Biomaterial Database

Venous Air Embolism Activates Complement C3 Without Corresponding C5 Activation and Trigger Thromboinflammation in Pigs. 2022

Benjamin S Storm, and Judith K Ludviksen, and Dorte Christiansen, and Hilde Fure, and Kristin Pettersen, and Anne Landsem, and Bent Aksel Nilsen, and Knut Dybwik, and Tonje Braaten, and Erik W Nielsen, and Tom E Mollnes

Department of Anesthesia and Intensive Care Medicine, Nordland Hospital, Bodø, Norway.

Air embolism may complicate invasive medical procedures. Bubbles trigger complement C3-mediated cytokine release, coagulation, and platelet activation in vitro in human whole blood. Since these findings have not been verified in vivo, we aimed to examine the effects of air embolism in pigs on thromboinflammation. Forty-five landrace pigs, average 17 kg (range 8.5-30), underwent intravenous air infusion for 300 or 360 minutes (n=29) or served as sham (n=14). Fourteen pigs were excluded due to e.g. infections or persistent foramen ovale. Blood was analyzed for white blood cells (WBC), complement activation (C3a and terminal C5b-9 complement complex [TCC]), cytokines, and hemostatic parameters including thrombin-antithrombin (TAT) using immunoassays and rotational thromboelastometry (ROTEM). Lung tissue was analyzed for complement and cytokines using qPCR and immunoassays. Results are presented as medians with interquartile range. In 24 pigs receiving air infusion, WBC increased from 17×109/L (10-24) to 28 (16-42) (p<0.001). C3a increased from 21 ng/mL (15-46) to 67 (39-84) (p<0.001), whereas TCC increased only modestly (p=0.02). TAT increased from 35 µg/mL (28-42) to 51 (38-89) (p=0.002). ROTEM changed during first 120 minutes: Clotting time decreased from 613 seconds (531-677) to 538 (399-620) (p=0.006), clot formation time decreased from 161 seconds (122-195) to 124 (83-162) (p=0.02) and α-angle increased from 62 degrees (57-68) to 68 (62-74) (p=0.02). In lungs from pigs receiving air compared to sham animals, C3a was 34 ng/mL (14-50) versus 4.1 (2.4-5.7) (p<0.001), whereas TCC was 0.3 CAU/mL (0.2-0.3) versus 0.2 (0.1-0.2) (p=0.02). Lung cytokines in pigs receiving air compared to sham animals were: IL-1β 302 pg/mL (190-437) versus 107 (66-120), IL-6 644 pg/mL (358-1094) versus 25 (23-30), IL-8 203 pg/mL (81-377) versus 21 (20-35), and TNF 113 pg/mL (96-147) versus 16 (13-22) (all p<0.001). Cytokine mRNA in lung tissue from pigs receiving air compared to sham animals increased 12-fold for IL-1β, 121-fold for IL-6, and 17-fold for IL-8 (all p<0.001). Venous air embolism in pigs activated C3 without a corresponding C5 activation and triggered thromboinflammation, consistent with a C3-dependent mechanism. C3-inhibition might represent a therapeutic approach to attenuate this response.

UI	MeSH Term	Description	Entries
D007249	Inflammation	A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.	Innate Inflammatory Response,Inflammations,Inflammatory Response, Innate,Innate Inflammatory Responses
D003176	Complement C3	A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.	C3 Complement,C3 Precursor,Complement 3,Complement C3 Precursor,Complement Component 3,Precursor-Complement 3,Pro-C3,Pro-Complement 3,C3 Precursor, Complement,C3, Complement,Complement, C3,Component 3, Complement,Precursor Complement 3,Precursor, C3,Precursor, Complement C3,Pro C3,Pro Complement 3
D004618	Embolism, Air	Blocking of a blood vessel by air bubbles that enter the circulatory system, usually after TRAUMA; surgical procedures, or changes in atmospheric pressure.	Air Embolism,Embolism, Gas,Air Embolisms,Embolisms, Air,Embolisms, Gas,Gas Embolism,Gas Embolisms
D000090882	Thromboinflammation	Thrombosis with associated inflammation due to crosstalk between HEMOSTASIS and INNATE IMMUNE RESPONSES modulated by PLATELETS. It is associated with many diseases such as COVID-19; SICKLE CELL ANEMIA; and THROMBOPHLEBITIS.	Immunothrombosis
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog
D013927	Thrombosis	Formation and development of a thrombus or blood clot in BLOOD VESSELS.	Atherothrombosis,Thrombus,Blood Clot,Blood Clots,Thromboses
D015850	Interleukin-6	A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.	Hepatocyte-Stimulating Factor,Hybridoma Growth Factor,IL-6,MGI-2,Myeloid Differentiation-Inducing Protein,Plasmacytoma Growth Factor,B Cell Stimulatory Factor-2,B-Cell Differentiation Factor,B-Cell Differentiation Factor-2,B-Cell Stimulatory Factor 2,B-Cell Stimulatory Factor-2,BSF-2,Differentiation Factor, B-Cell,Differentiation Factor-2, B-Cell,IFN-beta 2,IL6,Interferon beta-2,B Cell Differentiation Factor,B Cell Differentiation Factor 2,B Cell Stimulatory Factor 2,Differentiation Factor 2, B Cell,Differentiation Factor, B Cell,Differentiation-Inducing Protein, Myeloid,Growth Factor, Hybridoma,Growth Factor, Plasmacytoma,Hepatocyte Stimulating Factor,Interferon beta 2,Interleukin 6,Myeloid Differentiation Inducing Protein,beta-2, Interferon
D015938	Complement Membrane Attack Complex	A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.	Complement Complex C5b-9,Membrane Attack Complex,C 5b-9,C5b-8-poly-C9,C5b-9,Cytolytic Terminal Complement Complex,Terminal Complement Complex,C5b 8 poly C9,Complement Complex C5b 9,Complement Complex, Terminal,Complex, Terminal Complement
D016207	Cytokines	Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.	Cytokine