Transient deficiency of peripheral blood accessory cells in supporting T cell mitogenesis in patients suffering from chronic idiopathic thrombocytopenic purpura after intravenous gammaglobulin treatment

• Published in: Blut Vol. 51; no. 1; pp. 1 - 10
• Main Authors: Larocca, L M, Maggiano, N, Leone, G, Piantelli, M, Scribano, D, Musiani, P
• Format: Journal Article
• Language: English
• Published: Germany 01-07-1985
• Subjects: Antibodies, Monoclonal - immunology; Antigen-Presenting Cells - immunology; Blood Platelets - immunology; Blood Platelets - metabolism; Humans; Immunoglobulin G - therapeutic use; Injections, Intravenous; Lymphocyte Activation; Purpura, Thrombocytopenic - immunology; T-Lymphocytes - classification
• ISSN: 0006-5242; 1432-0584
• DOI: 10.1007/BF00320594

Mitogenic response of blood lymphocytes to phytohemagglutinin (PHA) and to OKT3 monoclonal antibodies was investigated in 7 patients suffering from chronic idiopathic thrombocytopenic purpura (ITP) before, during and after high-dose intravenous (i.v.) immunogammaglobulin (IgG) infusion. The platelet count rose above the pre-treatment values during infusion therapy in all patients but one. Five out of seven patients presented elevated platelet-associated IgG (PA-IgG) levels at the time of the first infusion; four of these showed an increase in platelet count and a transient reduction or normalization of PA-IgG after IgG infusion. Five out of seven patients showed an impairment of T lymphocyte mitogenic response to PHA and OKT3 before therapy. All patients responded to IgG therapy with a transient deficiency of FcR mediated monocytes (Mo) in supporting T cell mitogenesis induced by both mitogens during and after IgG infusion. This reduced cooperative capability of Mo disappeared at various times after the end of therapy (range 3-12 days). The transient alteration of Mo function, possibly due to a modification in the surface number or in the affinity of Fc-receptors, can explain in part, the increase in platelet count during and after IgSRK infusion.