Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (996 page)

   
Repeat HLA typing of recipient
using a new sample such that the individual’s HLA typing is confirmed prior to final donor selection for related or unrelated transplantation.

   
Repeat HLA typing of a related or unrelated stem cell donor
using a new sample such that the donor’s HLA typing is confirmed prior to stem cell collection. For unrelated donors, registry data are acceptable as the first of these two samples.

   
Identity typing
can be performed by intermediate-resolution HLA-A, HLA-B and HLA-DRB1 typing by PCR-SSOP.

   
Transplant program coordinators
are responsible for requesting the second sample for identity typing before final donor selection is made. For donors, the registry typing will be considered as the first typing and the extended high-resolution typing will be considered as the second typing.

   To ensure maximum accuracy:

   Two sample collections on different dates, the second date should be prior to the final donor selection for related or unrelated donors or cords.

   Two sample types (blood and buccal swab) if the first sample is blood. Buccal swabs are acceptable as the first or second or both collections. Buccal swab is recommended for patients with any acute diagnosis, for example, AML and ALL with blasts.

   Two testing methods, PCR-SSOP/SSP or SBT

   KIR typing

   HSCT for leukemia can play a major role in reducing the risk of relapse by inducing a graft versus leukemia (GVL) effect. The effectiveness of mismatching inhibitory killer cell immunoglobulin–like receptors (KIR) on donor natural killer (NK) cells as a mechanism for GVL is being studied extensively. Together, the gene content of KIR, the T-cell and NK cell components of the graft, the graft source, the conditioning regimen, and mechanisms to reduce graft versus host disease (GVHD), will improve the overall benefit of HSCT.

   Generic KIR typing, to detect the presence/absence of the inhibitory KIR genes, can be performed on selected patients and donors. The ligand matching information and the B-haplotype content can provide assistance in selecting the best possible donors/cords. The matching and mismatching of inhibitory KIR in the graft verse host direction can be determined based on the patient HLA ligand and donor inhibitory KIR.

   Null allele typing