title: Homozygous FVII deficiencies with different reactivity towards tissue thromboplastins of different origin.
abstract: The reagents most frequently used for FVII activity assay are obtained by rabbit brain or human placenta. In recent years, human recombinant thromboplastins have received great attention. FVII activity in FVII deficiency is usually low, regardless of the thromboplastin used. There are  a few exceptions to this rule. These are represented by FVII Padua (Arg304Gln), FVII Nagoya (Arg304Trp), and FVII (Arg79Gln). In these three instances, clear discrepancies were noted in the FVII activity depending on the thromboplastin used. This indicates that at least two areas of FVII are  involved in tissue binding, namely an epidermal growth factor domain of the light chain (Arg79Gln) and the catalytic domain (Arg304), controlled by exons 4 and 8, respectively. Since these three variants are cross reactive material positive, namely they are Type 2 defects, all other variants  with normal antigen should be investigated by a panel of at least three tissue thromboplastins (rabbit brain, human tissue or human recombinant, and ox brain derived) in order to obtain a satisfactory classification.
authors.affiliation: Department of Medical and Surgical Sciences and Northeastern Italy Association for the Study of Coagulation Disorders, University of Padua Medical School, Padua, Italy. antonio.girolami@unipd.it
authors.forename: A
authors.initials: A
authors.lastname: Girolami
authors.forename: P
authors.initials: P
authors.lastname: Scarparo
authors.forename: E
authors.initials: E
authors.lastname: Bonamigo
authors.forename: M
authors.initials: M
authors.lastname: Treleani
authors.forename: A M
authors.initials: AM
authors.lastname: Lombardi
mesh_terms: D000818:Animals; D005167:Factor VII / Q000235:genetics* / Q000378:metabolism; D005168:Factor VII Deficiency / Q000188:drug therapy* / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D011817:Rabbits; D013925:Thromboplastin / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D005167:Factor VII; D013925:Thromboplastin