CD80 variant immunomodulatory proteins and uses thereof
Provided herein are variant CD80 polypeptides, immunomodulatory proteins comprising variant CD80 polypeptides, and nucleic acids encoding such proteins. The immunomodulatory proteins provide therapeutic utility for a variety of immunological and oncological conditions. Compositions and methods for making and using such proteins are provided.
1 . A nucleic acid molecule encoding a CD80-Fc immunomodulatory protein of the formula CD80-linker-Fc, wherein:
CD80 is a variant CD80 polypeptide comprising an amino acid substitution at position 68 in an unmodified CD80 polypeptide set forth in SEQ ID NO:28 or a portion thereof comprising an IgV domain, wherein the amino acid substitution at position 68 is V68M or V68A, and wherein the variant CD80 polypeptide comprises a sequence of amino acids that exhibits at least 90% sequence identity to the sequence set forth in SEQ ID NO:28 or the portion of SEQ ID NO: 28 comprising an IgV domain; and
the variant CD80 polypeptide specifically binds to the ectodomain of human PD-L1 with increased binding affinity compared to the binding of the unmodified CD80 polypeptide to the ectodomain of human PD-L1.
2 . A vector, comprising the nucleic acid molecule of claim 1 .
3 . A cell comprising the vector of claim 2 .
4 . A method of producing a CD80-Fc immunomodulatory protein, comprising introducing a nucleic acid molecule encoding the CD80-Fc immunomodulatory protein of the formula CD80-linker-Fc or a vector comprising the nucleic acid molecule into a host cell under conditions to express the protein in the host cell, wherein:
CD80 is a variant CD80 polypeptide comprising an amino acid substitution at position 68 in an unmodified CD80 polypeptide set forth in SEQ ID NO:28 or a portion thereof comprising an IgV domain, wherein the amino acid substitution at position 68 is V68M or V68A, and wherein the variant CD80 polypeptide comprises a sequence of amino acids that exhibits at least 90% sequence identity to the sequence set forth in SEQ ID NO:28 or the portion of SEQ ID NO: 28 comprising an IgV domain; and
the variant CD80 polypeptide specifically binds to the ectodomain of human PD-L1 with increased binding affinity compared to the binding of the unmodified CD80 polypeptide to the ectodomain of human PD-L1.
5 . The method of claim 4 , further comprising isolating or purifying the CD80-Fc immunomodulatory protein from the host cell.
6 . An infectious agent, comprising the nucleic acid molecule of claim 1 .
7 . The infectious agent of claim 6 , wherein the infectious agent is a virus, wherein the virus is an oncolytic virus.
8 . A pharmaceutical composition, comprising the infectious agent of claim 6 and a pharmaceutically acceptable excipient.
9 . The nucleic acid molecule of claim 1 , wherein the IgV domain is amino acids 35-135, 35-138, 37-138, or 35-141 of SEQ ID NO:1.
10 . The nucleic acid molecule of claim 1 , wherein the amino acid substitution at position 68 is the amino acid substitution V68M.
11 . The nucleic acid molecule of claim 1 , wherein the variant CD80 polypeptide comprises up to 10 amino acid substitutions.
12 . The nucleic acid molecule of claim 1 , wherein the Fc domain is a variant IgG1 Fc domain with reduced effector function.
13 . The nucleic acid molecule of claim 12 , wherein the variant Fc domain comprises the amino acid substitutions R292C/N297G/V302C, by EU numbering.
14 . The nucleic acid molecule of claim 12 , wherein the variant Fc domain comprises the amino acid substitutions L234A/L235E/G237A, by EU numbering.
15 . The nucleic acid molecule of claim 1 , wherein the Fc domain is an Fc domain of IgG2.
16 . The nucleic acid molecule of claim 1 , wherein the Fc domain is an Fc domain of IgG4 or is a variant IgG4 Fc domain containing a S228P mutation, by EU numbering.
17 . The nucleic acid molecule of claim 1 , wherein the variant CD80 polypeptide comprises the amino acid substitution V68M, wherein the portion of the CD80 polypeptide set forth in SEQ ID NO:28 comprising the IgV domain is amino acids 35-141 of SEQ ID NO:28.
18 . The nucleic acid molecule of claim 1 , wherein the variant CD80 polypeptide comprises a sequence of amino acids that exhibits at least 95% sequence identity to the sequence set forth in SEQ ID NO:28 or the portion of SEQ ID NO:28 comprising an IgV domain.
19 . The nucleic acid molecule of claim 1 , wherein the variant CD80 polypeptide comprises a sequence of amino acids that exhibits at least 95% sequence identity to the sequence set forth as amino acids 35-141 of SEQ ID NO: 1.
20 . The nucleic acid molecule of claim 17 , wherein the variant CD80 polypeptide comprises a sequence of amino acids that exhibits at least 95% sequence identity to the sequence set forth as amino acids 35-141 of SEQ ID NO: 1.