Exosome-Mediated eCIRP Release From Macrophages to Induce Inflammation in Sepsis

Extracellular cold-inducible RNA-binding protein (eCIRP) is an important damage-associated molecular pattern (DAMP). Despite our understanding of the potentially harmful effects of eCIRP in sepsis, how eCIRP is released from cells remains elusive. Exosomes are endosome-derived extracellular vesicles, which carry proteins, lipids, and nucleic acids to facilitate intercellular communication and several extracellular functions. We hypothesized that eCIRP is released via exosomes to induce inflammation in sepsis. Exosomes isolated from the supernatants of LPS-treated macrophage culture and serum of endotoxemia and polymicrobial sepsis mice showed high purity, as revealed by their unique median sizes ranging between 70 and 126 nm in diameter. eCIRP levels of the exosomes were significantly increased after LPS treatment in the supernatants of macrophage culture, mouse serum, and cecal ligation and puncture (CLP)-induced sepsis mouse serum. Protease protection assay demonstrated the majority of eCIRP was present on the surface of exosomes. Treatment of WT macrophages and mice with exosomes isolated from LPS-treated WT mice serum increased TNFα and IL-6 production. However, treatment with CIRP−/- mice serum exosomes significantly decreased these levels compared with WT exosome-treated conditions. CIRP−/- mice serum exosomes significantly decreased neutrophil migration in vitro compared with WT exosomes. Treatment of mice with serum exosomes isolated from CIRP−/- mice significantly reduced neutrophil infiltration into the peritoneal cavity. Our data suggest that eCIRP can be released via exosomes to induce cytokine production and neutrophil migration. Thus, exosomal eCIRP could be a potential target to inhibit inflammation.

Enhanced Skin Incisional Wound Healing With Intracellular ATP Delivery via Macrophage Proliferation and Direct Collagen Production

This study sought to use a newly developed intracellular ATP delivery to enhance incisional wound healing to reduce surgical wound dehiscence and to explore possible mechanism for this effect. Thirty-five adult New Zealand white rabbits were used. Skin incisions were made on the back and closed. ATP-vesicles were mixed with a neutral cream for one side of the wounds while the neutral cream alone was used on the other side of the wounds. Laser speckle contrast imaging (LSCI), biomechanical, histological, and immunohistochemical analyses were performed 7 and 14 days after surgery, and macrophage culture was used to test the enhanced collagen production ability. Among them, 10 were used for wound perfusion study and 25 were used for wound biomechanical and histological/immunohistochemical studies. Wound tissue perfusion was reduced after surgery especially in early days. Wound tissue tensile strength, breaking stress, and elasticity were all much higher in the ATP-vesicle treated group than in the cream treated group at days 7 and 14. The healing was complemented by earlier macrophage accumulation, in situ proliferation, followed by direct collagen production. The results were further confirmed by human macrophage culture. It was concluded that intracellular ATP delivery enhanced healing strength of incisional wounds via multiple mechanisms.

Biomarkers of Parkinson’s disease in carriers of mutations in the glucocerebrosidase gene

Оценка гексозилсфингозина (HexSph), в крови в настоящее время является чувствительным диагностическим тестом развития болезни Гоше. Мы предположили, что оценка данного метаболита может быть эффективна при выявлении развития болезни Паркинсона (БП) у носителей мутаций в гене GBA (GBA-БП). Концентрация HexSph и ферментативная активность GBA была оценена у пациентов с GBA-БП, бессимптомных носителей мутации в гене GBA, пациентов со спорадической БП (сБП) и в контрольной группе в крови, а также в первичной культуре культивируемых макрофагов. Показано, что оценка уровня HexSph в первичной культуре макрофагов позволяет отличить заболевших БП носителей мутаций в гене GBA, от бессимптомных носителей мутаций и может быть рассмотрена как биомаркер развития БП у носителей мутаций в гене GBA. Assessment of hexosylsphingosine (HexSph) in the blood is currently a sensitive diagnostic test for Gaucher disease. We suggested that the assessment of this metabolite may be effective in detecting the development of Parkinson’s disease (PD) in mutation carriers in the GBA gene (GBA-PD). In the present study HexSph concentration and GBA enzymatic activity were evaluated in patients with GBA-BP, asymptomatic carriers of GBA mutations, patients with sporadic PD (sPD) and the control group in blood, as well as in the primary culture of macrophages. An assessment of HexSph level in the primary macrophage culture makes it possible to distinguish GBA mutation carriers with PD from asymptomatic mutation carriers, and though could be considered as a biomarker of PD development in carriers of GBA mutations.