Mannan-binding lectin (MBL)-associated plasma protein present in human urine inhibits calcium oxalate crystal growth

FEBS Lett. 1999 Nov 26;462(1-2):89-93. doi: 10.1016/s0014-5793(99)01509-4.


Mannan-binding lectin (MBL)-associated plasma protein (MAp19) is an alternatively spliced form of MBL-associated serine protease-2, a component of a complement activation cascade. We observed that MAp19 is excreted in human urine. Interestingly, the amount of MAp19 was higher in urine of renal cell carcinoma patients than healthy people. Pretreatment of urine dialysate with 50 mM EDTA increased the recovery of MAp19, suggesting that MAp19 is a calcium-binding protein. The recombinant MAp19 showed a strong inhibition of calcium oxalate crystal growth in vitro in a concentration-dependent manner. Thus, we conclude that MAp19 plays a role in the inhibition of calcium oxalate renal stone formation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alternative Splicing
  • Amino Acid Sequence
  • Blood Proteins / chemistry
  • Blood Proteins / isolation & purification
  • Blood Proteins / urine*
  • Calcium Oxalate / chemistry*
  • Calcium-Binding Proteins / metabolism
  • Calcium-Binding Proteins / urine
  • Crystallization
  • Humans
  • Lectins*
  • Mannans*
  • Mannose-Binding Protein-Associated Serine Proteases
  • Molecular Sequence Data
  • Recombinant Proteins / chemistry
  • Sequence Analysis
  • Serine Endopeptidases / chemistry
  • Serine Endopeptidases / urine*


  • Blood Proteins
  • Calcium-Binding Proteins
  • Lectins
  • Mannans
  • Recombinant Proteins
  • Calcium Oxalate
  • MASP2 protein, human
  • Mannose-Binding Protein-Associated Serine Proteases
  • Serine Endopeptidases