Inflammation biomarkers in the intracranial blood are associated with outcome in patients with ischemic stroke.

BACKGROUND: Performing endovascular treatment (EVT) in patients with acute ischemic stroke (AIS) allows a port of entry for intracranial biological sampling. OBJECTIVE: To test the hypothesis that specific immune players are molecular contributors to disease, outcome biomarkers, and potential targets for modifying AIS. METHODS: We examined 75 subjects presenting with large vessel occlusion of the anterior circulation and undergoing EVT. Intracranial blood samples were obtained by microcatheter aspiration, as positioned for stent deployment. Peripheral blood samples were collected from the femoral artery. Plasma samples were quality controlled by electrophoresis and analyzed using a Mesoscale multiplex for targeted inflammatory and vascular factors. RESULTS: We measured 37 protein biomarkers in our sample cohort. Through multivariate analysis, adjusted for age, intravenous thrombolysis, pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT scores, we found that post-clot blood levels of interleukin-6 (IL-6) were significantly correlated (adjusted P value <0.05) with disability assessed by the modified Rankin Scale (mRS) score at 90 days, with medium effect size. Chemokine (C-C) ligand 17 CCL17/TARC levels were inversely correlated with the mRS score. Examination of peripheral blood showed that these correlations did not reach statistical significance after correction. Intracranial biomarker IL-6 level was specifically associated with a lower likelihood of favorable outcome, defined as a mRS score of 0-2. CONCLUSIONS: Our findings show a signature of blood inflammatory factors at the cerebrovascular occlusion site. The correlations between these acute-stage biomarkers and mRS score outcome support an avenue for add-on and localized immune modulatory strategies in AIS.

Favorable revascularization therapy in patients with ASPECTS ≤ 5 on DWI in anterior circulation stroke.

BACKGROUND: A low baseline Alberta Stroke Programme Early CT Score (ASPECTS) is strongly associated with low rates of favorable outcome in patients with acute stroke. OBJECTIVE: To evaluate the efficacy and safety of revascularization therapy in patient with ASPECTS ≤5 in anterior circulation infarct. METHODS: We retrospectively analyzed 108 consecutive patients presenting low ASPECTS on diffusion-weighted imaging. Sixty patients were treated by mechanical thrombectomy, including 34 patients who received simultaneously intravenous thrombolysis. A control group of 48 patients not eligible for reperfusion therapy gave us a perspective on the natural history. Clinical outcome was evaluated at 90 days using the modified Rankin Scale (mRS) score. Hemicraniectomy after malignant infarction, mortality, and symptomatic intracranial haemorrhage (sICH) were also reported. RESULTS: Thrombolysis in Cerebral Infarction 2b-3 was assessed in 75% of treated patients. Reperfusion therapy led to significantly reduced disability (mRS score 0-2) at 90 days compared with the control group (30% vs 2.1%, p<0.001), hemicraniectomy (3.3% vs 22.9%, p=0.002), and death at 90 days (25% vs 47.9%, p=0.01). The sICH level was similar in treated patients and in the control group (p=0.78). Patients aged ≤70 years in the thrombectomy group had a significantly better clinical outcome than older patients (37.5% vs 10%, p=0.02), regardless of baseline characteristics or recanalization rate. CONCLUSIONS: In patients with acute stroke in the anterior circulation and ASPECTS ≤5 revascularization therapy contributes to a favorable clinical outcome at 90 days, especially in patients younger than 70 years.

Characterization of a synthetic anionic vector for oligonucleotide delivery using in vivo whole body dynamic imaging.

PURPOSE: To compare the pharmacokinetics and bioavailability of an oligonucleotide delivered in a free form or using cationic or anionic synthetic carrier systems. METHODS: Whole body dynamic quantitative imaging and metabolism of a HIV antisense oligonucleotide intravenously administered either free or incorporated into synthetic carriers were compared in baboons. using non invasive positron emission tomography and an enzyme-based competitive hybridization assay, respectively. RESULTS: In its free form, the oligonucleotide showed high liver and kidney concentration, rapid plasmatic degradation and elimination from the body. Use of a cationic vector slightly protected the oligonucleotide against degradation and enhanced uptake by the reticulo-endothelial system. In contrast, the anionic vector dramatically enhanced the uptake in several organs, including the lungs, spleen and brain, with a prolonged accumulation of radioactivity in the brain. Using this vector, intact oligonucleotide was detected in plasma for up to two hours after injection. and the T 1/2beta and distribution volume increased by 4- and 7-fold, respectively. No evidence of toxicity was found after a single dose administration. CONCLUSIONS: The anionic vector improves significantly the bioavailability and the pharmacokinetics of the oligonucleotide, and is a promising delivery system for in vivo administration of therapeutic nucleic acids.

Intranasal immunization with recombinant antigens associated with new cationic particles induces strong mucosal as well as systemic antibody and CTL responses.

New cationic nanoparticles (SMBV) were evaluated for use as a nasal vaccine delivery system for two recombinant proteins: HBsAg and beta-galactosidase. Each protein was formulated with SMBV and intranasally administrated to non-anesthetized mice. In each model, the formulated protein induced high levels of specific serum IgG antibodies and cytotoxic T lymphocyte (CTL) responses. Moreover, specific IgA antibodies were found in nasal as well as in vaginal washes of intranasally immunized mice with the protein associated with SMBV. In contrast, no IgG or IgA antibodies and no CTL were detected in mice immunized with free protein. The detection of a CTL response and an increase in both IgG1 and IgG2a antibodies in serum suggest that SMBV amplifies both Th1 and Th2 responses without modifying the Th1/Th2 profile of the immune response induced by the natural protein. These data demonstrate the high potential of SMBV for use as a nasal delivery system for sub-unit vaccines.

Characterization of humoral and cellular immune responses in mice induced by immunization with HIV-1 Nef regulatory protein encapsulated in poly(DL-lactide-co-glycolide) microparticles.

We have characterized the humoral and cellular immune responses of BALB/c mice immunized with HIV-1 Nef regulatory protein encapsulated in poly(DL-lactide-co-glycolide) PLG particles. Three groups of mice were immunized with Nef PLG, Nef in the presence of complete Freund's adjuvant (CFA) or Nef alone in PBS. When titers were compared 7 months after the last injection, anti-Nef titers in mice immunized with Nef PLG were still close to the maximum, whereas a significant decrease was observed in mice immunized with Nef alone (five times lower) or with Nef in CFA (three times lower). These results indicate that Nef PLG is at least a similar or better vector/adjuvant than Nef in CFA concerning the duration of the humoral immune response. The analysis of cytokine profiles (IL-5 and IL-10) and the isotypic patterns of anti-Nef antibodies (predominantly IgG1), in the three groups of mice, indicated a predominant Th2 immune response. Using synthetic peptides covering the entire sequence of Nef, we identified at least three linear epitopes within sequences 32-64, 118-167 and 185-205 in the sera of mice immunized with Nef PLG or Nef CFA. In contrast, anti-Nef antibodies against Nef alone failed to recognize synthetic peptides, indicating that the majority of anti-Nef antibodies were primarily directed against conformational epitopes. We then examined the ability of Nef PLG to prime for the antigen-specific proliferative responses in vitro. The data obtained indicate the presence of both B-cell and T-cell epitopes in the C-terminal fragment of the protein after immunization of mice with Nef encapsulated in PLG particles.