Article thumbnail
Location of Repository

Transforming Growth Factor α Binds to Trypanosoma cruzi Amastigotes To Induce Signaling and Cellular Proliferation

By A. Deloris Alexander, Fernando Villalta and Maria F. Lima


Macrophages secrete transforming growth factor α (TGF-α) to trigger proliferation of cancer cells. Here, we report a new role for TGF-α in modulating the direct cellular proliferation of a parasitic protozoan, Trypanosoma cruzi. Amastigotes present two classes of receptors for TGF-α with different binding affinities. (125)I-TGF-α binding was competed by an excess of cold epidermal growth factor and TGF-α but not by an irrelevant molecule. Upon binding of TGF-α to amastigotes, the ligand is internalized, inducing trypanosome tyrosine phosphorylation of 90- and 87-kDa proteins and increasing DNA synthesis and proliferation of amastigotes. Furthermore, exposure of macrophages to TGF-α induced increased amastigote proliferation. These results describe a novel mechanism used by amastigotes to regulate their proliferation mediated by a TGF-α-dependent signal transduction pathway

Topics: Fungal and Parasitic Infections
Publisher: American Society for Microbiology
Year: 2003
DOI identifier: 10.1128/IAI.71.7.4201-4205.2003
OAI identifier:
Provided by: PubMed Central
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.