Novel CD3-epsilon/delta and IFNαR1/R2 heterodimer proteins are bioactive for in vitro assays and immunogenic in eliciting diverse antibodies in mice

Many immune receptors form heterodimers on immune cell surfaces that are crucial for their functions.  CD3 complex is assembled by pairwise interactions of CD3 epsilon with either CD3 delta or CD3 gamma. CD3-epsilon/delta (CD3ε/δ) and CD3-epsilon/gamma (CD3ε/γ) complexes are essential for T-cell activation and signaling. These molecules are key targets for biotherapeutic drugs such as T-cell engagers in multi-specific antibodies.  Type I interferons play a crucial role in regulating immune responses through IFNα/β receptor (IFNαR).  IFNαR is a heterodimer complex composed of IFNαR1 and IFNαR2 subunits on the cell surface for the cytokine to initiate signaling cascade.   To mimic the dimeric conformation of CD3ε/δ and IFNαR, we engineered novel CD3ε/δ and IFNαR1/R2 cis-heterodimer recombinant proteins as antigens for in vitro assays and in vivo immunizations.