Immunocytochemical study of Bcr and Bcr-Abl localization in K562 cells.

AIM: To obtain polyclonal antibodies against recombinant proteins recognizing Bcr domain and fusion region of Bcr-Abl and analyze the patterns of intracellular distribution of Bcr and Bcr-Abl proteins in K562 cells of chronic myelogenous leukemia.

METHODS

The coding sequences of DH and PH domains of Bcr-Abl were cloned, and the recombinant proteins were expressed in E. coli. The rabbit polyclonal antibodies were produced and used for immunocytochemical study of Bcr and Bcr-Abl localization in K562 cells.

RESULTS

The gene constructs containing sequences coding for DH and PH domains of Bcr-Abl have been obtained. The antibodies with relative specificity to corresponding recombinant proteins differ by the patterns of their intracellular reactivity with Bcr- and Bcr-Abl related structures. While Bcr protein is located predominantly perinuclearly, antibody against hybrid Bcr-Abl protein is reacted with the structures in cell periphery, namely on cell membranes.

CONCLUSION

Antibodies against DH and PH domains of Bcr-Abl react with proteins located differently in chronic myelogenous leukemia cells. The difference in intracellular localization of Bcr and Bcr-Abl may be attributable to the different domains interacting with different multiprotein complexes.