Intended Use 

The  Antibody to infliximab (Remicade®) Enzyme-Linked-ImmunoSorbentAssay (ELISA) Kit is intended for the qualitative determination of antibodies to infliximab (Remicade®) in serum and plasma. It is for professional use only. 

Summary and Explanation 

Infliximab (Remicade®) is a chimeric monoclonal antibody and used to treat autoimmune disorders. Infliximab reduces the amount of active human tumour necrosis factor  alpha (hTNFa) in the body by binding to it and preventing it frm signaling the receptors for TNFa on the surface of various cell types. TNFa is one of the key cytokines that triggers and sustains the inflammatory reactions. Infliximab (Remicade) is used for the treatment of psoriasis, Crohn's disease, ankylosing spondylitis, psoriatic arthritis, rheumatoid arthritis, ulcerative colitis, and approved by FDA. 

 One of the major concern, despite of its wide usage, is potential development of anti-infliximab antibodies (ATI) which in turn may interfere with infliximab (Remicade®) efficacy as mainly judged by observing the relapse of signs and symptoms of disease and necessitate dose-escalation or potentially ending up the treatment. In this context, demonstration of anti-infliximab antibodies during treatment with infliximab (Remicade®) has a major concern and monitoring for the presence and/or quantitation of specific antibodies during clinical trials is an important issue for follow up of the treatment regimens. The Matriks Biotek ATI ELISA Kit can be efficiently used for monitoring infliximab-specific antibodies during therapy and offers the clinician a tool for decision on possible preventive measures such as possible addition of immunosuppressive drug to reduce anti-infliximab antibodies. With this Matriks Biotek ELISA test, antibodies to infliximab can be detected in patients receiving Remicade®. Test Principle The Matriks Biotek Antibody to infliximab (Remicade®) ELISA is a sandwich assay for the determination of antibodies against infliximab in serum and plasma samples. During the first incubation period, antibodies to infliximab (ATI) in patient serum/ plasma samples are captured by the drug infliximab (Remicade®) coated on the wall of the microtiter wells. After washing away the unbound components from samples, a peroxidase-labelled specific conjugate is added to each well and then incubated. After a second washing step, the bound enzymatic activity is detected by addition of tetramethylbenzidine (TMB) chromogen-substrate. Finally, the reaction is terminated with an acidic stop solution. The intensity of the reaction color is directly proportional to the concentration of ATI in sample. 

Storage and Stability 

The kit is shipped at ambient temperature and should be stored at 2-8°C. Keep away from heat or direct sun light. The storage and stability of specimen and prepared reagents is stated in the corresponding chapters. The strips of microtiter plate is stable up to the expiry date of the kit in the broken, but tightly closed bag when stored at 2– 8°C.

 Specimen Collection and Storage 

Serum, Plasma (EDTA, Heparin)* 

The usual precautions for venipuncture should be observed. It is important to preserve the chemical integrity of a blood specimen from the moment it is collected until it is assayed. Do not use grossly hemolytic, icteric or grossly lipemic specimens. Samples appearing turbid should be centrifuged before testing to remove any particulate material. Storage: 2-8°C for 7 days or -20°C for 6 months. Keep away from heat or direct sun light Avoid repeated freeze-thaw cycles. 

Infliximab (Remicade®) infusion camouflages/masks the presence of antibody to infliximab (ATI) in serum/plasma samples. Therefore, blood sampling time is critical for detection of ATI. Matriks Biotek Laboratories propose to obtain blood sample just before the infusion of infliximab (Remicade®) or at least 2 weeks after the infusion of infliximab (Remicade®).