title: Eryptotic phenotype in chronic myeloid leukemia: contribution of neutrophilic cathepsin g.
abstract: In pathological conditions with concurrent neutrophilia, modifications of erythrocyte membrane proteins are reported. In chronic myeloid leukemia (CML), a myeloproliferative disease wherein neutrophilia is accompanied by enhanced erythrophagocytosis, we report for the first time excessive cleavage of erythrocyte band 3. Distinct fragments of band 3 serve as senescent cell antigens leading to erythrophagocytosis. Using immunoproteomics, we report the identification of immunogenic 43 kDa fragment of band 3 in 68% of CML samples compared to their detection in only 38% of healthy individuals. Thus, excessive fragmentation of band 3 in CML, detected in our study, corroborated with the eryptotic phenotype. We demonstrate the role of neutrophilic cathepsin G, detected as an immunogen on erythrocyte membrane, in band 3 cleavage. Cathepsin G from serum adsorbs to the erythrocyte membrane to mediate cleavage of band 3 and therefore contribute to the eryptotic phenotype in CML.
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi Mumbai 410 210, India.
authors.forename: Rukmini
authors.initials: R
authors.lastname: Govekar
authors.forename: Poonam
authors.initials: P
authors.lastname: Kawle
authors.forename: Renjan
authors.initials: R
authors.lastname: Thomas
authors.forename: Suresh
authors.initials: S
authors.lastname: Advani
authors.forename: Sheena
authors.initials: S
authors.lastname: Pv
authors.forename: Surekha
authors.initials: S
authors.lastname: Zingde