Different recombinant murine leukemia viruses use different cell surface receptors

Area of Science:

• Virology
• Molecular Biology
• Immunology

Background:

• Retroviruses are classified into groups based on shared cell surface receptors, determined by viral interference measurements.
• Previous studies identified a common receptor for mink cell focus-inducing (MCF) murine leukemia viruses (MuLVs) on NIH/3T3 cells.

Purpose of the Study:

• To extend the classification of MuLV isolates using viral interference tests.
• To compare the utility of interference tests versus host-range data for virus classification.
• To investigate the receptor usage and generation of recombinant MuLVs.

Main Methods:

• Viral interference assays were performed on NIH/3T3 cells using various MuLV isolates.
• Host-range data was used for comparison with interference test classifications.
• Receptor binding affinities were assessed for different MuLV types.

Main Results:

• All tested MCF MuLV isolates share a distinct receptor on NIH/3T3 cells.
• Interference tests proved superior to host-range data for accurate virus classification.
• A recombinant derived from amphotropic MuLV utilizes a unique receptor, distinct from MCFs.
• Xenotropic MuLV does not interfere with MCFs, indicating no detectable affinity for the MCF receptor.

Conclusions:

• Mouse cells possess multiple endogenous env sequences, leading to diverse recombinant MuLV generation.
• Ecotropic MuLVs primarily generate MCFs, while amphotropic MuLV generates distinct recombinants.
• Recombinant env genes can confer increased pathogenicity compared to their parent viruses.