Genetic background of anti‐ CD99 producers in Japan and analysis of hemolytic transfusion reactions due to anti‐ CD99
Year: 2025
Type: article
Study design: Case Report
Abstract: BACKGROUND: and CD99. CD99 is known to be carried on both the X and Y chromosomes in pseudoautosomal region 1. We identified five unrelated Japanese individuals with anti-CD99 and investigated their genomic background as well as the clinical significance of anti-CD99. STUDY DESIGN AND METHODS: Analysis of CD99 expression on RBCs and a modified monocyte monolayer assay was performed using flow cytometry. Genomic DNA was obtained from the five anti-CD99 producers to identify the deleted region responsible for the lack of CD99, and we conducted a long polymerase chain reaction using primer pairs specific for CD99 and GYG2. RESULTS: CD99 expression from the Y chromosome was higher than that from the X chromosome. The five anti-CD99 plasma samples gave varied agglutination strengths with the red blood cells (RBCs) expressing high and low CD99 levels, in the antiglobulin test. The phagocytosis rate of anti-CD99-sensitized RBCs was 76.6% in one case indicating a risk of hemolytic transfusion reactions (HTR), and it correlated with the level of CD99 expression. The deleted region spanned 115 kb, from CD99 exon 3 to GYG2 exon 1. All five anti-CD99 producers were homozygous for the large deletion allele. DISCUSSION: All five anti-CD99 producers were females with a history of pregnancy in Kyushu, Japan, and this deletion allele may thus be endemic. Our results indicated the possibility of HTR due to anti-CD99, and the risk is low when transfusing RBC products from Xg(a-) females with a low expression of CD99.
Source: Transfusion
DOI: 10.1111/trf.18126
Authors: Naoko Watanabe‐Okochi, Hatsue Tsuneyama, Makoto Kumamoto, Sho Tanaka, Tomoko Nakazono, Kuninori Ichinomiya, Yumi Suzuki, Kenichi Ogasawara, Makoto Uchikawa, Shinichi Naganuma, Sumie Hayashi, Hiroyuki Igarashi, Nelson‐Hirokazu Tsuno, Kazuo Muroi
Institution: Japanese Red Cross Society, Japan
Language: English
Topic: Blood groups and transfusion
Subfield: Hematology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4407349050