Monoclonal antibody production: Fusion of antibody-producing mammalian cells with endlessly replicating tumor cells yields what type of cell line?

Introduction / Context:
The classic hybridoma technology, pioneered by Köhler and Milstein, revolutionized immunology by enabling the production of monoclonal antibodies with a single specificity. Understanding the nature of the fused cell line is essential for biotechnology and diagnostic applications.

Given Data / Assumptions:

• One fusion partner is an antibody-secreting B cell (short-lived).
• The other is a myeloma cell line (immortal but typically non-secreting and HGPRT-).
• Successful fusions are selected (for example, in HAT medium) to recover lines that both secrete antibody and proliferate indefinitely.

Concept / Approach:
Hybridomas inherit immortality from the tumor partner and the antibody gene rearrangements from the B cell. Clonal selection isolates a line producing one antibody specificity in large amounts, underpinning countless assays and therapeutics.

Step-by-Step Solution:

Verification / Alternative check:
Standard protocols show HAT selection rescues HGPRT+ hybrids while eliminating unfused myeloma cells and short-lived B cells.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing the parental myeloma cell line (immortal but non-secreting) with the post-fusion hybridoma that secretes monoclonal antibody.

Final Answer:
Hybridoma.