Compositions and methods including recombinant B lymphocyte cell line including an exogenously incorporated nucleic acid expressing an exogenous membrane immunoglobulin reactive to a first antigen and including an endogenous gene expressing an endogenous secreted immunoglobulin reactive to a second antigen

1. A method for producing at least one immunoglobulin in an isolated cell line comprising:

introducing into at least one isolated B lymphocyte cell line at least one exogenous membrane immunoglobulin reactive to at least one first antigen to produce at least one first isolated B lymphocyte cell line;

selecting the at least one first isolated B lymphocyte cell line expressing the membrane immunoglobulin reactive to the at least one first antigen;

introducing into the at least one first isolated B lymphocyte cell line at least one exogenous nucleic acid encoding one or more secreted immunoglobulins reactive to at least one second antigen to produce at least one isolated recombinant B lymphocyte cell line; and

selecting the at least one isolated recombinant B lymphocyte cell line expressing the one or more secreted immunoglobulin reactive to the at least one second antigen.

2. The method of claim 1 comprising:

selecting the at least one isolated recombinant B lymphocyte cell line expressing the at least one exogenous membrane immunoglobulin reactive to the at least one first antigen.

3. The method of claim 1 comprising:

administering the at least one first antigen to stimulate the at least one isolated recombinant B lymphocyte cell line; and

testing for the presence of the one or more secreted immunoglobulins reactive to the at least one second antigen in the at least one isolated recombinant B lymphocyte cell line.

4. The method of claim 1 comprising:

introducing into the at least one first isolated B lymphocyte cell line at least one exogenous membrane immunoglobulin reactive to the at least one second antigen.

5. The method of claim 1 comprising:

introducing into the at least one isolated recombinant B lymphocyte cell line at least one exogenous nucleic acid sequence encoding one or more secreted immunoglobulins reactive to at least one third antigen to produce at least one isolated second recombinant B lymphocyte cell line;

selecting the at least one isolated second recombinant B lymphocyte cell line expressing the at least one secreted immunoglobulin reactive to the at least one second antigen and the at least one secreted immunoglobulin reactive to the at least one third antigen.

6. The method of claim 5 comprising:

administering the at least one first antigen to stimulate the at least one isolated second recombinant B lymphocyte cell line; and

testing for the presence of the at least one exogenous secreted immunoglobulin reactive to the at least one third antigen in the recombinant B lymphocyte cell line.

7. The method of claim 1 , wherein introducing into the at least one isolated B lymphocyte cell line the at least one exogenous membrane immunoglobulin reactive to the at least one first antigen comprises introducing at least one exogenous membrane immunoglobulin reactive to the at least one first antigen.

8. The method of claim 1 , wherein introducing into the at least one isolated B lymphocyte cell line the at least one exogenous membrane immunoglobulin reactive to the at least one first antigen comprises introducing an exogenous nucleic acid encoding at least one membrane immunoglobulin reactive to the at least one first antigen.

9. The method of claim 4 , wherein introducing into the at least one first isolated B lymphocyte cell line the at least one exogenous membrane immunoglobulin reactive to the at least one second antigen comprises introducing at least one exogenous membrane immunoglobulin polypeptide reactive to the at least one second antigen.

10. The method of claim 4 , wherein introducing into the at least one first isolated B lymphocyte cell line the at least one exogenous membrane immunoglobulin reactive to the at least one second antigen comprises introducing at least one exogenous nucleic acid encoding at least one membrane immunoglobulin reactive to the at least one second antigen.

11. The method of claim 1 comprising:

exposing the at least one isolated recombinant B lymphocyte cell line to the at least one first antigen, and

testing for the activation of the at least one isolated recombinant B lymphocyte cell line to express the exogenous secreted immunoglobulin reactive to the at least one second antigen.

12. The method of claim 11 comprising:

isolating the exogenous secreted immunoglobulin reactive to the at least one second antigen from the at least one isolated recombinant B lymphocyte cell line or from a culture of the at least one isolated recombinant B lymphocyte cell line.

13. The method of claim 1 , wherein activating the at least one exogenously incorporated membrane immunoglobulin with the first antigen is capable of controlling expression of the at least one exogenously incorporated nucleic acid encoding at least one secreted immunoglobulin reactive to the second antigen.

14. The method of claim 1 , wherein

the at least one isolated B lymphocyte cell line comprises at least one of naïve B lymphocytes, immature B lymphocytes, transitional B lymphocytes, mature B lymphocytes, follicular B lymphocytes, memory B lymphocytes, plasmablasts, or plasma cells.

15. The method of claim 1 , wherein

the at least one isolated B lymphocyte cell line comprises at least one memory B lymphocyte.

16. A method for producing at least one immunoglobulin in an isolated cell line comprising:

introducing into at least one first isolated B lymphocyte cell line at least one exogenous nucleic acid encoding one or more secreted immunoglobulins reactive to at least one first antigen to produce at least one isolated recombinant B lymphocyte cell line;

selecting the at least one isolated recombinant B lymphocyte cell line expressing the one or more secreted immunoglobulin reactive to the at least one first antigen;

introducing into the at least one isolated B lymphocyte cell line at least one exogenous membrane immunoglobulin reactive to at least one second antigen to produce at least one first isolated B lymphocyte cell line; and

selecting the at least one first isolated B lymphocyte cell line expressing the membrane immunoglobulin reactive to the at least one second antigen.