The binding of MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) with Ocrelizumab and Rituximab was tested using ELISA.
The coating antigen used was Ocrelizumab or Rituximab at a concentration of 1 µg/mL. The MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) was used at dilutions starting from 0.5 µg/mL. The results demonstrate that the antibody specifically recognizes Ocrelizumab but does not recognize Rituximab

BLI (Biolayer interferometry) binding affinity measurements of MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) to Ocrelizumab.
Ocrelizumab captured on HFC (Anti-Human IgG Fc) Probes can bind MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit with a dissociation constant (KD) of less than 1 pM.

MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) inhibits the binding of Ocrelizumab to Human CD20.
Coating antigen: Ocrelizumab, 1 µg/ml.
Human CD20 final concentration: 0.5 µg/ml.
Anti-Ocrelizumab antibody dilutions start from 10 μg/ml. MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) demonstrated significant inhibitory properties with an IC₅₀ value of 0.20 µg/ml.

Standard curve of Ocrelizumab sandwich ELISA by A02258 (12G10) and A02259 (15E7).
In this ELISA assay, MonoRab™ Anti-Ocrelizumab Antibody (12G10), mAb, Rabbit (GenScript, A02258) was coated at a concentration of 1 μg/ml, and MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) conjugated with Biotin was used as a detection antibody at a concentration of 0.5 μg/ml.
In this ELISA assay, a four-parameter logistic curve fitting program was used to create a standard curve with the R-Square equal to 0.99978. The typicaldynamic range of the assay is 5-320 ng/mL and its sensitivity of detecting Ocrelizumab is up to 5 ng/ml.

MRD analysis of the detection of Ocrelizumab in biological matrix.

The MRD is the minimum dilution necessary for the detection of Ocrelizumab in biological matrix with least interference. Serum samples from cynomolgus monkey were serially diluted to determine the MRD of this assay, and the test result suggestedthat MRD was as 1:10.
In this ELISA assay, MonoRab™ Anti-Ocrelizumab Antibody (12G10), mAb, Rabbit (GenScript, A02258) was coated at a concentration of 1 μg/ml, and MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) conjugated with Biotin was used as a detection antibody at a concentration of 0.5 μg/ml.

Specificity analysis of the detection of Ocrelizumab.

Ocrelizumab standard samples at 8 concentrations were spiked with 10 µg/mL of human IgG1. The test result demonstrated that the high concentration of human IgG1 did not interfere with the detection of Ocrelizumab.
In this ELISA assay, MonoRab™ Anti-Ocrelizumab Antibody (12G10), mAb, Rabbit (GenScript, A02258) was coated at a concentration of 1 μg/ml, and MonoRab™ Anti-Ocrelizumab Antibody (15E7), mAb, Rabbit (GenScript, A02259) conjugated with Biotin was used as a detection antibody at a concentration of 0.5 μg/ml.