Heat inactivation can differentiate between IgG and IgM antibodies in the pretransplant cross match.
The presence of IgG antibodies in the pretransplant cross-match (XM) test results in hyperacute rejection, but IgM antibodies are inconsequential. The XM should be able to differentiate between IgG and IgM antibodies. This study evaluated 3 methods. This study was based on 500 patients for whom XM were performed between 2004 and 2006 with all 3 techniques. Two patient sera were used: normal serum and heat inactivated serum, which was prepared by incubating patient serum at 63 degrees C for 10 minutes to destroy IgM antibodies. The efficiencies of flow cytometry XM (FC-XM), dithiothreitol complement-dependent microlymphocytotoxicity (DTT/CDC-XM), and heat inactivation (HI-CDC-XM) to differentiate between IgG and IgM were evaluated by using both sera. Patients with positive XM, and negative HI-CDC-XM were reported as negative XM. During the study period, there were 70 patients with positive B-cell XM. Forty-nine became negative after HI-XM, and 21 remained positive. Only 34 cases became negative after DTT-CDC-XM and 36 remained positive. HI-CDC-XM was comparable to FC-XM; all patients testing negative with this technique experienced successful renal transplantations without hyperacute, accelerated, or acute rejection episodes. Our study showed that HI-CDC-XM was effective at exclude donor-specific IgM antibodies, a result which was comparable to FCXM to detect only IgG antibodies. HI is simple and rapid and does not involve any extra equipment or cost.
Al-Muzairai
I A
IA
Immunology and Organ Transplantation Departments, Hamad Al-Essa Organ Transplantation Center, Kuwait. rana@kma.org.kw
Mansour
M
M
Almajed
L
L
Alkanderi
N
N
Alshatti
N
N
Samhan
M
M
D001788:Blood Grouping and Crossmatching / Q000379:methods; D006084:Graft Rejection / Q000517:prevention & control; D006650:Histocompatibility Testing / Q000379:methods; D006358:Hot Temperature; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D007075:Immunoglobulin M / Q000097:blood / Q000276:immunology*; D007518:Isoantibodies / Q000097:blood*; D016030:Kidney Transplantation / Q000276:immunology*; D011300:Preoperative Care
D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007518:Isoantibodies