Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because of the potential significance of external components of the obligate intracellular parasite Rickettsia rickettsii in host-parasite interactions, we have begun the first phase of a study to isolate and characterize surface antigens of this organism. An antiserum to a rickettsial surface component was obtained from rabbits inoculated with immune precipitates prepared by crossed immunoelectrophoresis of Triton X-100 extracts of R. rickettsii strain R. This antiserum (i) protected guinea pigs inoculated with 10,000 guinea pig 50% infectious doses of R. rickettsii against fever, (ii) prevented death of mice challenged with 2 50% lethal doses of R. rickettsii, and (iii) reacted in the microimmunofluorescence test with 9 of 13 spotted fever group serotypes tested. The location of this antigen on the rickettsial surface was demonstrated by immunoelectron microscopy with ferritin-labeled antibodies.
 ...
PMID:Biological properties of rabbit antibodies to a surface antigen of Rickettsia rickettsii. 640 67

Clinical and experimental evidence suggests an important role for oxidative stress and associated cellular defense mechanisms in the pathogenesis of vasculopathic rickettsioses. Our laboratory has reported that R. rickettsii infection of endothelial cells in vitro induces the expression of HO-1, the inducible isoform of the antioxidant defense enzyme heme oxygenase. HO-1 plays a critical role in maintaining the integrity of the vasculature and controls the functioning of the cyclooxygenase (COX) system. This study was undertaken to investigate the expression of COX and HO isozymes during in vitro infection of EC with two major representatives of spotted fever group Rickettsia species. The mRNA expression of COX-2 was significantly increased in endothelial cells infected with R. rickettsii and R. conorii, while that of COX-1 remained unaffected. Western blot analysis using total protein lysates from infected endothelial cells and corresponding uninfected controls further confirmed specific induction of COX-2 in response to infection. ELISA measurements on culture supernatants also suggested enhanced secretion of 6-keto PGF(1alpha) (stable hydrolysis product of PGI(2) and PGE(2). As a functional consequence of HO-1 upregulation, increased expression of the iron storage protein ferritin following R. rickettsii and R. conorii infection was also evident. Since products of HO-1 and COX-2 reactions govern a variety of physiologically important functions in the vasculature, further studies to define their regulation in the host cell should provide useful insights into the pathogenesis of rickettsial diseases.
 ...
PMID:Potential roles for regulatory oxygenases in rickettsial pathogenesis. 1648 16