Gene-specific PCR typing of killer cell immunoglobulin-like receptors.

By interacting with specific HLA class I molecules, the killer cell immunoglobulin-like receptors (KIR) regulate the effector function of natural killer (NK) cells and subsets of CD8 T cells. The KIR receptors and HLA class I ligands are encoded by unlinked polymorphic gene families located on different human chromosomes, 19 and 6, respectively. The number and type of KIR genes are substantially variable between individuals, which may contribute to human diversity in responding to infection, malignancy and allogeneic transplants. PCR typing using sequence-specific primers (PCR-SSP) is the most commonly used method to determine KIR gene content. This chapter describes a step-by-step protocol for PCR-SSP typing to identify the presence and absence of all 16 known KIR genes. Moreover, the chapter provides the basic rules to verify the accuracy of KIR genotyping results and explains specific methods for the data analysis.