Results 61 to 70 of about 2,111 (96)

Cyanate as an Inactivator of Complement Proteins

Journal of Immunology, 1975
Abstract Sodium cyanate added to normal human serum or serum from patients with sickle-cell disease resulted in the functional inactivation of C3, C5, C6, C7, and the C3b inactivator, but not C8 and C9. Final concentrations as low as 0.5 mM in serum caused inactivation of 12 to 64% of the C3 after 8 hr at 37°C.
D R, Schultz, P I, Arnold
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Complement inactivating proteins and intraspecies venom variation in Crotalus oreganus helleri

Toxicon, 2007
Complement inactivating properties were detected in venom from the southern California distribution of Crotalus oreganus helleri (Southern Pacific Rattlesnake). This activity showed strong geographic bias to the San Bernardino Mountain range, and venom from this area reacted strongly with Fraction 5 antiserum (AF5). However, venoms from the San Jacinto
William K. Hayes, Jennifer D. Jurado, Jeremy A. Ross, Sean P. Bush, Ernesto S. Nakayasu, Carl S. Lieb, Eppie D. Rael   +6 more
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Antibody-complement-mediated cytotoxicity is enhanced by ribosome-inactivating proteins.

The Journal of Immunology, 1985
Abstract The antibody-mediated cytotoxicity of complement can be increased by the ribosome-inactivating proteins gelonin and PAP-S. Treatment of human lymphoid cells that express CALLA with an anti-CALLA monoclonal antibody, J5, and then with rabbit complement, leaves about 6% of the cells alive.
V S, Goldmacher, J, Anderson, W A, Blättler, J M, Lambert, P D, Senter   +4 more
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Interaction of vaccinia virus complement control protein with human complement proteins: Factor I-mediated degradation of C3b to iC3b1 inactivates the alternative complement pathway

Molecular Immunology, 1998
Abstract Vaccinia virus complement control protein (VCP) is a virulence determinant of vaccinia virus that helps protect the virus from the complement attack of the host. To characterize the interaction of VCP with C3 and C4 and understand the mechanism by which VCP inactivates complement, we have expressed VCP in a yeast expression ...
Stuart N. Isaacs, Arvind Sahu, Athena M. Soulika, John D. Lambris   +3 more
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Preferential inactivation of the C5 convertase of the alternative complement pathway by factor I and membrane cofactor protein (MCP)

Molecular Immunology, 1991
Human C3b bound to the ghost of sheep erythrocytes (E*) via activation of the alternative complement pathway (E*AC3b) consists of four major constituents on SDS-PAGE of 350, 260, 210 and 180 kDa. 350 kDa C3b is a dimeric form of C3b in which the alpha' chain of one C3b binds covalently to that of the other C3b.
Hong Kyongsu, John P. Atkinson, Kinoshita Taroh, Okada Michiyo, Matsumoto Misako, Seya Tsukasa   +5 more
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Molecular Interactions of the Control Proteins C3b Inactivator and β1H with Various Complement Intermediates

The Journal of Immunology, 1978
Abstract Radioiodinated β1H was demonstrated to bind to sheep EAC4b, EAC4,2,3b and EC3b, but not to E, EA, EAC4,2 or to C3bINA and β1H treated EC3b. This binding was dependent upon the C3b concentration on the surface of the cells and could be inhibited by unlabeled β1H, free C3b or high concentrations of Factor B.
M. K. Pangburn, R. D. Schreiber, H. J. Müller-Eberhard   +2 more
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Limited Proteolysis of Complement Protein C3b by Regulatory Enzyme C3b Inactivator: Isolation and Characterization of a Biologically Active Fragment, C3d,g

The Journal of Biochemistry, 1985
Limited proteolysis of C3b by C3b inactivator (factor I) consists of a two-step reaction; rapid cleavage of C3b to yield a nicked C3b derivative, iC3b, and followed by slow cleavage of iC3b to yield two antigenically distinct fragments, C3c and C3d,g.
Tsukasa Seya, Shigeharu Nagasawa
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Factor I-Dependent Inactivation of Human Complement C4b of the Classical Pathway by C3b/C4b Receptor (CR1, CD35) and Membrane Cofactor Protein (MCP, CD46)1

The Journal of Biochemistry, 1992
Proteolytic inactivation of C4b is a crucial step for regulation of the classical complement pathway. A plasma protease factor I and membrane cofactors, C3b/C4b receptor (CR1) and membrane cofactor protein (MCP), participate in the regulation of cell-bound C4b although the physiological potency of these cofactors remains unknown.
Misako Matsumoto, Takahisa Masaki, Isao Nakanishi, Reiko Yasuda, Tsukasa Seya   +4 more
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Regulatory proteins for the activated third and fourth components of complement (C3b and C4b) in mice. I. Isolation and characterization of factor H: the serum cofactor for the C3b/C4b inactivator (Factor I)

Journal of Immunological Methods, 1984
Factor H, purified from mouse EDTA-plasma using a 4-step procedure, consists of a single polypeptide chain of Mr 150,000 on SDS-PAGE. Mouse H (Hmo) was required for the cleavage of fluid-phase mouse C3b by mouse I (Imo). The final product of degradation of fluid-phase mouse C3b was iC3b, consisting of fragments of the alpha'-chain (alpha'-70, alpha'-43)
Taroh Kinoshita, Victor Nussenzweig
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The fourth component of human complement treated with amines or chaotropes or frozen-thawed (C4b-like C4): interaction with C4 binding protein and cleavage by C3b/C4b inactivator.

The Journal of Immunology, 1982
Abstract We have shown previously that C4 treated with amines or chaotropes, although uncleaved, exhibits properties that are similar to C4b. Studies by other groups suggest that this C4b-like form of C4 is characterized by the lack of an internal thiolester bond that is present in native C4.
I, von Zabern, E L, Bloom, V, Chu, I, Gigli   +3 more
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