Insulin-like growth factors stimulate growth and L-cysteine uptake by the intestinal parasite Giardia lamblia

Hugo D. Luján, Michael R. Mowatt, Lee J. Helman, Theodore E. Nash

Research output: Contribution to journalArticle

Abstract

Giardia lamblia, a parasitic protozoan responsible for diarrhea and malabsorption in humans, grows axenically only in media that contain serum and a high concentration of L-cysteine. During our attempts to grow Giardia in the absence of serum, we found that: (a) human insulin-like growth factors (especially IGF-II), but not insulin, promote the growth and L-cysteine uptake by G. lamblia trophozoites; (b) the growth stimulation was inhibited by αIR3, an anti-type 1 IGF receptor monoclonal antibody, but an anti-type 2 IGF receptor antibody had no effect; and (c) IGFs act on Giardia through a type 1 IGF receptor-like protein, which can bind IGF-II with higher affinity than IGF-I, and most likely possesses intrinsic phosphotyrosine kinase activity.

Original languageEnglish (US)
Pages (from-to)13069-13072
Number of pages4
JournalJournal of Biological Chemistry
Volume269
Issue number18
StatePublished - May 6 1994

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Insulin-like growth factors stimulate growth and L-cysteine uptake by the intestinal parasite Giardia lamblia'. Together they form a unique fingerprint.

  • Cite this