Rapid thymomas induced by Abelson murine leukemia virus

Area of Science:

• Virology
• Immunology
• Oncology

Background:

• Abelson murine leukemia virus (A-MuLV), derived from Moloney leukemia virus, typically causes peripheral and bone marrow lymphomas.
• Conventional routes of A-MuLV injection do not typically result in thymomas or T cell tumors.

Purpose of the Study:

• To investigate if intrathymic injection of A-MuLV can induce thymomas.
• To characterize the resulting thymomas and their cellular origins.

Main Methods:

• Intrathymic injection of A-MuLV into BALB/c and C57BL/Ka mice.
• Establishment and cloning of tissue culture lines from induced thymomas.
• Characterization of cell surface markers (Thy-1, Lyt-1) and viral protein (p120).
• In vitro transformation of 3T3 cells and in vivo induction of Abelson disease.

Main Results:

• Intrathymic A-MuLV injection successfully induced thymomas in both mouse strains with short latent periods.
• BALB/c thymomas were predominantly Thy-1-, while C57BL/Ka thymomas were Thy-1+.
• Cloned cell lines exhibited varying Thy-1 expression, with one line expressing Lyt-1.
• Virus from cloned lines demonstrated transforming ability in vitro and induced disease in vivo.
• The A-MuLV p120 protein was detected in a cloned Thy-1+ line.

Conclusions:

• A-MuLV is capable of inducing thymomas when administered directly into the thymus.
• These findings indicate that A-MuLV can transform cells within the T lymphocyte lineage.
• The study highlights the potential of A-MuLV as a tool for studying T cell development and oncogenesis.