Results 21 to 30 of about 2,792 (97)

Ultrastructure of cobra venom factor-dependent C3/C5 convertase and its zymogen, factor B of human complement.

Journal of Biological Chemistry, 1982
The molecular architecture of the cobra venom factor (CVF)-dependent C3/C5 convertase (EC 3.4.21.47) of human complement was deduced from electron microscopy of the purified bimolecular complex (CVF,Bb) and its isolated subunits, CVF and Bb. Negatively stained CVF imaged as an irregularly shaped cylindrical structure, with approximate dimensions of 137
C A, Smith, C W, Vogel, H J, Müller-Eberhard   +2 more
openaire   +2 more sources

Complement system part I - molecular mechanisms of activation and regulation

Frontiers in Immunology, 2015
Complement is a complex innate immune surveillance system, playing a key role in defense against pathogens and in host homeostasis. The complement system is initiated by conformational changes in recognition molecular complexes upon sensing danger ...
Nicolas eMerle, Sarah Elizabeth Church, Veronique eFremeaux-Bacchi, Lubka T. Roumenina   +3 more
doaj   +1 more source

Decay accelerating factor (CD55) protects neuronal cells from chemical hypoxia-induced injury

Journal of Neuroinflammation, 2010
Background Activated complement system is known to mediate neuroinflammation and neurodegeneration following exposure to hypoxic-ischemic insults. Therefore, inhibition of the complement activation cascade may represent a potential therapeutic strategy ...
Tsokos George C, Simovic Milomir, Dalle Lucca Shawn L, Li Yansong, Wang Ying, Dalle Lucca Jurandir J   +5 more
doaj   +1 more source

A Cell-Based Assay to Measure the Activity of the Complement Convertases

Kidney International Reports
Introduction: The complement system serves as a crucial defense mechanism against invading pathogens; however, dysregulation of this system can result in harmful consequences.
Małgorzata Stasiłojć, Grzegorz Stasiłojć, Alicja Kuźniewska, Santiago Rodriguez de Córdoba, Marcin Okrój   +4 more
doaj   +1 more source

The lectin pathway of complement activation is a critical component of the innate immune response to pneumococcal infection.

PLoS Pathogens, 2012
The complement system plays a key role in host defense against pneumococcal infection. Three different pathways, the classical, alternative and lectin pathways, mediate complement activation.
Youssif M Ali, Nicholas J Lynch, Kashif S Haleem, Teizo Fujita, Yuichi Endo, Soren Hansen, Uffe Holmskov, Kazue Takahashi, Gregory L Stahl, Thomas Dudler, Umakhanth V Girija, Russell Wallis, Aras Kadioglu, Cordula M Stover, Peter W Andrew, Wilhelm J Schwaeble   +15 more
doaj   +1 more source

Activation of the Lectin Pathway Drives Persistent Complement Dysregulation in Long COVID

Immunology, EarlyView.
The complement cascade, a series of blood proteins that assists in the recognition and neutralisation of pathogens, either independently or in conjunction with antibodies, is persistently activated in patients with long COVID. We found that blood plasma samples from patients with long COVID contained elevated concentrations of the mannan‐binding lectin‐
Samuel B. K. Keat, Priyanka Khatri, Youssif M. Ali, Chanuka H. Arachchilage, Gregory Demopulos, Kirsten Baillie, Kelly L. Miners, Kristin Ladell, Samantha A. Jones, Helen E. Davies, David A. Price, Wioleta M. Zelek, B. Paul Morgan, Wilhelm J. Schwaeble, Nicholas J. Lynch   +14 more
wiley   +1 more source

Complement Hyperactivation Is Mediated by Alternative and Lectin Pathways During Early Phase of Severe Vaccination‐Omicron BA.5 Infection

Journal of Medical Virology, Volume 98, Issue 3, March 2026.
ABSTRACT Complement temporal activation kinetics, activation pathways, and their relationship with thromboinflammation and antibody responses in severe vaccination‐COVID‐19 remains unclear. Based on a vaccinated‐infected cohort, we analyzed complement immune responses across mild to critical COVID‐19 cases by a dynamic model.
Jinpeng Cao, Gang Yang, Tingting Cui, Jian Qin, Deyi Huang, Shiqin Jin, Xiaoyun Yang, Mingzhu Huang, Xiaoling Su, Siyi Liu, Yingjiao Xia, Shidong Deng, Chengna Luo, Zhuxiang Zhao, Yunhui Zhang, Nanshan Zhong, Zhongfang Wang   +16 more
wiley   +1 more source

The fc fragment of IgMs binds C1q to activate the first step of the classical complement pathway, while inhibiting complement‐dependent cytotoxicity

The FEBS Journal, Volume 293, Issue 5, Page 1358-1375, March 2026.
Multimeric IgM‐fragment crystallizable region (Fc) fragments retain the ability to bind C1q and initiate the classical complement pathway, leading to C4 activation and deposition in vitro. However, the Fc cores can also inhibit complement‐dependent cytotoxicity by competing with surface‐bound antibodies for C1q engagement.
Andrea J. Pinto, Anne Chouquet, Isabelle Bally, Véronique Rossi, Nicole M. Thielens, Chantal Dumestre‐Pérard, Renate Kunert, Christine Gaboriaud, Wai Li Ling, Jean‐Baptiste Reiser   +9 more
wiley   +1 more source

The Distribution of Complement Proteins in Soft and Hard Coronas Impacts Macrophage Uptake of Nanoparticles

Advanced Healthcare Materials, Volume 15, Issue 6, 9 February 2026.
Protein corona plays a critical role in the biological behavior of nanoparticles. This study investigates the distribution of complement proteins in soft corona and their impact on the macrophage uptake of polymer nanoparticles. It underlines the significance of soft corona investigation for understanding in vivo performance of nanomedicines.
Ying Qiu, Tianchang He, Chunjie Miao, Xinyang Shi, Yuanyuan Niu, Volker Mailänder, Daniel Crespy, Katharina Landfester, Shuai Jiang   +8 more
wiley   +1 more source

Iptacopan for Immune Thrombocytopenia and Cold Agglutinin Disease: A Global Phase 2 Basket Clinical Trial

American Journal of Hematology, Volume 101, Issue 2, Page 242-254, February 2026.
ABSTRACT Iptacopan is a first‐in‐class, oral, selective inhibitor of complement factor B that has demonstrated positive efficacy across several complement‐driven diseases. Here we evaluate the efficacy and safety of iptacopan monotherapy in adult patients with primary immune thrombocytopenia (ITP) and primary cold agglutinin disease (CAD). We performed
Alexander Röth, Wilma Barcellini, Christine Ademokun, Junho Jang, Maria Luisa Lozano, David Valcarcel Ferreiras, Cristina Pascual‐Izquierdo, Shripad Chitnis, Sofiya Matviykiv, Alessandra Vitaliti, Chi Chen, Vasiliki Katsanou, Raghav Chawla, Hanny Al‐Samkari   +13 more
wiley   +1 more source