The significance of Ki-67, BrdU and OKT9 expression in determination of myelodysplastic syndromes by use of APAAP technique.

Monoclonal antibodies (McAb) to Ki-67, BrdU and OKT9 were used in APAAP technique for determining the proliferative cells of 46 myelodysplastic syndromes (MDS) with 16 serving as normal controls. According to Ki-67 positive labelling, the proliferative fractions of bone marrow cells can be divided into low (< 25%), intermediate (25%-35%), and high (> 35%) grades. The labelling positivity of Ki-67, BrdU and OKT9 in MDS was all higher than that of the controls. Furthermore, the positive percentages of these three McAbs were significantly correlated. From the results of our experiment, an increase in proliferative fraction was related to clinical classification, prognosis, and therapy of MDS. On the other hand, the positive percentage of Ki-67 > 40% and BrdU > 30% or ratio of BrdU to Ki-67 > 80% may be considered as parameters for unfavourable prognosis.