Circumvention of tolerance for the nuclear T cell protein TCF-1 by immunization of TCF-1 knock-out mice.
Molecular events that underlie the well-defined phenotypic changes of the differentiating thymocyte are poorly understood. A candidate gene to control thymocyte differentiation, T cell factor-1 (TCF-1)* encodes a DNA-binding protein. Its mRNA expression pattern is complex during embryogenesis, yet restricted to lymphocytes postnatally. Expression studies on TCF-1 protein have been hampered by the difficulty to raise antibodies due to extreme evolutionary conservation. TCF-1 knock-out mice, generated recently in our laboratory, have strongly decreased numbers of thymocytes, but are otherwise normal. We have used these mice to generate anti-TCF-1 antibodies. By immunization with a recombinant fusion protein, we show that TCF-1 knock-out mice readily yield antiserum titers against human and mouse TCF-1 protein. Wild-type littermates remain unresponsive to TCF-1 while they mount a high-titer antibody response to the fusion protein, Maltose Binding Protein (MBP). Subsequently, TCF-1-specific hybridomas could be prepared from the spleens of immunized knock-out mice. This study illustrates the almost complete tolerance of mice for human TCF-1 and demonstrates that this tolerance is readily broken by gene knock-out. Furthermore, the usefulness of knock-out mice for the generation of monoclonal antibodies against the gene product of interest is underscored.
Department of Immunology, University Hospital, Utrecht, The Netherlands.
J
J
Castrop
S
S
Verbeek
F
F
Hofhuis
H
H
Clevers
D000818:Animals; D004268:DNA-Binding Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D051538:Hepatocyte Nuclear Factor 1-alpha; D006801:Humans; D007106:Immune Sera / Q000096:biosynthesis; D007108:Immune Tolerance / Q000235:genetics; D007116:Immunization, Passive; D051821:Lymphoid Enhancer-Binding Factor 1; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000276:immunology*; D051822:T Cell Transcription Factor 1; D013601:T-Lymphocytes / Q000276:immunology*; D014157:Transcription Factors / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
D004268:DNA-Binding Proteins; D051538:Hepatocyte Nuclear Factor 1-alpha; C496488:Hnf1a protein, mouse; D007106:Immune Sera; D051821:Lymphoid Enhancer-Binding Factor 1; D011993:Recombinant Fusion Proteins; D051822:T Cell Transcription Factor 1; C497576:TCF7 protein, human; D014157:Transcription Factors