Open AccessInduction of Effector and Memory Cellular Immunity in a Patient with Long-Term Complete Molecular Response to Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia
Author(s) -
Jo Tatsuro,
Shioya Haruna,
Tominaga Hiroo,
Sakai Takahiro,
Hayashi Shizuka,
Matsuzaka Kaori,
Kaneko Yohei,
Matsuo Masatoshi,
Taguchi Jun
Publication year - 2020
Publication title -
case reports in oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.365
H-Index - 19
ISSN - 1662-6575
DOI - 10.1159/000508997
Subject(s) - case report
This case report is about a patient who suffered from Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukemia. The blasts were positive for myeloid-lineage markers including CD13 and CD33, as well as B-cell-lineage markers. Minor bcr-abl1 mRNA was detected by real-time quantitative polymerase chain reaction. Chromosomal abnormality monosomy 7 was also observed, in addition to Ph1. Despite treatment difficulties that were anticipated based on these findings, the patient had long-time complete molecular response (CMR) for approximately 5 years using chemotherapy and two tyrosine kinase inhibitors, imatinib and dasatinib. Lymphocytes were elevated after the patient switched from imatinib to dasatinib, and a T-cell receptor (TCR) V beta gene repertoire analysis revealed oligoclonal expansion of effector and memory cytotoxic T lymphocytes (CTLs), including Wilms tumor 1-specific CTLs. More specifically, the two memory CTLs expressing TCR V beta 3 and V beta 7.1 gradually increased after dasatinib administration. The activation and maintenance of anti-leukemia immunity may have allowed the patient to obtain long-time CMR. These results highlight that obtaining memory CTLs for leukemia cells may lead to safe withdrawal from dasatinib in the patient.