Search results for "Complement System"
showing 7 items of 157 documents
Host defence mechanisms against bacterial aggression in periodontal disease : basic mechanisms
2009
Periodontal diseases are complex bacteria-induced infections characterised by an inflammatory host response to plaque microbiota and their by-products. Most of these microorganisms have virulence factors capable of causing massive tissue destruction both directly, through tissue invasion and the production of harmful substances, or indirectly, by activation of host defense mechanisms, creating an inflammatory infiltrate of potent catabolic activity that can interfere with normal host defense mechanisms. In response to the aggression, host defense mechanisms activate innate and adaptive immune responses. Our aim is to offer a general overview of the main mechanisms involved in the host respo…
Combined homozygous factor H and heterozygous C2 deficiency in an Italian family
1988
Three of four children in a family have homozygous (less than 1% of normal) deficiency of factor H of the complement system and both parents, who are first cousins, are heterozygous for the same defect. The father and two of the H-deficient siblings also have a partial C2 deficiency. One of the children with combined deficiencies is affected by systemic lupus erythematosus with nephritis. No increased susceptibility to infections has been observed in the family. H deficiency is inherited in an autosomal codominant manner and is independently transmitted from C2 deficiency and HLA haplotypes. In the homozygous state it is associated with very low serum concentrations of B and C3, barely demo…
The efficacy of two immunostimulants against Flavobacterium columnare infection in juvenile rainbow trout (Oncorhynchus mykiss).
2009
Abstract Bacterium Flavobacterium columnare is the causative agent of columnaris disease in many wild and farmed fish species. Immunostimulants are used with success in aquaculture against many pathogens, but the ability to improve innate resistance to columnaris disease has not been studied. Fingerling rainbow trout were treated with two immunostimulants, yeast β-glucan and β-hydroxy-β-methylbutyrate (HMB). Selected innate immune function parameters, the production of reactive oxygen species (ROS) by whole blood and by isolated head kidney leukocytes, plasma lysozyme activity and complement bacteriolytic activity, were determined to assess the immune status of fish. The fish were then bath…
hDAF expression in hearts of transgenic pigs obtained by sperm-mediated gene transfer.
2000
TRANSPLANTATON has been the choice option to treat successfully an increasing number of acute and chronic human pathologies with declining morbidity and mortality. However, availability of organs from human donors is limited and dramatically inadequate with respect to patient requests. Xenotransplantation from large-sized mammals has thus been reconsidered as a tool to overcome the present unbalance between organ offers and requests. Pigs have been chosen because they can be easily and cheaply bred; they do not raise ethical questions—their use as alimentary resources is generally admitted; and they possess organs largely human compatible for size, anatomical organization, and physiology. N…
Proteomic Profiling of Secreted Proteins for the Hematopoietic Support of Interleukin-Stimulated Human Umbilical Vein Endothelial Cells
2013
Human umbilical cord vein endothelial cells (HUVECs) secrete a number of factors that greatly impact the proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs). These factors remain largely unknown. Here, we report on the most comprehensive proteomic profiling of the HUVEC secretome and identified 827 different secreted proteins. Two hundred and thirty-one proteins were found in all conditions, whereas 369 proteins were identified only under proinflammatory conditions following IL-1β, IL-3, and IL-6 stimulation. Thirteen proteins including complement factor b (CFb) were identified only under IL-1β and IL-3 conditions and may potentially represent HSPC prolifer…
Digestive vacuoles of Plasmodium falciparum are selectively phagocytosed by and impair killing function of polymorphonuclear leukocytes.
2011
AbstractSequestration of parasitized erythrocytes and dysregulation of the coagulation and complement system are hallmarks of severe Plasmodium falciparum malaria. A link between these events emerged through the discovery that the parasite digestive vacuole (DV), which is released together with infective merozoites into the bloodstream, dually activates the intrinsic clotting and alternative complement pathway. Complement attack occurs exclusively on the membrane of the DVs, and the question followed whether DVs might be marked for uptake by polymorphonuclear granulocytes (PMNs). We report that DVs are indeed rapidly phagocytosed by PMNs after schizont rupture in active human serum. Uptake …