Circulating immune complexes in chronic myeloid leukemia: turbidimetric measurement and two-dimensional electrophoretic analysis

Growth factors in chronic myelogenous leukemia

Transforming growth factors (TGFs) are implicated in malignancy, therefore qualitative and quantitative differences of these growth factors in chronic myelogenous leukemia (CML) in chronic phase has been investigated in this report. Induction of anchorage independent growth of BALB/c 3T3 and NRK-49F fibroblasts was used as an assay to detect TGF-beta activity in sera, serum free leukocyte and stromal conditioned medium of CML patients as well as normal subjects. The data shows that enhanced levels of transforming growth factor (type beta like activity) are detectable in the sera of chronic myelogenous leukemia patients. We believe that the enhanced levels of TGF-beta type activity may have a role in myeloid hyperplasia characteristic of CML patients in chronic phase of the disease.

Circulating immune complexes in chronic myeloid leukemia: studies on 37 K protein antigen

The 37 K protein, earlier found to be present in 3.75% PEG-precipitates from sera of untreated patients with CML, was further characterized. Gel filtration at neutral pH resolved the PEG-precipitate into a non-IgG containing protein peak-I and a IgG containing peak-II. Immunoprecipitation of peak-II with antihuman IgG antiglobulin and subsequent 2D-SDS-PAGE analysis of the immunoprecipitate revealed the presence of 37 K protein in peak-II confirming its association with IgG. 125I-37 K protein was found to interact with antibodies isolated from autologous and allogenic CML-CIC samples but not with similarly isolated antibodies from normal subject, and patients with AML, ALL, MF, and HD. Peptide maps generated by tryptic digestion of 37 K protein (from five different CML patients) were found to be identical. Specific interaction of 37 K protein with the autologous and allogenic antibodies and identity of peptide maps lead to the conclusion that the 37 K protein is a CML-associated antigen appearing in CIC.