Ocrelizumab Depletes CD20⁺ T Cells in Multiple Sclerosis Patients.

Ocrelizumab, a humanized monoclonal anti-CD20 antibody, has shown pronounced effects in reduction of disease activity in multiple sclerosis (MS) patients and has recently been approved for the treatment of patients with relapsing MS (RMS) and primary progressive MS (PPMS). CD20 is mainly expressed by B cells, but a subset of T cells (CD3⁺CD20⁺ T cells) also expresses CD20, and these CD20⁺ T cells are known to be a highly activated cell population. The blood of MS patients was analyzed with multicolor flow cytometry before and two weeks after treatment with ocrelizumab regarding the phenotype of peripheral blood mononuclear cells.

Detection and quantification of rituximab in the human urine.

B cell depletion by rituximab treatment might be inefficient in patients suffering from nephrotic syndrome. Due to the impaired glomerular filtration barrier a significant portion of the therapeutic antibody might be lost into the urinary space. In order to determine the amount of rituximab in the urine of such patients, CD20+ Daudi cells were stained with the patients' urine followed by a fluorochrome-labeled secondary antibody.