Allogeneic tissue transplantation is one of the most effective treatments for several diseases and injuries, in particular, malignant and non-malignant hematological conditions. Following this procedure, transplanted tissue encounters various complications, one of the most serious being graft-versus-host disease (GvHD).The management of GvHD directly affects the success of transplantation and the survival rate of the patient; therefore, many studies have focused on GvHD prevention and control. This review briefly explains the transplantation process, causes of graft rejection, and importance of the human leukocyte antigen system.Initially, we address the pathophysiology and immunobiology of GvHD, the cells involved in this complication, the differences between chronic and acute GvHD, and the importance of graft-versusleukemia. Interestingly, various types of immune cells are involved in GvHD pathogenesis. After explaining how these cells affect the GvHD process, we discuss the studies conducted to control and reduce GvHD symptoms.

This work investigates the synergistic effect of magnetotherapy and a novel cationic−magnetic drug delivery system on inhibiting breast cancer cell growth and other tissues. First, super-paramagnetic magnetite (Fe 3 O 4 ) nanoparticles were coated with doxorubicin-imprinted poly(methacrylic acid-co-diallyl dimethylammonium chloride) [Fe 3 O 4 /poly(MAA-DDA)]. The cationic−magnetic nanocomposite (CMC) was characterized using XRD, FT-IR, VSM, TGA, TEM, FESEM, EDS, DLS, and BET. In vitro analyses, including drug release kinetics, cytotoxicity, and hemolytic assays, confirmed this novel CMC's good drug release profile and biocompatibility. Finally, in vivo experiments on BALB/c mice were designed to evaluate the synergistic effect of magnetotherapy on targeted drug delivery using the CMC. In vivo fluorescence imaging evaluated the drug distribution in different tissues of mice. Tumor volume evaluation demonstrated the efficiency of the CMC and magnetotherapy in preventing tumor growth; the two techniques significantly reduced tumor volume. Histopathological analysis proved that applying magnetotherapy in conjunction with the cationic−magnetic drug delivery system significantly prevented tumor cell proliferation and increased apoptosis with limited impact on other tissues. Also, Dox and Fe concentrations in different tissues confirmed the efficient drug delivery to tumor cells.