Hybridoma production failure

[Bob Fredrickson]

Recently we failed to grow hybridoma cells.  It appeared that the myeloma 
cells were proliferating at the expense of the hybridomas.  What is the 
most likely explanation?  Is the aminopterin suspect?  Can SP2/0 myeloma 
cells become aminopterin-resistant?  The cells that did grow appeared 
earlier and grew faster than expected and failed to secrete antibody.  Any 
ideas?