IMMORTALIZED MYOBLAST CELL LINES AND USES THEREOF

1 .- 26 . (canceled)

27 . A method of establishing an immortalized human myoblast cell line, said method comprising the steps of:

a) Providing at least one primary human myoblast cell which expresses the surface marker CD56 and optionally the further surface markers CD82 and/or CD146;

b) Transducing said at least one primary human myoblast cell with a lentiviral vector encoding for the cyclin-dependent kinase 4 (CDK4) gene and a lentiviral vector encoding for the catalytic subunit of the human telomerase (hTERT) gene to obtain immortalization of the said primary human myoblast cell;

c) Growing cells from at least one immortalized primary human myoblast cell obtained under step b) in a myoblast cell growth medium and isolating from the growth medium each obtained cell presenting at least one myoblast phenotypic marker in a separate culture medium;

d) Growing separately in individual culture and amplification media each isolated cell obtained under step c);

e) Selecting among all the individual culture and amplification media of step d) at least one cell line with improved stability or expression properties from the parental cell by single cell cloning;

f) Controlling the myogenic potential of the selected at least one cell line;

g) selecting individual clones based on their ability to survive in an encapsulation device;

h) Optionally repeating steps d) to g) sequentially to further improve the selected line.

28 . The method according to claim 27 , wherein step b) is carried out using two separate lentiviral vectors.

29 . An immortalized human myoblast cell line or a composition comprising immortalized human myoblast cells or a progeny thereof derived from primary human myoblast cells, wherein said cells express CDK4 and hTERT and retain myoblast features, in absence of expression of an antibiotic resistance gene.

30 . The immortalized myoblast cell line according to claim 29 , said cell line presenting triple positivity for CD56, CD82 and CD146.

31 . An immortalized human myoblast cell line deposited with CCOS under accession number 1902 or a composition or a progeny thereof.

32 . An immortalized human myoblast cell line or a composition comprising immortalized human myoblast cells or a progeny thereof derived from primary human myoblast cells obtainable from a method according to claim 27 .

33 . A method for the preparation of genetically engineered immortalized human myoblast cells expressing a therapeutic protein under hypoxic conditions, wherein said method comprises the steps of:

i) Providing at least one immortalized primary human myoblast cell;

ii) Transducing said at least one immortalized primary human myoblast cell with a lentiviral vector for the expression of a target protein under the control of a phosphoglycerate kinase (PGK) promoter;

iii) Growing separately in individual culture and amplification media each isolated cell obtained under step ii);

iv) Selecting among all the individual culture and amplification media of step iii) at least one cell line with the highest secretion level for the target protein;

v) Controlling the myogenic potential of the selected at least one cell line.

34 . The method according to claim 33 , wherein the phosphoglycerate kinase (PGK) promoter is a human PGK promoter.

35 . The method according to claim 33 , wherein the target protein is human GM-CSF.

36 . The method according to claim 33 , wherein the target protein is a human monoclonal antibody.

37 . The method according to claim 33 , wherein the target protein selected from rituximab, ipilimumab and gantenerumab.

38 . The method according to claim 33 , wherein the target protein is an antigen, in particular a viral antigen.

39 . The method according to claim 38 , wherein the target protein is a COVID-19 spike protein or an antigenic fragment thereof.

40 . A genetically engineered immortalized human myoblast cell line or a composition comprising said genetically engineered immortalized human myoblast cells or a progeny thereof, wherein said cells express CDK4, hTERT in absence of expression of antibiotic resistance gene and expresses at least one therapeutic protein or antigen, retains myoblast features and are able to secrete said therapeutic protein or antigen.

41 . A genetically immortalized human myoblast cell line secreting GM-CSF deposited with CCOS under accession number 1901 or a composition or a progeny thereof.

42 . A genetically engineered immortalized human myoblast cell line or a composition or a progeny thereof obtainable from a method according to claim 33 .

43 . A pharmaceutical composition comprising at least one immortalized human myoblast cell according to claim 40 and a pharmaceutically acceptable carrier, diluent or excipient thereof.

44 . The pharmaceutical formulation according to claim 43 , wherein said at least one immortalized human myoblast cell is a genetically immortalized human myoblast cell line secreting GM-CSF deposited with CCOS under accession number 1901 or a composition or a progeny thereof.

45 . An implantable biocompatible device or a kit comprising at least one immortalized human myoblast cell according to claim 40 in a cell culture medium, optionally further comprising one or more antigen(s).

46 . The implantable biocompatible device or a kit according to claim 45 , wherein said at least one immortalized human myoblast cell is a genetically immortalized human myoblast cell line secreting GM-CSF deposited with CCOS under accession number 1901 or a composition or a progeny thereof.

47 . A method of treating a disorder or a disease associated in a subject selected from a cancer, an inflammatory disorder, an infectious disease, in a viral infection or a neurodegenerative disorder, said method comprising administering in a subject in need thereof a therapeutically effective amount of genetically engineered immortalized human myoblast cells according to claim 40 .

48 . The method according to claim 47 , wherein said cells are administered as an encapsulated cell preparation.

49 . A method of vaccination against a viral infection in a subject, said method comprising administering in a subject in need thereof a therapeutically effective amount of genetically engineered immortalized human myoblast cells according to claim 40 , wherein said cells express a viral antigen.

50 . The method according to claim 49 , wherein said cancer is selected from non-Hodgkin's lymphoma, head and neck cancer, melanoma, lung, bladder, renal cell carcinoma, triple negative breast cancer, colorectal, gastric, pancreas, ovarian, prostate, sarcoma and chordoma.

51 . The method according to claim 50 , wherein said viral infection is an infection by coronavirus 19 (COVID-19).

52 . The method according to claim 49 , wherein said genetically engineered immortalized human myoblast cells is a genetically immortalized human myoblast cell line secreting GM-CSF deposited with CCOS under accession number 1901 or a composition or a progeny thereof.