title: Anti-D (WinRho SD) treatment of children with chronic autoimmune thrombocytopenic purpura stimulates transient cytokine/chemokine production.
abstract: Intravenous anti-D is often used in the treatment of autoimmune thrombocytopenic purpura (AITP), but little is known about its mechanisms of action. To investigate anti-D's potential in vivo mechanism(s) of action, a small group (N = 7) of children with chronic AITP was studied. The children initially received either 25 or 50 microg/kg of WinRho-SD in a four-cycle cross-over trial, and peripheral blood samples from the first and third cycles were assessed for cytokine levels at pre-treatment, 3 hr, 1 day, and 8 days post-treatment. Results showed that platelet counts significantly increased in all the children by day 8 post-treatment. Analysis of serum by ELISA showed that there was a significant but transient rise in both pro- and anti-inflammatory cytokine/chemokine levels (e.g., IL1RA, IL6, GM-CSF, MCP-1 alpha, TNF-alpha and MCP-1) by 3 hr post-treatment in both cycles which returned to baseline levels by 8 days post-treatment. These results suggest that anti-D administration may initially activate the RES in the form of cytokine/chemokine secretion, which is subsequently followed by an increase in platelet counts. It is possible that the induced cytokine/chemokine storm may have an effect on several physiological processes such as those mediating either adverse effects or potentially RES phagocytic activity.
authors.affiliation: Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, Toronoto, Ontario, Canada. semplej@smh.toronto.on.ca
authors.forename: J W
authors.initials: JW
authors.lastname: Semple
authors.forename: D
authors.initials: D
authors.lastname: Allen
authors.forename: M
authors.initials: M
authors.lastname: Rutherford
authors.forename: M
authors.initials: M
authors.lastname: Woloski
authors.forename: M
authors.initials: M
authors.lastname: David
authors.forename: C
authors.initials: C
authors.lastname: Wakefield
authors.forename: S
authors.initials: S
authors.lastname: Butchart
authors.forename: J
authors.initials: J
authors.lastname: Freedman
authors.forename: V
authors.initials: V
authors.lastname: Blanchette
mesh_terms: D018925:Chemokines / Q000096:biosynthesis* / Q000097:blood; D002648:Child; D002908:Chronic Disease; D018592:Cross-Over Studies; D016207:Cytokines / Q000096:biosynthesis* / Q000097:blood / Q000187:drug effects; D006801:Humans; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000188:drug therapy*; D018029:Rho(D) Immune Globulin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D018925:Chemokines; D016207:Cytokines; D018029:Rho(D) Immune Globulin