Monoclonal antibodies are secreted by immortalized hybridomas made by fusing a B-cell with what type of cell?

Monoclonal antibodies are produced through a process that involves the fusion of a B-cell with a myeloma cell. This fusion creates a hybrid cell known as a hybridoma, which possesses the ability to proliferate indefinitely, a characteristic of myeloma cells, while also retaining the specific antibody-producing capability of the B-cell.

The myeloma cell provides the hybridoma with the advantage of immortality, allowing for the continuous production of the desired antibody. This combination is crucial for generating large quantities of a specific antibody, which is central to various applications in research, diagnostics, and therapeutics.

The other types of cells listed in the other options do not serve the same purpose. T cells are involved in cell-mediated immunity and are not typically used for antibody production. Stem cells and pluripotent cells have the potential to differentiate into many cell types but do not have the specific function required to produce antibodies as efficiently as B-cells fused with myeloma cells. Therefore, the correct answer highlights the specific and necessary role of myeloma cells in the creation of hybridomas for monoclonal antibody production.