Liposome-based nanoparticles impact on regulatory and effector phenotypes of macrophages and T cells in multiple Sclerosis patients.

Current available treatments of Multiple Sclerosis (MS) reduce neuroinflammation acting on different targets on the immune system, but potentially lead to severe side effects and have a limited efficacy in slowing the progression of the disease. Here, we evaluated in vitro the immunomodulatory potential of a new class of nanoparticles - liposomes, constituted by a double-layer of phosphatidylserine (PSCho/PS), and double-faced, with an outer layer of phosphatidylserine and an inner layer of phosphatidic acid (PSCho/PA), either alone or in the presence of the myelin basic protein (MBP) peptide (residues 85-99) (PSCho/PS-MBP and PSCho/PA-MBP). Results showed that PSCho/PS are equally and efficiently internalized by pro- and anti-inflammatory macrophages (M1 and M2 respectively), while PSCho/PA were internalized better by M2 than M1. PSCho/PS liposomes were able to inhibit the secretion of innate pro-inflammatory cytokine IL-1ß. PSCho/PS liposomes expanded Tregs, reducing Th1 and Th17 cells, while PSCho/PA liposomes were unable to dampen pro-inflammatory T cells and to promote immune-regulatory phenotype (Treg). The ability of PSCho/PS liposomes to up-regulate Treg cells was more pronounced in MS patients with high basal expression of M2 markers. PSCho/PS liposomes were more effective in decreasing Th1 (but not Th17) cells in MS patients with a disease duration >3 months. On the other hand, down-modulation of Th17 cells was evident in MS patients with active, Gadolinium enhancing lesions at MRI and in MS patients with a high basal expression of M1-associated markers in the monocytes. The same findings were observed for the modulation of MBP-driven Th1/Th17/Treg responses. These observations suggest that early MS associate to a hard-wired pro-Th1 phenotype of M1 that is lost later during disease course. On the other hand, acute inflammatory events reflect a temporary decrease of M2 phenotype that however is amenable to restauration upon treatment with PSCho/PS liposomes. Thus, together these data indicate that monocytes/macrophages may play an important regulatory function during MS course and suggest a role for PSCho/PS and PSCho/PS-MBP as new therapeutic tools to dampen the pro-inflammatory immune responses and to promote its regulatory branch.

Exit strategies for "needle fatigue" in multiple sclerosis: a propensity score-matched comparison study.

Patients with multiple sclerosis on long-term injectable therapies may suffer from the so-called "needle fatigue", i.e., a waning commitment to continue with the prescribed injectable treatment. Therefore, alternative treatment strategies to enhance patients' adherence are warranted. In this independent, multicentre post-marketing study, we sought to directly compare switching to either teriflunomide (TFN), dimethyl fumarate (DMF), or pegylated interferon (PEG) on treatment persistence and time to first relapse over a 12-month follow-up. We analyzed a total of 621 patients who were free of relapses and gadolinium-enhancing lesions in the year prior to switching to DMF (n = 265), TFN (n = 160), or PEG (n = 196). Time to discontinuation and time to first relapse were explored in the whole population by Cox regression models adjusted for baseline variables and after a 1:1:1 ratio propensity score (PS)-based matching procedure. Treatment discontinuation was more frequent after switching to PEG (28.6%) than DMF (14.7%; hazard ratio [HR] = 0.25, p < 0.001) and TFN (16.9%; HR = 0.27, p < 0.001). We found similar results even in the re-sampled cohort of 222 patients (74 per group) derived by the PS-based matching procedure. The highest discontinuation rate observed in PEG recipient was mainly due to poor tolerability (p = 0.005) and pregnancy planning (p = 0.04). The low number of patients who relapsed over the 12-month follow-up (25 out of 621, approximately 4%) prevented any analysis on the short-term risk of relapse. This real-world study suggests that oral drugs are a better switching option than low-frequency interferon for promoting the short-term treatment persistence in stable patients who do not tolerate injectable drugs.