Hemolytic anemia is a major feature of paroxysmal nocturnal hemoglobinuria (PNH). Intravascular red blood cell (RBC) destruction is caused by increased sensitivity of the abnormal erythrocyte to complement-mediated lysis, due to the GPI absence of a membrane-bound glycosylphosphatidylinositol (GPI)-linked protein, which functions as an inhibitor of reactive lysis (CD59). Both in vivo and in vit...

It has been hypothesized that complement inhibitors expressed on the surface of tumor cells prevent effective immune-mediated clearance. Whereas there are in vitro data to support this hypothesis, the speciesselective activity of complement inhibitors has been a hindrance to investigating the role of membrane-bound complement inhibitors in rodent models of human cancer. The CD59-positive LAN-1 ...

It has been recently hypothesized that the CD59 gene has two putative p53-responsive elements that may be involved in defense of host cells from damage by the complement system in inflammation. Here we have examined the roles of these putative p53-binding sequences within the CD59 gene in regulation of CD59 expression. We have shown that both of these potential responsive elements bind p53 in v...

CD59 antigen (CD59) is a glycosylphosphatidylinositol (GPI)-linked membrane glycoprotein which protects human cells from complement-mediated lysis. Here we report the expression of functionally active CD59 in Spodoptera frugiperda insect cells using a baculovirus vector. Recombinant CD59 was expressed abundantly on the surface of the insect cells and protected the cells from lysis by human comp...

Biotinylation of erythrocytes (E) followed by avidin cross-linking at specific sites has been suggested as a novel means of drug delivery. Upon avidin cross-linking, biotinylated E become complement-activating and highly susceptible to complement lysis, thus bringing about release of entrapped drug. We set out to examine the mechanisms of this biotin-avidin-induced lytic susceptibility, focusin...

GPI-anchored surface proteins mediate many important functions, including transport, signal transduction, adhesion, and protection against complement. They cluster into glycolipid-based membrane domains and caveolae, plasmalemmal vesicles involved in the transcytosis and endocytosis of these surface proteins. However, in lymphocytes, neither the characteristic flask shaped caveolae nor caveolin...

Abstract The opportunistic pathogen Pseudomonas aeruginosa has gained precedence over the years due to its ability develop resistance existing antibiotics, thereby necessitating alternative strategies understand and combat bacterium. Our previous work identified interaction between bacterial lectin LecA host cell glycosphingolipid receptor globotriaosylceramide (Gb3) as a crucial step for engul...

CD55, CD59, CD46, and CD35 are proteins with complement regulatory (Creg) properties that ensure cell and tissue integrity when this system is activated. The aim of this study was to evaluate the Creg expression on peripheral blood cells from SLE patients and its association with cytopenia and disease activity. Flow cytometric analyses were performed on blood cells from 100 SLE patients and 61 ...

Paroxysmal nocturnal hemoglobinuria (PNH) results from somatic mutations in the PIG-A gene, leading to poor presentation of glycosylphosphatidylinositol (GPI)-anchored surface proteins. PNH frequently occurs in association with suppressed hematopoiesis, including frank aplastic anemia (AA). The relationship between GPI-anchored protein expression and bone marrow (BM) failure is unknown. To asse...

Paroxysmal nocturnal hemoglobinuria (PNH) results from the expansion of a hematopoietic clone that is deficient in glycosylphosphatidylinositol-anchored molecules. PNH is characterized by chronic hemolysis with acute exacerbations due to the uncontrolled activity of complement on PNH cells, which lack the inhibitor of homologous complement, CD59. Symptoms include severe fatigue, hemoglobinuria,...