We assessed the safety and clinical effectiveness of intranasal therapy with M2 macrophage-derived soluble products (M2-SPs) for treating patients with cerebrovascular disease (CVD).

The protocol of the study was registered at www.ClinicalTrails.gov (NCT02957123). The study group comprised 30 patients with chronic CVD. Neurological status was examined before therapy and at 1- and 6-month follow–up. Concentrations of 32 cytokines in the blood serum were evaluated before and 1 month after therapy onset. Neurological assessment was conducted with the following scales: Subjective Assessment of Clinical (neurological) Symptoms (SACS), Hospital Anxiety and Depression Scale (HADS), Functional Mobility Assessment in Eldery Patients (FMA), and Montreal Cognitive Assessment (MoCa).

M2-SPs treatment (once daily for 28~30 days) was found to be safe and well tolerated. Neuropsychological improvements showed the amelioration of neurological symptoms, reduction in anxiety and depression levels, improvement in balance and gait ability as well as cognitive functions. Clinical effects could be detected at the end of treatment course and was stable during 6-month follow-up. Blood serum cytokine evaluation demonstrated diminished baseline levels of many cytokines including those with neurotrophic activity (brain-derived neurotrophic factor, BDNF; hepatocyte growth factor, HGF; migration inhibitory factor, MIF). Upon treatment, most pronounced clinical responses were observed in patients with most severe cytokine deficiency and post-therapy normalization of MIF and HGF levels.

Intranasal therapy with M2-SPs is safe and according to preliminary data reduces neuropsychological deficit in patients with chronic CVD. The positive effect of M2-SPs treatment seems to be HGF- and MIF-dependent.

Cell-based technologies are considered to be a new approach for the treatment of cerebral palsy (CP). Given the potent anti-inflammatory activity and high regenerative potential of M2 macrophages, these cells may be a promising source for cell transplantation. To evaluate the safety and efficacy of autologous M2 macrophages, we performed an open-label, Phase I/II, non-controlled clinical trial in children with severe CP.

Fifty-seven children with severe CP, including 33 boys and 24 girls, with a median age of 4 years were enrolled in the study. The patients were treated with intrathecal administration of autologous M2 macrophages. The primary outcome measure was safety, and the secondary outcome measure was functional improvement in neurologic scales, including the 66-item Gross Motor Function Measure test, Peabody Developmental Motor Scale-Fine Motor test, Ashworth scale, Medical Resarch Council scale, and an easy-to-understand unified questionnaire for evaluation of cognitive functions in our modification.

Intrathecal introduction of M2 cells in a median dose of 11.2×10⁶ did not induce any serious adverse events either related with cell injection or during 5 years of follow-up. After 3 months, the Gross Motor Function Measure score increased from 19±4.5 to 77±7.8, the Peabody Developmental Motor Scale-Fine Motor test score improved from 0.9±0.23 to 4.4±0.51, and the Ashworth score decreased from 3.5±0.11 to 2.5±0.16. The assessment of cognitive functions revealed an increase from 1.22±0.24 to 3.98±0.95, and a reduction of seizure syndrome was registered. In addition, M2 injection was accompanied by an increased production of brain-derived neurotrophic factor (p_U=0.015).

The data obtained suggest that cell therapy based on M2 macrophages is safe, does not induce any severe cell-related reactions or long-term side effects and comorbidities, and is accompanied by significant neurologic improvements in severe CP patients.