HERV-K (HML-2) Env analog fusion proteins for antigen specific immunotherapy and methods of use
Recombinantly manufactured fusion proteins comprising a HERV-K (HML-2) Env protein fragment or an analog thereof linked to a human Fc fragment are described. The fusion proteins may be administered to patients having a disease or a disorder with the intention of mitigating and/or reducing the duration of symptoms associated with the condition or disease (for example but not limited to muscular weakness, paralysis and respiratory failure), and/or preventing symptoms associated with the condition or disease, for example, by preventing motor neuron degeneration and cell death in amyotrophic lateral sclerosis (ALS) patients associated with the condition or disease. Improvement after treatment may be manifested as a decrease or elimination of such symptoms, for example, by a decrease or elimination of symptoms associated with ALS, and/or by a decrease in the duration of such symptoms.
1 . A fusion protein comprising a human endogenous retrovirus K (HERV-K) subgroup human endogenous mouse mammary tumor virus-like type 2 (HML-2) envelope protein (Env) analog (“HERV-K (HML-2) Env analog”) and an Fc fragment, wherein the HERV-K (HML-2) Env analog and the Fc fragment are connected by a peptide linker, wherein the HERV-K (HML-2) Env analog consists of the following sequence:
(SEQ ID NO: 24)
GQFYHNCSGQTQSCPSAQVSPAVDSDLTESLDKHKHKKLQSFYPWEWGE
K.
2 . The fusion protein of claim 1 , wherein the Fc fragment comprises the following sequence:
(SEQ ID NO: 1)
DKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHE
DPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKE
YKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTC
LVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSR
WQQGNVFSCSVMHEALHNHYTQKSLSLSPG.
3 . The fusion protein of claim 1 , wherein the linker comprises the following sequence:
(SEQ ID NO: 2)
GGGSGGGS.
4 . The fusion protein of claim 1 , wherein the fusion protein comprises the following sequence:
(SEQ ID NO: 46)
GQFYHNCSGQTQSCPSAQVSPAVDSDLTESLDKHKHKKLQSFYPWEWGE
KGGGSGGGSDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVT
CVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVL
HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDEL
TKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLY
SKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPG.
5 . The fusion protein of claim 1 , wherein the Fc fragment is glycosylated.
6 . An immunogenic composition comprising the fusion protein of claim 1 and a pharmaceutically acceptable carrier.
7 . The immunogenic composition of claim 6 , further comprising an adjuvant.
8 . A method for increasing antibody production in a subject against an antigenic agent comprising a HERV-K (HML-2) Env analog, the method comprising administering a therapeutically effective amount of the fusion protein of claim 1 to said subject.
9 . The method of claim 8 , wherein the subject is antibody naïve to the antigenic agent prior to administration of the fusion protein.
10 . The method of claim 8 , wherein the subject has a measurable antibody titer against said antigenic agent prior to administration of the fusion protein.
11 . The method of claim 8 , wherein the fusion protein is administered via injection.
12 . The method of claim 8 , wherein the fusion protein is administered subcutaneously or intramuscularly.
13 . The method of claim 8 , wherein the fusion protein is co-administered with an adjuvant.
14 . A method of producing the fusion protein of claim 1 , said method comprising transiently transfecting a nucleic acid encoding for the fusion protein into a Chinese hamster ovary (CHO) cell expression system, wherein the transfected CHO cell expression system expresses the fusion protein, and wherein the yield of the purified or isolated fusion protein from the transfected CHO cell expression system is greater than 50 mg/L.
15 . An isolated cell engineered to express the fusion protein of claim 1 .
16 . A cDNA encoding the fusion protein of claim 1 .
17 . A fusion protein comprising a human endogenous retrovirus K (HERV-K) subgroup human endogenous mouse mammary tumor virus-like type 2 (HML-2) envelope protein (Env) analog (“HERV-K (HML-2) Env analog”) and an Fc fragment, wherein the HERV-K (HML-2) Env analog and the Fc fragment are connected by a peptide linker, wherein the HERV-K (HML-2) Env analog consists of the following sequence:
(SEQ ID NO: 25)
SPVSGPEHPELWRLTVASHHIRIWSGNQTLETRDRKPFYT.
18 . The fusion protein of claim 17 , wherein the Fc fragment comprises the following sequence:
(SEQ ID NO: 1)
DKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHE
DPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKE
YKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTC
LVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSR
WQQGNVFSCSVMHEALHNHYTQKSLSLSPG.
19 . The fusion protein of claim 17 , wherein the fusion protein comprises the following sequence:
(SEQ ID NO: 47)
SPVSGPEHPELWRLTVASHHIRIWSGNQTLETRDRKPFYTGGGSGGGSD
KTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHED
PEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEY
KCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCL
VKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRW
QQGNVFSCSVMHEALHNHYTQKSLSLSPG.
20 . A fusion protein consisting of the sequence of SEQ ID NO: 46 or SEQ ID NO:47 or pharmaceutical composition thereof.