Effects of centrifugation and whole-body vibrations on blood-brain barrier permeability in mice
NPJ MICROGRAVITY
Authors: Dubayle, David; Vanden-Bossche, Arnaud; Beraneck, Mathieu; Vico, Laurence; Morel, Jean-Luc
Abstract
Modifications of gravity levels induce generalized adaptation of mammalian physiology, including vascular, brain, muscle, bone and immunity functions. As a crucial interface between the vascular system and the brain, the blood-brain barrier (BBB) acts as a filter to protect neurons from pathogens and inflammation. Here we compare the effects of several protocols of hypergravity induced by centrifugation and whole-body vibrations (WBV) on BBB integrity. The immunohistochemistry revealed immunoglobulin G (IgG) extravasation from blood to hippocampal parenchyma of mice centrifuged at 2 x g during 1 or 50 days, whereas short exposures to higher hypergravity mimicking the profiles of spaceflight landing and take-off (short exposures to 5 x g) had no effects. These results suggest prolonged centrifugation (>1 days) at 2 x g induced a BBB leakage. Moreover, WBV were similarly tested. The short exposure to +2 x g vibrations (900 s/day at 90 Hz) repeated for 63 days induced IgG extravasation in hippocampal parenchyma, whereas the progressive increase of vibrations from +0.5 to +2 x g for 63 days was not able to affect the IgG crossing through the BBB. Overall, these results suggest that the BBB permeability is sensitive to prolonged external accelerations. In conclusion, we advise that the protocols of WBV and centrifugation, proposed as countermeasure to spaceflight, should be designed with progressively increasing exposure to reduce potential side effects on the BBB.
Efficacy, Safety, and Immunomodulatory Effect of the Intramuscular Administration of Autologous Total Immunoglobulin G for Atopic Dermatitis: A Randomized Clinical Trial
ALLERGY ASTHMA & IMMUNOLOGY RESEARCH
Authors: Dong-Ho Nahm; Ye, Young-Min; Shin, Yoo Seob; Park, Hae-Sim; Kim, Myoung-Eun; Kwon, Byul; Cho, Su-Mi; Han, Jinjoo
Abstract
Purpose: The management of patients with atopic dermatitis (AD) is often difficult. We hypothesized that repeated intramuscular administration of autologous total immunoglobulin G (IgG) could induce clinical improvement in patients with AD through immune modulation. This clinical trial was conducted to evaluate the efficacy, safety, and immunomodulatory effect of the intramuscular administration of autologous total IgG in patients with AD. Methods: In this randomized, double-blind, placebo-controlled trial, 51 adolescent and adult patients with moderate-to-severe AD were randomized to receive 8 weekly intramuscular administrations of autologous total IgG 50 mg (n = 26) or saline (n = 25) over a 7-week period and were followed up to week 16. Changes in the clinical severity score (Eczema Area and Severity Index), affected body surface area, patient-reported Dermatology Life Quality Index (DLQI) score, laboratory biomarkers, and incidence of adverse events from baseline to week 16 were assessed. Results: The intramuscular administration of autologous total IgG, compared with saline, decreased the clinical severity score (-64.8% vs. -20.3%, P < 0.001), reduced the affected body surface area (-53.9% vs. -19.1%, P < 0.001), improved the DLQI score (-35.4% vs. -14.4%, P = 0.015), increased serum interleukin-10 and interferon-. levels ( P = 0.011 and P = 0.003, respectively), and reduced the incidence of AD exacerbation (11.5% vs. 48.0%, P = 0.004) from baseline to week 16. No serious adverse events were observed. Conclusions: The intramuscular administration of autologous total IgG provided clinical improvements and a systemic immunomodulatory effect in adolescent and adult patients with moderate-to-severe AD without significant side effects.