Production in plants of ricin antibodies that bind to ricin B chain

A method of making an antibody or antibody fragment in a plant that binds to ricin B chain comprising:

• (a) introducing a nucleic acid molecule encoding a heavy chain variable region of the antibody and a nucleic acid molecule encoding a light chain variable region of the antibody into a plant or plant cell;
• (b) introducing a nucleic acid molecule encoding a P19 suppressor of gene-silencing protein into the plant or plant cell;
• and
• (c) growing the plant or plant cell to obtain a plant that expresses the antibody or antibody fragment,
• wherein the nucleic acid molecule encoding the heavy chain variable region and the nucleic acid molecule encoding the light chain variable region of the antibody are introduced on the same T-DNA vector, the T-DNA vector comprising a left border and a right border,
• wherein the nucleic acid molecule encoding the heavy chain variable region and the nucleic acid molecule encoding the light chain variable region are in opposite and divergent transcriptional orientations,
• wherein the nucleic acid molecule encoding the heavy chain variable region is between the left border and the nucleic acid molecule encoding the light chain variable region,
• wherein the nucleic acid molecule encoding the light chain variable region is between the nucleic acid molecule encoding the heavy chain variable region and the right border,
• wherein the nucleic acid molecule encoding the P19 suppressor of gene-silencing protein is introduced on a separate vector from the T-DNA vector comprising the nucleic acid molecule encoding the heavy chain variable region and the nucleic acid molecule encoding the light chain variable region of the antibody,
• and
• wherein the nucleic acid molecule encoding the heavy chain variable region comprises the Complementarity Determining Region (CDR) H1 sequence as shown in SEQ ID NO:
• 2, the CDR H2 sequence as shown in SEQ ID NO:
• 3, and the CDR H3 sequence as shown in SEQ ID NO:
• 4 or the heavy chain variable region comprises the amino acid sequence of CDR H1 as shown in SEQ ID NO:
• 6, the amino acid sequence of CDR H2 as shown in SEQ ID NO:
• 7, and the amino acid sequence of CDR H3 as shown in SEQ ID NO:
• 8 and
• wherein the nucleic acid molecule encoding the light chain variable region comprises the CDR Li sequence as shown in SEQ ID NO:
• 10, the CDR L2 sequence as shown in SEQ ID NO:
• 11, and the CDR L3 sequence as shown in SEQ ID NO:
• 12 or the light chain variable region comprises the amino acid sequence of CDR L1 as shown in SEQ ID NO:
• 14, the amino acid sequence of CDR L2 as shown in SEQ ID NO:
• 15, and the amino acid sequence of CDR L3 as shown in SEQ ID NO:
• 16.