Human lymphotoxin and derivatives thereof, process for its preparation, and pharmaceutical composition containing it

Claim 2

A process for preparing human lymphotoxin, which process comprises: (a) obtaining an extract, supernatant or filtrate from a cell culture which produces lymphotoxin; (b) treating said extract, supernatant, or filtrate with a lentil lectin absorbant; (c) selectively eluting the lymphotoxin from the absorbant.

Claim 3

The process of claim 1 which includes, before step (b) the additional step of isoelectric focusing.

Claim 4

The process of claim 1 or claim 2 which includes, before or after the step of isoelectric focusing (if present), the additional step of DEAE-cellulose chromatography.

Claim 5

A process for preparing lymphotoxin, which process comprises: (a) concentrating the extract, supernatant or filtrate from a cell culture which produces lymphotoxin and dialyzing the concentrate to obtain a dialyzate; (b) subjecting the dialyzate to DEAE-cellulose chromatography; (c) subjecting the fraction containing lymphotoxin from step (b) to concentration; (d) subjecting the resultant of (c) to isoelectric focusing to obtain a fraction containing lymphotoxin; (e) subjecting the fraction containing lymphotoxin from step (d) to lentil lectin chromatography; (f) recovering lymphotoxin from step (e). 5. The process of claim 4 wherein the dialysis in step (b) is performed using Pellicon.

Claim 6

The process of claim 4 or claim 5 wherein the lymphotoxin in step (f) is obtained by selectively eluting with a solution containing mannose or galactose.

Claim 7

The process of any one of the preceding claims wherein the cell culture is of a human lymphoblastoid cell line.

Claim 8

The process of claim 7 wherein the cell line is RPMI 1788.

Claim 9

The process of any one of the preceding claims wherein the cell culture has been grown in serum free medium.

Claim 10

Human lymphotoxin and salts and derivatives thereof, substantially free of impurities.

Claim 11

Human lymphotoxin and salts and derivatives thereof, substantially free of impurities.

Claim 12

Human lymphotoxin and salts and derivatives thereof, with a specific activity greater than 10 X 10 6 units/mg. 12. Human lymphotoxin and salts and derivatives thereof, with a specific activity greater than 100 X 10 6 units/mg.

Claim 13

Human lymphotoxin and salts and derivatives thereof, with a specific activity greater than 10 X 10 6 units/mg. 12. Human lymphotoxin and salts and derivatives thereof, with a specific activity greater than 100 X 10 6 units/mg.

Claim 14

A protein and salts and derivatives thereof, which is active in standard assays for lymphotoxin and which is substantially homogeneous with respect to HPLC performed as described in the herein specification.

Claim 15

A protein and salts and derivatives thereof, which is active in standard assays for lymphotoxin and which is substantially homogeneous with respect to HPLC performed as described in the herein specification.

Claim 16

A protein and salts and derivatives thereof, which is active in standard assays for lymphotoxin and which is substantially homogeneous with respect to SDS-PAGE performed as described in the herein specification.

Claim 17

A protein and salts and derivatives thereof, which is active in standard assays for lymphotoxin and which is substantially homogeneous with respect to SDS-PAGE performed as described in the herein specification.

Claim 18

A composition of matter which comprises a tryptic digest of the protein of any one of claims 10 to 14.

Claim 19

A pharmaceutical composition useful for treating tumors in humans which comprises a therapeutically effective amount of a compound of any one of claims 10 to 15 or a pharmaceutically acceptable salt or derivative thereof in admixture with a pharmaceutically acceptable excipient.