BrdU related direct revelation of typical dynamic R- and G-banding with the use of monoclonal anti-BrdU antibody.

Pulse 5-bromodeoxyuridine (5-BrdU) incorporation during the last S-phase is known to produce R- or G-banded chromosomes after photolysis-plus-Giemsa (FPG) staining. The authors applied an immunological staining with monoclonal anti-BrdU antibody instead of the FPG protocol. The results offered banded chromosomes with an immunological typical R-banding (RBI) on the GBG cultivated cells (early pulse incorporation), and an immunological G-banding (GBI) on the RBG cultivated ones (late pulse incorporation). After a further FPG protocol following an immunological treatment, an inverted banding pattern became evident whereas a faint immunological staining remained. Thus the method superimposed a GBG-banding on the RBI-staining or a RBG on the GBI one. This allows a rapid and easy R and G double chromosomal identification on the same metaphase cell, using first the immunological banding then the classical FPG staining. The method allows a reproducible dynamic G-banding with an easy monitored late 5-BrdU pulse incorporation specially attractive in spontaneous dividing cells from bone marrow. This dynamic G-banding protocol should be extended to chorionic villi and malignant cells. Our data are in agreement with a connection between dynamic banding and chromosomal portions containing or not BrdU. The lack of an immunological staining after the FPG protocol has been noticed and assume the photolysis degradation-elution of the DNA in BrdU-substituted areas.