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Aim and Background:
The aim of this study was to enhance the synergistic effect of the "RA-FICZ" by adding anti CD44 monoclonal antibody (mAb), to induce myeloid differentiation and apoptosis in three patients with APL.
Materials and methods:
The anti-CD44 antibody concentrations of 5 to 25 μg/ml prepared and added to "RA-FICZ" complex and Isolated Cells from Patients.The antibody optimum concentration was determined then neutrophil maturation, apoptosis and expression of CD14 and CD11b were analyzed by flow cytometry.
Results:
Adding the different concentrations of CD44 mAb against CD44 improved the ability of promyelocytes differentiation and led to increased expression of CD11b and CD14 antigens more than two times. The apoptotic rate increased up to 66%.
Conclusion:
Additional studies and work on the animal models can lead to a reduction even elimination of the chemotherapy. This triple combination" can be candidate as a novel differentiation-inducing therapy in APL cells.

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Nowadays, design and synthesis of efficient drug delivery systems are of vital importance in order to optimize the efficacy of therapeutics and reducing side effects. So far, many drug delivery systems have been designed, among them, natural polymer-based systems have attracted the most attention. Silk fibroin (SF) as a natural polymer have several unique properties including excellent biocompatibility, biodegradability, good mechanical behavior, ease of processability with ability to fabricate various structures e.g., nanoparticles, microparticles, fibers, hydrogels, films, that makes it a suitable material for biomedical applications especially drug delivery vehicles. In this review, we discuss the drug delivery applications of SF, in detail.