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`W0 96/2701 1
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`PCT/US96101598
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`The invention also provides a heteromultimer (such as a bispecific
`antibody,
`bispecific immunoadhesin or
`antibody/immunoadhesin chimera)
`comprising a first polypeptide and a second polypeptide which meet at an
`interface. The interface of the first polypeptide comprises a protuberance
`which
`is positionable in a cavity in the
`interface of
`the second
`polypeptide, and the protuberance or cavity, or both, have been introduced
`into the interface of
`the first and second polypeptides respectively.
`The heteromultimer may be provided in the form of a composition further
`comprising a pharmaceutically acceptable carrier .
`
`host cell comprising nucleic acid
`The invention also relates to a
`encoding the heteromultimer of the preceding paragraph wherein the nucleic
`acid encoding the first polypeptide and second polypeptide is present in
`a single vector or in separate vectors.
`The host cell can be used in a
`method of making a heteromultimer which involves culturing the host cell
`so that
`the nucleic acid is expressed and recovering the heteromultimer
`from the cell culture.
`
`In yet a further aspect, the invention provides a method of preparing
`a heteromultimer comprising:
`(a)
`altering a first nucleic acid encoding a first polypeptide so
`that an amino acid residue in the interface of the first polypeptide is
`replaced with an amino acid residue having a larger side chain volume,
`thereby generating a protuberance on the first polypeptide;
`(b)
`altering a second nucleic acid encoding a second polypeptide
`so that an amino acid residue in the interface of
`the second polypeptide
`is replaced with an amino acid residue having a smaller side chain volume,
`thereby generating a cavity in the
`second polypeptide, wherein the
`protuberance is positionable in the cavity;
`(c)
`introducing into a host cell the first and second nucleic acids
`and culturing the host cell so that expression of
`the first and second
`nucleic acid occurs;
`and
`
`(d)
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`recovering the heteromultimer formed from the cell culture.
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`the heteromultimer recovered from recombinant
`the yields of
`Preferably,
`cell culture are at least greater than 80% and preferably greater than 90%
`compared to the by-product homomultimer (s) .
`
`Brief Description of the Drawings
`1 depicts the various antibody molecules which may be generated
`Fig.
`when the traditional hybrid—hybridoma technique of Millstein and Cuello,
`supra, is used for making full length BsAbs.
`Figs. 2A-2E illustrate the various techniques of the background art
`for manufacturing BsAb fragments, reviewed in the background section above.
`Figs. 3A-3C depict an exemplary strategy for making an immunoadhesin
`(Fig. 3C) comprising the binding domain of a receptor (Fig. 3A) and
`dimer
`the constant domain of an IgG1 immunoglobulin (Fig. 3B).
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