Cell migration, shape maintenance, and intracellular signaling are closely linked to dynamic changes in cell morphology and the cytoskeleton. These processes involve the reorganization of the cytoskeleton within the cytoplasm, affecting all its key components: intermediate filaments, microtubules, and microfilaments. A promising strategy for remotely controlling cellular functions is the use of magnetic nanoparticles, which can influence cellular physiology. This approach, known as magnetogenetics, has been applied in various areas of cell and molecular biology. Applying a magnetic field allows for the non-invasive modulation of biochemical processes, cell migration, and morphological changes in cells containing magnetic nanoparticles. In our study, magnetic nanoparticles were conjugated with antibodies targeting cytoskeletal components, enabling the magnetically induced manipulation and deformation of the cell cytoskeleton. Our research introduces a novel approach to manipulating specific cytoskeletal components and altering cell polarity with spatial precision in vitro using magnetic nanoparticles associated with the cytoskeleton.

Injectable calcium–magnesium phosphate cements (CMPC) represent promising materials for bone defect reconstruction due to their bioresorbability, osteoconductivity, and potential to release biologically active Mg²⁺ ions. In this study, injectable CMPCs based on powders containing 20 and 60 mol.% Mg²⁺ were developed using a sodium phosphate solution containing carboxymethylcellulose (CMC) as the cement liquid. The effects of Mg²⁺ content and CMC incorporation on the physicochemical, handling, in vitro, and in vivo properties of the cements were systematically evaluated. CMC acted primarily as a rheology modifier and structuring agent, improving paste cohesion and injectability while maintaining compressive strength suitable for bone substitution. The developed cements demonstrated controlled degradation accompanied by sustained Mg²⁺ release and showed no cytotoxic effects toward MG-63 cells. Biological studies demonstrated favorable cellular responses and osteogenic potential of the developed materials. Importantly, the cement containing the higher Mg²⁺ concentration and CMC demonstrated the most favorable bone defect regeneration outcomes among the investigated formulations, as evidenced by the restoration of mineralized structures observed by micro-CT and the histological identification of newly formed bone tissue. These findings demonstrate that combining increased Mg²⁺ content with CMC-mediated control of cement handling properties is a promising strategy for developing injectable bioactive bone substitutes.