NEW MONOCLONAL ANTIBODIES AGAINST THE RECEPTOR DEC-205 OF CHICKEN DENDRITIC CELLS

The invention relates to the production and the characterization of new murine monoclonal antibodies that recognize the domain CTDL-2 (SEQ ID NO: 1) of the cell receptor DEC-205 of dendritic cells in chickens (Gallus gallus) located at the surface of dendritic cells. The selected segment defined as CTLD-2 (SEQ ID NO:1), corresponding to domain 2 similar to Type C lecithins, was successfully expressed and purified in an homogeneous manner so as to be used as an immunogenic in the generation of immune responses in BALBc mice, in order to produce hybridomas which monoclonal antibodies are useful for specifically recognizing said segment. Clones 2F2 and 4D12 were obtained as those with better demonstrated results, since they express antibodies that accurately recognize the segment CTLD-2 (SQ ID NO: 1). From this segment, four lines of hybridomas were derived, amongst which the line 2F2E8D3B6 produces antibodies with the IgG2a lambda isotype that is highly recognized by the domain CTLD-2 in in vitro tests and by the receptor DEC-205 in in vivo tests. On the other hand, the RNA of the H5N2-type avian flu virus was used to produce, in a heterologous manner, the protein Hemaglutinina H5 (SEQ ID NO: 8) of the virus, which was purified and covalently conjugated to the purified antibody of the 2F2E8D3B6 clone, where said conjugate was used for immunizing laying hens. The eggs produced by the immunized hens are useful for isolating chickens (Gallu gallus). These monoclonal antibodies may be used as carriers of any pathogenic antigen against which an effective avian (potentially pig and human) vaccination is to be obtained. As there is a similarity in the sequence of domain 2, which is similar to Lecithin, in the receptors DEC-205 of different vertebrae, the crossed recognition of the antibody 2F2E8D3B6 in human cells and pig and dog spleen was proved. The obtained results indicate that the antibody recognizes the segments CTLD-2 (SEQ ID NO: 1) of the receptor DEC-205 in hum an cells (Homo sapiens) and pig cells (Sus scrofa). However, that of dog is not recognized. This means that the antibody may potentially be used for generating pig and human vaccines. The invention also includes the pharmaceutical compositions of the conjugates for being applied in the veterinary field. La presente invención se refiere a un anticuerpo que reconoce el dominio CTLD-2 del receptor celular DEC-205 de Gallus gallus (SEQ ID NO: 1), caracterizado porque comprende un fragmento VH con la se