Immune Complexes in Myeloproliferative Disorders

Cellular Abnormalities and Reduced Colony-Forming Cells in Chronic Neutrophilic Leukaemia

“…The discrepancy between these results and normal ultra structure could be due to a heterogeneous population of platelets. One possible mechanism of storage pool deficiency is recirculation of platelets that have re leased part of their contents [10,11] and this release could be induced by immune complexes [12] and granulocytic proteases [13] which may be present in CNL. The other possibility is the production of defec tive platelets from an abnormal megakaryocyte pre cursor.…”

The Association between Autoimmunity and Agnogenic Myeloid Metaplasia

“…This disease preceded the overt manifestation of AMM by 3 years and was characterized by neuropathy, arthritis, scleroderma-like features, the presence of autoantibodies to peripheral nerve, acetylcholine receptor and nuclear antigens and by cryoglobulins. It seems that AMM is not infrequently accompanied or preceded by a Coombs' positive haemolytic anaemia (1,12,13), by a positive tests for rheumatoid factor and LE cells (14)(15)(16), by anti-organ antibodies (16), by circulating immune complexes (17) and by cryoglobulinaemia (12). In addition, a few patients with AMM associated with SLE or scleroderma have been described (18,19).…”

Platelet Fc Receptor

“…Membrane receptors for peptide hormones may be regulated by the ambient concentration of the specific hormone (29). Circulating immune complexes, which are present in some patients with myeloproliferative disease (11), may elicit the expression of a specific population of platelet Fc receptors. It is of some interest that in preliminary studies, six of seven myeloproliferative patients reported in this study with >80% platelet staining by the immune complex ovalbumin-anti-ovalbumin also had elevated circulating immune complexes (30).…”

“…Circulating immune complexes have been reported in the plasma of patients with myelofibrosis (11). Immune complexes may interfere with platelet func-tion through interaction with a platelet Fe receptor (12,13).…”