Mechanisms of Treatment Effects Using Cultured, Allogeneic Mesenchymal Stromal Stem Cells (MSCs) in Knee Osteoarthritis

Luminex assay is a type of immunoassay that precisely measures multiple analytes in one sample. It is a bead-based immunoassay that allows for multiplex detection of analytes simultaneously. Color-coded microspheres or beads are internally dyed with different proportions of red and infrared fluorophores that correspond to a distinct spectral signature or bead region. The quantification of multiple cytokines and other biomarkers in samples provides critical information about biological processes and diseases.

Enzyme-linked immunosorbent assay (ELISA) is the main approach for the sensitive quantification of protein biomarkers in body fluids and is currently employed in clinical laboratories for the measurement of clinical markers. It also constitutes the main methodological approach for biomarker validation and further qualification.

Quantitative real-time PCR (qRT-PCR) is a major development of PCR technology that enables reliable detection and measurement of products generated during each cycle of PCR process. The detection of changes in fluorescence intensity during the reaction enables to follow the PCR reaction in real time. qRT-PCR is comprised of several steps: 1. RNA is isolated from target tissue/cells, 2. mRNA is reverse-transcribed to cDNA, 3. modified gene-specific PCR primers are used to amplify a segment of the cDNA of interest, following the reaction in real time, 4. the initial concentration of the selected transcript in a specific tissue or cell type is calculated from the exponential phase of the reaction.

Knee injury and Osteoarthritis Outcome Score (KOOS) assesses patient pain (9 items), other symptoms (7 items), function in daily living (17 items), function in sport and recreation (5 items), and knee related quality of life (4 items). Scores range from 0 to 100 with a score of 0 indicating the worst possible knee symptoms and 100 indicating no knee symptoms.

The Visual Analogue Scale (VAS) measures pain intensity. The VAS consists of a 10cm line, with two end points representing 0 ('no pain') and 10 ('the worst pain imaginable').

EQ-5D-3L descriptive system consists of 5 dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression . Each dimension has 3 levels: no problems, some problems, and extreme problems. The respondent is asked to indicate his or her health state by ticking the box that marks the most appropriate level of problems in each dimension. A unique health state can be described according to the responses to the 5 questions. Health states defined in this way may be converted into a single summary index by applying a formula that attaches values to each of the levels in each dimension. States can be converted to a single value where 1 is equivalent to full health and 0 to a state equivalent to death.

EQ-VAS records the patient's self-rated health on a vertical visual analogue scale from 0 to 100, where 0 represents the worst health state imaginable and 100 represents the best health state imaginable.

Serious adverse events (SAE) are defined as any complication requiring hospitalization.