Clearance of desialylated mouse alpha-macroglobulin and murinoglobulin in the mouse.
Mouse alpha-macroglobulin and murinoglobulin were labeled with 125I and utilized for plasma clearance studies performed with mice. Desialylated murinoglobulin was rapidly cleared from the circulation with a half-life of about 5 min. On the other hand, desialylated alpha-macroglobulin showed a biphasic curve: about half was cleared at a rate similar to that of the intact molecule while the remaining half had a shorter half-life of about 20 min which was prolonged by a simultaneous injection of a 200-fold excess of unlabeled asialoorosomucoid. Virtually no cross competition was observed between these asialoglobulins and formaldehyde-treated bovine serum albumin or trypsin-bound alpha-macroglobulin. These results suggest that the intravascular elimination of desialylated alpha-macroglobulin and murinoglobulin is independent of the clearance systems responsible for formaldehyde-modified proteins or proteinase-bound alpha-macroglobulins, and that the structure or spatial arrangement, or both, of oligosaccharide units of alpha-macroglobulin is somewhat different from that of murinoglobulin, resulting in a difference of avidity of interaction with the asialoglycoprotein receptor. The desialylated alpha-macroglobulin and murinoglobulin accumulated principally in the liver.
Abe
K
K
Department of Biochemistry, Kinki University School of Medicine, Osaka.
Yamamoto
K
K
Sinohara
H
H
D000818:Animals; D037263:Asialoglycoprotein Receptor; D001667:Binding, Competitive; D010450:Endopeptidases / Q000494:pharmacology; D005557:Formaldehyde / Q000493:pharmacokinetics; D006358:Hot Temperature; D008024:Ligands; D008297:Male; D008657:Metabolic Clearance Rate; D051379:Mice; D011971:Receptors, Immunologic / Q000378:metabolism; D012712:Serum Globulins / Q000378:metabolism*; D000511:alpha-Macroglobulins / Q000378:metabolism*
D037263:Asialoglycoprotein Receptor; D008024:Ligands; D011971:Receptors, Immunologic; D012712:Serum Globulins; D000511:alpha-Macroglobulins; C044177:murinoglobulin; D005557:Formaldehyde; D010450:Endopeptidases