Comparative growth of bovine lymphosarcoma cells and lymphoid cells infected with Theileria parva in athymic (nude) mice

MDM2 regulates a novel form of incomplete neoplastic transformation of Theileria parva infected lymphocytes

“…Among several Theileria species, T. parva is highly pathogenic for cattle and cause fatal lymphoproliferative diseases known as East Coast fever (Brown et al, 1973;Irvin et al, 1975;Lawrence and 1987). The MDM2 protein acts as a negative regulator of p53 through two known mechanisms: First, MDM2 binds p53 through its NH2-terminus, resulting in inhibition of its transcriptional activity (Momand et al, 1992), and second, the COOH-terminus of MDM2 serves as an E3 ubiquitin ligase targeting p53 for proteasomal degradation (Haupt et al, 1997).…”

Constitutive exclusion of Csk from Hck-positive membrane microdomains permits Src kinase-dependent proliferation ofTheileria-transformed B lymphocytes

“…Hallmarks of transformation are the capacity of infected cells to proliferate in vitro in the absence of exogenous growth factors or antigenic stimulation. 1 Moreover, Theileria-infected leukocytes behave as invasive tumors in both scid 2 and in athymic, irradiated mice, 3,4 and they can form colonies in soft agar. Parasite-dependent regulation of host cell signal transduction pathways is thought to be critical in establishing the transformed phenotype of infected leukocytes.…”

Jun NH2-terminal kinase is constitutively activated in T cells transformed by the intracellular parasiteTheileria parva

“…T. parva-infected cells show several characteristics of tumor cells. They can be cultured indefinitely in vitro and, most notably, they form invasive tumors when injected into nude mice (8). Transformation induced by T. parva is completely reversible, and lymphocytes return to a resting phenotype upon elimination of the parasite by treatment with the parasite-specific drug BW720c (6,9).…”