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A-431 cells and human keratinocytes synthesize and secrete the third component of complement

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      Abstract

      Biosynthetic radiolabeling studies demonstrate that A-431 cells, a human epidermoid carcinoma cell line, and human keratinocytes synthesize and secrete C3 as two disulfidelinked polypeptide chains of 120 and 75 kD. Moreover, epithelial cell-derived C3 co-migrates in SDS-PAGE with that produced by HepG2 cells, a human hepatoma cell line previously used to elucidate complement component biosynthesis. Pulse-chase studies in A-431 cells demonstrate that epithelial cell-derived C3 is produced as a 195-kD precursor molecule, pro-C3, which is processed intracellularly by limited proteolysis into 120- and 75-kD C3 alpha and beta chains. Comparative studies demonstrate that A-431 cellderived C3 is synthesized, processed, and secreted in parallel but in lower quantity than that produced by HepG2 cells. Treatment of biosynthetically labeled A-431 cell culture supernatants with normal human serum and zymosan produces C3 alpha chain cleavage and specific C3 fragments that are not present in control culture supernatants treated with heatinactivated human serum and zymosan. Northern blot analysis of total cellular RNA extracted from A-431 cells, human keratinocytes, and HepG2 cells reveals qualitative identity of a 5.1-kb C3 mRNA species in these three cell types. Epithelial cell-derived C3 may play an important role in local inflammatory and immunologic reactions including such reactions in human skin. Moreover, epithelial cell C3 synthesis may have direct relevance to the recent demonstration of C3d,g within selected normal primate epithelial basement membranes, including epidermal basement membrane.

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      References

        • Brown E
        • Joiner K
        • Frank MM
        Complement.
        in: Paul WE Fundamental Immunology. Raven Press, New York1984: 645-668
        • Tack B
        • Harrison R
        • Janatova J
        • Thomas M
        • Prahl J
        Evidence for presence of an internal thiolester bond in third component of human complement.
        in: 2nd ed. Proc Natl Acad Sci USA. 77. 1980: 5764-5768
        • Fries L
        • Frank MM
        Molecular mechanisms of complement action.
        in: Stamatoyannopoulous G Neinhuis A Leder P Majerus P The Molecular Basis of Blood Diseases. W.B. Saunders, St. Louis1987: 450-498
        • Basset-Séguin N
        • Dersookian M
        • Cehrs K
        • Yancey KB
        C3d,g is present in normal human epidermal basement membrane.
        J Immunol. 1988; 141: 1273-1280
        • Leivo I
        • Engvall E
        C3d fragment of complement interacts with laminin and binds to basement membranes of glomerulus and trophoblast.
        J Cell Biol. 1986; 103: 1091-1100
        • Basset-Séguin N
        • Uhle P
        • Emanuel D
        • Henry P
        • Yancey KB
        Defective expression of basement membrane-associated C3d,g in papulonodular basal cell carcinomas.
        J Invest Dermatol. 1989; 92: 734-738
        • Morris K
        • Goldberger G
        • Colten H
        • Aden D
        • Knowles B
        Biosynthesis and processing of a human precursor complement protein, pro-C3, in a hepatoma-derived cell line.
        Science. 1982; 215: 399-400
        • Basset N
        • Vie A
        • Blanchard J
        • Guilhou JJ
        Expression of c-Myc, c-Myb, c-Erb-G, and c-H-Ras oncogene mRNAs in fibroblasts cultured from psoriatic patients.
        Dermatologica. 1987; 175: 296-299
        • Stanley J
        • Hawley-Nelson P
        • Yuspa S
        • Shevach E
        • Katz SI
        Characterization of bullous pemphigoid antigen: a unique basement membrane protein of stratified squamous epithelia.
        Cell. 1981; 24: 897-903
        • Laemmli UK
        Cleavage of structural proteins during the assembly of the head of bacteriophage T4.
        Nature (Lond). 1970; 277: 680-685
        • Yancey KB
        • Hammer CH
        • Harvath L
        • Renfer L
        • Frank MM
        • Lawley TJ
        Studies of human C5a as a mediator of inflammation in normal human skin.
        J Clin Invest. 1985; 75: 486-495
        • Senger D
        • Hynes R
        C3 component of complement secreted by established cell lines.
        Cell. 1978; 15: 375-384
        • Sambrook J
        • Fritsch EF
        • Maniatis T
        Isolation of total RNA by extraction with strong denaturants.
        in: 2nd ed. Molecular Cloning, A Laboratory Manual. Cold Spring Harbor Laboratory Press, Cold Spring Harbor1989: 718-722
        • De Bruijun MHL
        • Fey G
        Human complement component C3: cDNA coding sequence and derived primary structure.
        in: Edition 3. Proc Natl Acad Sci USA. 82. 1985: 708-712
        • Strunk R
        • Whitehead A
        • Cole F
        Pretranslational regulation of the synthesis of the third component of complement in human mononuclear phagocytes by the lipid A portion of lipopolysaccharide.
        J Clin Invest. 1985; 76: 985-990
        • Katz SI
        The epidermal basement membrane zone-structure, ontogeny, and role in disease.
        J Am Acad Dermatol. 1984; 11: 1025-1037