Patent ID: 7927817

Claim:
A method for producing a hybrid antibody or hybrid antibody fragment comprising: providing an initial antibody having specificity for a target; determining the sequence of a variable region of the initial antibody; and (i) selecting a first component of the variable region selected from the group consisting of FR1, FR2, FR3 and FR4; comparing the sequence of the first component to sequences contained in a reference database of antibody sequences or antibody fragment sequences from a target species; selecting a first framework sequence from an antibody in the database which is one of the top one hundred hits based on sequence homology to the first component; (ii) selecting a second component of the variable region which is different than the first component, the second component selected from the group consisting of FR1, FR2, FR3 and FR4; comparing the sequence of the second component to sequences contained in a reference database of antibody sequences or antibody fragment sequences from the target species; selecting a second framework sequence from the database which is one of the top one hundred hits based on sequence homology to the second component, wherein the first and second framework sequences selected in step (i) are from different antibodies; and (iii) operatively linking the selected framework sequences to the CDRs and unselected framework sequences of the initial antibody to produce a hybrid antibody or hybrid antibody fragment that has specificity for said target, wherein the framework sequences and CDRs are linked together in the following arrangement: FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4.