Electron Microscopic Study of the Mammary Tumor Agent in Plasma Cell Tumors

Summary

In a previous electron microscopic study of a series of plasma cell tumors induced in BALB/c mice, no intracytoplasmic type-A particles were identified. However, when plasma cell tumors were induced in BALB/c mice which were foster-nursed on C3H mothers to introduce the mammary tumor agent, intracytoplasmic type-A particles were identified in the cells of 7 of the 17 plasma cell tumors induced. This is further evidence for a relationship between the mammary tumor agent and this type of A particle.