Secretory IgAs from human milk with affinity to mammalian DNA are capable of hydrolyzing ribosomal RNA

Ukr Biokhim Zh (1999). 2007 May-Jun;79(3):55-60.

Abstract

It was found that milk of clinical healthy women contains sIgA possessing high affinity for the mammalian thymus DNA and DNA-hydrolyzing activity (sIgA-abzymes). Here we present data that such sIgA-abzymes, purified by sequential chromatography on DEAE-fractogel, heparin-sepharose, DNA-cellulose and followed by gel-filtration, are also able to hydrolyse total RNA from E. coli better than plasmid DNA. Besides, such sIgA-abzymes effectively cleaved 18S and 28S ribosomal RNA isolated from human A549 cells. It is noteworthy that the nuclease activity of sIgA-abzymes was significantly inhibited by ATP, while dATP had no effect on it. A potential role of the ribonuclease activity of sIgA-abzymes present in human milk is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Antibodies, Catalytic / isolation & purification
  • Antibodies, Catalytic / pharmacology*
  • Antibody Affinity
  • Catalysis
  • Cattle
  • Chromatography, Ion Exchange
  • DNA / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Endonucleases / isolation & purification
  • Endonucleases / pharmacology*
  • Escherichia coli / metabolism
  • Female
  • Humans
  • Hydrolysis
  • Immunoglobulin A, Secretory / isolation & purification
  • Immunoglobulin A, Secretory / pharmacology*
  • Milk, Human / chemistry*
  • Milk, Human / immunology
  • RNA, Bacterial / metabolism*
  • RNA, Ribosomal / metabolism*

Substances

  • Antibodies, Catalytic
  • Immunoglobulin A, Secretory
  • RNA, Bacterial
  • RNA, Ribosomal
  • Adenosine Triphosphate
  • DNA
  • calf thymus DNA
  • Endonucleases