The HLA Technologist and Director Certification Program for Histocompatibility Testing of the Japanese Society for Histocompatibility and Immunogenetics (JSHI) offers various programs and training opportunities for the members to be certified as the expert. Here we will make comment on difficult questions from past paper tests to help your study. In addition, medical ethics issues will be mentioned to provide a learning opportunity.

Hematopoietic stem cell transplantation (HSCT) from HLA-mismatched donor has come to be performed more frequently than before. The risks of graft failure and graft-versus-host disease (GVHD) are higher in HLA-mismatched HSCT than HLA-matched HSCT. HLA-specific antibody, HLA-specific T lymphocytes, and activated NK cells due to a lack of inhibitory signal, but not HLA molecule itself, cause graft failure and GVHD. This text starts with a quick review of the requirement for HSCT donor, followed by the review of the effect of HLA-specific antibody, HLA-specific T lymphocytes, and activated NK cells on graft failure, acute GVHD, and chronic GVHD, The effect of minor histocompatibility antigen-specific antibody and T lymphocytes on graft failure and GVHD will be also discussed.

The most common type of transplantation is a blood transfusion. The American Society for Histocompatibility and Immunogenetics (ASHI) accredited laboratories are required to perform blood tests for transplant and blood transfusion such as DNA typing, flow cytometry technology, HLA typing, and ABO/RhD typing in accordance with the standards of ASHI. Recent medical technologists perform a wide range of new clinical laboratory tests and operate new laboratory equipment in immunological and DNA analysis for transplant and blood transfusion. Therefore, advanced training is required to become a medical technologist, and the curriculum of the school to become a medical technologist was revised this year. This short review presents an overview of the current basic blood tests for transplant and blood transfusion under the new curriculum classification.