the diagnostic value as demonstrated by the results of principal component analysis (PCA) and support vector machine (SVM). The non-linear regression model achieved an accuracy of 0.833. Furthermore, PCA aided in identifying serum protein markers that have the greatest impact on patient group discrimination. The study revealed that serum serves as a superior analyte for describing protein quantification due to its consistent composition and lack of organic salts and drug residues, which can otherwise affect protein stability.
RESUMO
Human platelet lysate (HPL) is a promising alternative to fetal calf serum (FCS) for the expansion of adipose tissue mesenchymal stromal cells (AT-MSCs) for translational medicine applications. However, some biological effects of HPL are still to be elucidated. We aimed to compare complex characteristics, such as cell morphology, proliferative activity, differentiation potential, and especially monolayer recovery, DNA integrity, and the gene expression pattern, between AT-MSCs cultured with HPL or FCS. Primary AT-MSC cultures were expanded in medium containing FCS or pooled HPL. Cell growth and proliferation were estimated by cell doubling time and the monolayer formation rate, while migration was assessed by wound-healing assay. The capacity for adipogenic and osteogenic differentiation was evaluated by alkaline phosphatase and Oil Red O staining. DNA integrity was evaluated by comet assay, and analysis of gene expression by real-time PCR. Media supplemented with HPL or FCS provided a similar surface immunophenotype, cell morphology (except some cell dimensions and a bigger colony size in HPL), DNA integrity, and rate of wound healing. Meanwhile, AT-MSC proliferated more intensively in HPL-supplemented media (especially at 5% HPL) and had a reduced doubling population time. AT-MSC in HPL had increased adipogenic potential and similar osteogenic potential in comparison with FCS. Our results indicate the feasibility and evident prospects for the use of pooled HPL as an alternative to FCS and safe non-xenogenic growth supplement for ex vivo expansion of clinical-grade AT-MSCs for regenerative medicine purposes.
