Hamster female protein. A new Pentraxin structurally and functionally similar to C-reactive protein and amyloid P component.

Abstract

Female protein (FP), a serum protein present in normal female hamsters was found to be similar to acute-phase reactant, C-reactive protein (CRP) and serum amyloid P component (SAP) in the following ways: (a) hamster FP complexed with phosphorylcholine (PC) in a Ca++-dependent fashion as shown by its isolation from serum by affinity chromatography with PC-Sepharose and selective elution with free PC or EDTA; (b) electron microscopy of FP indicated a pentameric structure similar in size and appearance to other pentraxins; (c) the parent molecule of FP (150,000 mol wt) was composed of five noncovalantly assembled subunits of 30,000 mol wt; and (d) the amino acid analysis and terminal NH2 sequence of FP clearly showed homology with SAP-CRP. Although FP evolved from an ancestral gene common to SAP and CRP, and shares functional, morphological and structural properties with these acute-phase proteins, the biological homology of FP appears quite diverse as this protein is a prominent serum constituent (1-2 mg/ml) of normal female hamsters and under hormonal control (testosterone suppression) in males.

Comparative analyses of pentraxins: implications for protomer assembly and ligand binding

“…On the other hand, human SAP specifically binds to the 4,6 cyclic pyruvate acetal of [3-D-galactose (MO3DG) [16] and also to all types of amyloid fibrils [17], which are not recognized by human CRP. The major pentraxin in Syrian hamsters, formerly known as female protein [18] (here designated HSAP), is the hamster counterpart of human SAP, in that it binds to hamster amyloid [19,20], but it shares with human CRP the capacity to bind to PC as well as PE [18,21].…”

Definition of cotton rat immunoglobulins: sigmodon species differ in expression of IgG isotypes and production of respiratory syncytial virus antibody

“…Anti-IgG2 was made specific by addition of anodally migrating IgG1 that was separated from IgG2 by pevikon block electrophoresis, or by addition of IgG1 anti-hen egg albumin (HEA) that was isolated by HEA affinity chromatography. 12 Anti-IgG1 was made by inoculating rabbits with IgG1 purified by protein A chromatography, or by HEA affinity chromatography; for the latter, HEAimmunized SH sera containing only IgG1 anti-HEA was passed through a Sepharose column conjugated to HEA by cyanogen bromide. The rabbit antisera were specific after absorption with electrophoretically slow migrating IgG(IgG2) isolated by pevikon block electrophoresis.…”

“…11,12 IgG1 and IgG2 were purified and concentration determined by Kjeldahl and UV absorption ( P 1% 280 =14 . 4).…”

“…Cotton rat serum was fractionated by G200 Sephadex (Pharmacia, Uppsala, Sweden) or on a 10-40% sucrose density gradient using HEA and diethylaminoethyl (DEAE)-purified rabbit gamma globulin (RGG) as 4S and 7S markers as previously described. 12 HEA haemagglutination was performed with sheep red blood cells that were coupled to HEA via bis-diazotized benzidine. 17 Simple gel diffusion in agarose was used to test for antigenic identity of IgG isotypes within various cotton rat species.…”

“…[11][12][13] Anti-IgG2 was made in rabbits by inoculation of the most cathodal IgG found after pevikon block electrophoresis of SF and SH serum. Anti-IgG2 was made specific by addition of anodally migrating IgG1 that was separated from IgG2 by pevikon block electrophoresis, or by addition of IgG1 anti-hen egg albumin (HEA) that was isolated by HEA affinity chromatography.…”