Protein‐bound polyamines in the plasma of mice grafted with the Lewis lung carcinoma

Abstract

Protein-bound polyamines were isolated from the plasma of mice using antipolyamine antibodies covalently linked to magnetic latex spheres. Their subsequent separation by polyacrylamide gel electrophoresis (PAGE) showed that in plasma from normal mice, 3 proteins (27, 55 and 82 kDa) carrying polyamines could be visualized, whereas in mice bearing the Lewis lung carcinoma at least 8 other proteins of higher molecular mass (5 of 94,110,130,145 and 160 kDa, and 3 of > 170 kDa) had bound polyamines. These protein-bound polyamines could be detected from the first week after tumour graft; they increased during the second and third week but decreased thereafter. These proteins were not bound by immunolatex spheres preincubated with spermine bound to a protein-carrier insulin. Moreover, the appearance of these protein-bound polyamines was not a consequence of the inflammatory process since in mice infected with heat-inactivated Brucella abortus, with the exception of a 65 kDa protein, polyamines were bound to the same proteins found in normal mice. In mice grafted with the Lewis lung carcinoma the concomitant decrease in transglutaminase-mediated polyamine (e.g. putrescine) binding capacity of plasma proteins provides additional evidence for the presence in vivo of polyamines already bound to plasma proteins.

Immunization of Rabbits with Spermine Induces Antibodies to Self Antigens

“…In this cationizcd state, it can interact with molecules as diverse as dsDNA [24], plasma peptides [19,25], or proteins [20,24] such as fibronectin [26], Poly amines may also be covalently bound to proteins under the action of transglutaminases found in the circulation (fac tor XIII) or in cells [reviewed in refs. 27,28] and such in teractions could increase the immunogenicity of the mod ified molecules.…”

“…[14C]-Polyamines, administered intra venously to human patients or to animals, become rapidly conjugated [17,18], and polyamines complexed to peptides [19] or to proteins [20] have been found in plasma.…”

Post-translational modification of apolipoprotein B by transglutaminases

“…a2-macroglobulin and fibronectin (Mosher, 1976), OC2-plasmin inhibitor (Sakata & Aoki, 1980;Carmassi & Chung, 1983), Factor V (Francis et al, 1986), von Willebrand factor (Hada et al, 1986) and thrombospondin (Bale & Mosher, 1986). The reports that plasma factor XIIIa activity is significantly higher in hypertriglyceridaemic patients than in normolipaemic controls (Cucuianu et al, 1973(Cucuianu et al, , 1976, and that polyamines may be covalently incorporated into lipoproteins (Delcros et al, 1987) (Hatch & Lees, 1968) isolated at density 1.006 g/ml (16 h), IDL at densities between 1.006 and 1.019 g/ml (20 h) and LDL at densities between 1.019 and 1.063 g/ml (20 h). The respective lipoproteins were washed after the initial centrifugation by refloating them at a higher solvent density.…”