Isolation, characterization, and cloning of porcine complement component C7.
نویسندگان
چکیده
Activation of the complement system through the classical, alternative, or lectin pathway results in the formation of the terminal complement complex. C7 plays an integral role in the assembly of this complex with target cell membranes. To date, only human C7 has been cloned and characterized; thus, in this study, we characterized the porcine complement component C7. Porcine C7 was isolated by affinity chromatography as a single glycoprotein with an approximate molecular mass of 90 kDa and 100 kDa under reducing and nonreducing conditions, respectively. The full-length porcine C7 cDNA was isolated, and the predicted amino acid sequence exhibited 80% identity with human C7 with conservation of the cysteine backbone and two putative N-linked glycosylation sites. Porcine C7 mRNA expression was detected in all tissues investigated, except polymorphonuclear and mononuclear leukocytes. Addition of purified porcine C7 restored the hemolytic activity of C7-depleted human sera in a dose-dependent manner. A functionally inhibitory mAb against porcine C7 attenuated the hemolytic activity of human, rabbit, or rat sera, suggesting an important conserved C7 epitope among species. These data demonstrate that porcine and human C7 are highly conserved, sharing structural and functional characteristics.
منابع مشابه
Isolation, cloning and functional characterization of porcine mannose-binding lectin.
Binding of mannose-binding lectin (MBL), a C-type lectin, and its associated serine proteases, MASP-1 and MASP-2, to cell surface carbohydrates activates the lectin complement pathway. As MBL plays an important role in innate immunity, it has been cloned and characterized in several species. While the pig may be used as a source of organs/tissues for xenotransplantation, little is known about i...
متن کاملMolecular Cloning, Characterization, and Expression of Cuc m 2, a Major Allergen in Cucumis melo
Background: Several studies reported the clinical features of IgE-mediated hypersensitivity after ingestion of melon. Melon allergy is a common IgE-mediated fruit allergy in Iran. This prompted us to investigate immunochemical and molecular properties of the major allergen in melon fruit, to compare the IgE-binding capacity of the natural protein with the recombinant allergen, and to determine ...
متن کاملComplete primary structure and functional characterization of the sixth component of the human complement system. Identification of the C5b-binding domain in complement C6.
Complement C6 is one of five plasma proteins that are incorporated into the lytic terminal complement complex on lipid membranes (C5b-9m) upon activation of the complement cascade. Oligonucleotide probes derived from partial amino acid sequences of purified C6 were used to isolate cDNA clones from a human liver cDNA library. The complete polypeptide structure of mature C6 deduced from the cDNA ...
متن کاملThe three-way relationship of polymorphisms of porcine genes encoding terminal complement components, their differential expression, and health-related phenotypes
BACKGROUND The complement system is an evolutionary ancient mechanism that plays an essential role in innate immunity and contributes to the acquired immune response. Three modes of activation, known as classical, alternative and lectin pathway, lead to the initiation of a common terminal lytic pathway. The terminal complement components (TCCs: C6, C7, C8A, C8B, and C9) are encoded by the genes...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of immunology
دوره 165 2 شماره
صفحات -
تاریخ انتشار 2000