Monocyte-platelet interaction in immune and nonimmune thrombocytopenia

Authors

Mansoor Saleh, Aga Khan UniversityFollow
D L. Moore, University of Alabama at Birmingham, USA
J Y. Lee, University of Alabama at Birmingham, USA
A F. LoBuglio, University of Alabama at Birmingham, USA

Document Type

Article

Department

Haematology and Oncology, East Africa

Abstract

Platelets from 24 patients with immune thrombocytopenia resistant to standard therapy (refractory ITP), 35 patients with nonimmune thrombocytopenia (non-ITP), and 32 normal donors were studied in regard to platelet surface-bound IgG (PBIgG) and the ability of these platelets to be bound by human monocytes in vitro (monocyte-platelet rosette assay). Fourteen (58%) of the platelet samples from refractory ITP patients but none (0%) from the non-ITP or control donors had PBIgG greater than 800 molecules IgG/platelet. Seventeen of 24 (71%) of the ITP patients had platelets which demonstrated increased monocyte- platelet rosette formation [rosette index (RI) greater than 2], whereas only four (11%) of the non-ITP patients had such platelets. There was a direct correlation between PBIgG and rosette index for the platelets from resistant ITP patients. There was no correlation of severity of thrombocytopenia with PBIgG or rosette index. Monocyte-platelet interaction in the presence of elevated PBIgG is mediated through the monocyte Fc-receptor. Platelets from five of ten refractory ITP patients with PBIgG less than 800 molecules IgG/platelet had increased rosette formation. Monocyte-platelet interaction in the absence of increased PBIgG may be due to small amounts of platelet surface IgG which are still able to mediate monocyte Fc-receptor interaction or to alternate membrane receptor interaction through the monocyte C3 receptor. Our data underscore the pathophysiologic relevance of monocyte/macrophage-mediated interaction in immune platelet destruction syndromes.

Comments

This work was published before the author joined Aga Khan University.

Publication (Name of Journal)

Blood

DOI

https://doi.org/10.1182/blood.V74.4.1328.1328

Recommended Citation

Saleh, M., Moore, D. L., Lee, J. Y., LoBuglio, A. F. (1989). Monocyte-platelet interaction in immune and nonimmune thrombocytopenia. Blood, 74(4), 1328-1331.
Available at: https://ecommons.aku.edu/eastafrica_fhs_mc_haematol_oncol/151