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Two populations of complement factor H differ in their ability to bind to cell surfaces.

ABSTRACT: Using hydrophobic affinity chromatography on phenyl-Sepharose, human complement factor H can be separated into two subpopulations, phi 1 and phi 2. Although phi 1 and phi 2 are known to differ in their aggregation properties under non-physiological low ionic strength conditions, no difference in aggregation state was detected under the conditions used for cell-binding experiments. We have investigated these two subpopulations further to determine whether functional differences exist between them. The subpopulation phi 2 was found to bind specifically and saturably to the surface of Raji cells. The binding of the other subpopulation, phi 1, was low, and essentially non-specific. A monoclonal anti-factor H antibody, BGH-1, was raised which recognizes preferentially the phi 2 subpopulation and inhibits the binding of factor H to cell surfaces.

SUBMITTER: Ripoche J

PROVIDER: S-EPMC1149322 | biostudies-other | 1988 Jul

REPOSITORIES: biostudies-other

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Two distinct conformations of factor H regulate discrete complement-binding functions in the fluid phase and at cell surfaces.

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