BRILLIANT CRESYL BLUE

Blood smears examination for reticulocytes. Brilliant cresyl blue is more used in hematology laboratories than in histology laboratories. It is invaluable for the staining of reticulocytes whereas its use in histology is limited to vital staining. Reticulocytes are juvenile red cells, which contain remnants of basophilic ribonucleoproteins. This material reacts with brilliant cresyl blue to form a bluish black precipitate of granules or filaments. The most immature reticulocytes have the largest amount of precitable material. In the least immature only a few dots or short strands are seen. As the number of reticulocytes in the peripheral blood is a measure of erythropoietic activity, a reticulocyte count is one of the essential procedures of diagnostic haematology.