In recent years, there has been a tremendous development of biotechnological, pharmacological, and medical techniques which can be implemented in the functional modulation of the immune system components. Immunomodulation has attracted much attention because it offers direct applications in both basic research and clinical therapy. Modulation of a non-adequate, amplified immune response enables to attenuate the clinical course of a disease and restore homeostasis. The potential targets to modulate immunity are as multiple as the components of the immune system, thus creating various possibilities for intervention. However, immunomodulation faces new challenges to design safer and more efficacious therapeutic compounds. This review offers a cross-sectional picture of the currently used and newest pharmacological interventions, genomic editing, and tools for regenerative medicine involving immunomodulation. We reviewed currently available experimental and clinical evidence to prove the efficiency, safety, and feasibility of immunomodulation in vitro and in vivo. We also reviewed the advantages and limitations of the described techniques. Despite its limitations, immunomodulation is considered as therapy itself or as an adjunct with promising results and developing potential.

Parkinson's disease (PD) is a neurodegenerative disease that is an increasing threat to an aging society. The idiopathic form of PD accounts for over 90% of all cases, and the current etiology is still unknown. One of the reasons hindering research on this form of PD is the lack of an appropriate animal models. Among mouse models of the disease, those based on the administration of neurotoxins such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 6-hydroxydopamine (6-OHDA) to the substantia nigra pars compacta (SNpc) or striatum are predominantly used. In these models, there are metabolic disturbances causing oxidative stress in the SNpc or striatum, which ultimately leads to the death of dopaminergic neurons. However, the models used so far have serious limitations, most of all they do not fully reflect the processes occurring in the course of the disease and do not consider the involvement of inflammation in the etiology and pathogenesis of PD. In this study we show that the administration of synthetic neuromelanin, which activates astrocytes and microglia, induces the inflammation and may be involved in degeneration of dopaminergic neurons. Neuromelanin under physiological conditions acts as a neuroprotector, however, released from dying dopaminergic neurons is an important factor activating astrocytes, microglia and causing neuroinflammation. Since one of the causes of Parkinson's appear to be the death of dopaminergic neurons overloaded with neuromelanin and consequent pathological activation of microglia, the use of synthetic neuromelanin reflect the natural pathological processes occurring during the development of the disease.