VSIG8-based chimeric proteins
The present invention relates, in part, to chimeric proteins which include the extracellular domain of V-set and immunoglobulin domain-containing protein 8 (VSIG8) and their use in the treatment of diseases, such as immunotherapies for cancer and/or inflammatory diseases.
1. A heterologous chimeric protein, wherein the heterologous chimeric protein has a general structure of:
N terminus -(a)-(b)-(c)-C terminus,
wherein:
(a) is a first domain comprising a portion of V-set and immunoglobulin domain-containing protein 8 (VSIG8), the portion of VSIG8 having an amino acid sequence which is at least 97% identical to the amino acid sequence of SEQ ID NO: 2
(b) is a linker of the general structure: (i)-(ii)-(ii), wherein (ii) is an Fc domain, and (i) and (iii) are two joining linkers,
the joining linkers being flexible and independently comprising an amino acid sequence of any one of SEQ ID NOs: 28 to 74; and
(c) is a second domain comprising a portion of OX40 ligand (OX40L) that binds a OX40L receptor,
wherein the joining linkers connect the first domain and the second domain to the Fc domain.
2. The heterologous chimeric protein of claim 1 , wherein the second domain comprises substantially all of the extracellular domain of OX40L.
3. The heterologous chimeric protein of claim 1 , wherein the Fc domain is derived from IgG4.
4. The heterologous chimeric protein of claim 3 , wherein the Fc domain is derived from human IgG4.
5. The heterologous chimeric protein of claim 1 , wherein the portion of VSIG8 is at least 98% identical to the amino acid sequence of SEQ ID NO: 2.
6. The heterologous chimeric protein of claim 5 , wherein the portion of OX40L is at least 95% identical to the amino acid sequence of SEQ ID NO: 3 or SEQ ID NO: 4.
7. The heterologous chimeric protein of claim 6 , wherein the linker comprises an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 25, SEQ ID NO: 26, or SEQ ID NO: 27.
8. The heterologous chimeric protein of claim 7 , wherein one joining linker is N terminal to the Fc domain and another joining linker is C terminal to the Fc domain.
9. A recombinant fusion protein comprising a general structure of:
N terminus -(a)-(b)-(c)-C terminus,
wherein:
(a) is a first domain comprising an extracellular domain of VSIG8 that is at least 97% identical to the amino acid sequence of SEQ ID NO: 2,
(b) is a linker linking the first domain and a second domain and comprising an Fc domain derived from human IgG4, and two joining linker sequences selected from the amino acid sequences of SEQ ID NOs: 28 to 74, wherein one joining linker is N terminal to the Fc domain and another joining linker is C terminal to the Fc domain, and
(c) is the second domain comprising an extracellular domain of OX40 ligand (OX40L) that is at least 95% identical to the amino acid sequence of SEQ ID NO: 4 and binds an OX40L receptor.
10. The recombinant fusion protein of claim 9 , wherein the linker comprises a sequence which is at least 95% identical to the amino acid sequence of SEQ ID NO: 25, SEQ ID NO: 26, or SEQ ID NO: 27.