This non-therapeutic biosimilar antibody uses the same variable regions from the therapeutic antibody Rituximab making it ideal for research use. This Rituximab biosimilar reacts with human CD20. CD20 is a B cell-specific 33-37 kDa transmembrane protein which is also known as B-lymphocyte antigen, B1, and Bp35. CD20 plays roles in intracellular calcium regulation and B cell activation and is critical for an optimal B cell immune response against T-independent antigens. CD20 is first expressed after the induction of CD19 together with IgM during the pre-B to immature B cell transition in the bone marrow. It’s expression then increases during maturation with almost all mature B cells expressing some level of CD20. However, CD20 is not expressed by plasma blasts or plasma cells. CD20 is expressed by most B cell neoplasms, and is useful in diagnosing B cell lymphomas and leukemia’s. Many anti-CD20 monoclonal antibodies are currently being used to successfully treat leukemia’s, lymphomas, and various autoimmune diseases. Rituximab has depleting activity and mediates ADCC and CDC of CD20+ cells. This results in the elimination of B cells from the body.