Protein and process for isolating it

Claim 2

An isolated tissue protein, PP 16 , obtainable by fractionating an aqueous organ extract, the amino acid composition of said tissue protein being: ______________________________________ Variation Amino Acid Mole % Coefficient (%) ______________________________________ Lysine 5.80 9.58 Histidine 2.66 9.26 Arginine 4.35 10.18 Aspartic acid 12.64 4.27 Threonine 4.00 9.01 Serine 6.04 5.16 Glutamic acid 12.54 2.42 Proline 5.37 1.57 Glycine 5.76 6.12 Alanine 6.09 6.44 Cystine/2 2.34 3.57 Valine 5.48 6.16 Methionine 2.25 12.44 Isoleucine 5.68 0.61 Leucine 7.78 3.89 Tyrosine 4.17 3.79 Phenylalanine 5.93 3.96 Tryptophan 1.05 11.42 ______________________________________ said tissue protein further having (a) a carbohydrate content of 4.3±1.6%, comprising 3.4±1.2% of hexoses, 0.24±0.07% of hexosamines, 0.06±0.03% of fucose, and 0.6±0.3% of neuraminic acid; (b) a sedimentation coefficient S 20 ,w 0 of 4.6±0.4 S; (c) a molecular weight, determined in a polyacrylamide gel containing sodium dodecyl-sulfate, of 46,000±3,000; (d) an extinction coefficient E 1 cm 1% (280 nm) of 8.82±0.5; (e) an electrophoretic mobility in the range of albumin; and (f) an isoelectric point of 4.7±0.2.

Claim 3

A tissue protein as claimed in claim 1, wherein said aqueous organ extract is an extract of human placenta, spleen, stomach, or lung.

Claim 4

A tissue protein as claimed in claim 1, wherein said aqueous organ extract is an extract of human placenta.

Claim 5

A process for concentrating the tissue protein PP 16 having the following amino acid analysis: ______________________________________ Variation Amino Acid Mole % Coefficient (%) ______________________________________ Lysine 5.80 9.58 Histidine 2.66 9.26 Arginine 4.35 10.18 Aspartic acid 12.64 4.27 Threonine 4.00 9.01 Serine 6.04 5.16 Glutamic acid 12.54 2.42 Proline 5.37 1.57 Glycine 5.76 6.12 Alanine 6.09 6.44 Cystine/2 2.34 3.57 Valine 5.48 6.16 Methionine 2.25 12.44 Isoleucine 5.68 0.61 Leucine 7.78 3.89 Tyrosine 4.17 3.79 Phenylalanine 5.93 3.96 Tryptophan 1.05 11.42 ______________________________________ said tissue protein further having (a) a carbohydrate content of 4.3±1.6%, comprising 3.4±1.2% of hexoses, 0.24±0.07% of hexosamines, 0.06±0.03% of fucose, and 0.6±0.3% of neuraminic acid; (b) a sedimentation coefficient S 20 ,w 0 of 4.6±0.4 S; (c) a molecular weight, determined in a polyacrylamide gel containing sodium dodecyl-sulfate, of 46,000±3,000; (d) an extinction coefficient E 1 cm 1% (280 nm) of 8.82±0.5; (e) an electrophoretic mobility in the range of albumin; and (f) an isoelectric point of 4.7±0.2, which method comprises subjecting a solution containing this protein to at least one of the following measures and obtaining the fraction enriched in PP 16 : (a) precipitation with ammonium sulfate in the pH range from 5 to 8 and at 30-60% saturation; (b) precipitation with a water-soluble acridine base at a pH value between 4 and 9 and a concentration of 0.2-0.8% (w/v); (c) precipitation of concomitant proteins by adjusting the pH value to 5-6 in a dilute salt solution; (d) preparative zone electrophoresis at pH 8 and isolation of the fraction having the mobility of albumin; (e) gel filtration to obtain proteins in the molecular weight range from 20,000 to 70,000; and (f) adsorption onto a weakly basic ion exchanger and elution of the protein.

Claim 6

A process for concentrating the tissue protein PP 16 having the following amino acid analysis: ______________________________________ Variation Amino Acid Mole % Coefficient (%) ______________________________________ Lysine 5.80 9.58 Histidine 2.66 9.26 Arginine 4.35 10.18 Aspartic acid 12.64 4.27 Threonine 4.00 9.01 Serine 6.04 5.16 Glutamic acid 12.54 2.42 Proline 5.37 1.57 Glycine 5.76 6.12 Alanine 6.09 6.44 Cystine/2 2.34 3.57 Valine 5.48 6.16 Methionine 2.25 12.44 Isoleucine 5.68 0.61 Leucine 7.78 3.89 Tyrosine 4.17 3.79 Phenylalanine 5.93 3.96 Tryptophan 1.05 11.42 ______________________________________ said tissue protein further having (a) a carbohydrate content of 4.3±1.6%, comprising 3.4±1.2% of hexoses, 0.24±0.07% of hexosamines, 0.06±0.03% of fucose, and 0.6±0.3% of neuraminic acid; (b) a sedimentation coefficient S 20 ,w 0 of 4.6±0.4 S; (c) a molecular weight, determined in a polyacrylamide gel containing sodium dodecyl-sulfate, of 46,000±3,000; (d) an extinction coefficient E 1 cm 1% (280 nm) of 8.82±0.5; (e) an electrophoretic mobility in the range of albumin; and (f) an isoelectric point of 4.7±0.2, which method comprises subjecting a solution containing this protein to at least one of the following measures and obtaining the fraction enriched in PP 16 : (a) precipitation with ammonium sulfate in the pH range from 5 to 8 and at 30-60% saturation; (b) precipitation with a water-soluble acridine base at a pH value between 4 and 9 and a concentration of 0.2-0.8% (w/v); (c) precipitation of concomitant proteins by adjusting the pH value to 5-6 in a dilute salt solution; (d) preparative zone electrophoresis at pH 8 and isolation of the fraction having the mobility of albumin; (e) gel filtration to obtain proteins in the molecular weight range from 20,000 to 70,000; and (f) adsorption onto a weakly basic ion exchanger and elution of the protein.

Claim 7

The method of making an antiserum to the protein of claim 1 which comprises immunizing an animal with the protein of claim 1 and recovering serum containing antibodies to said protein.

Claim 8

An antiserum made by the method of claim 5.