ICAM-1/LFA-1 short-chain peptides and method of using same

A modulator peptide, wherein the modulator peptide, when bound to a human LFA-1 molecule, increases the binding affinity of a blocking peptide for the LFA-1 molecule by inducing a conformational change in the LFA-1 molecule, and the blocking peptide, when bound to the LFA-1 molecule, inhibits the binding of the LFA-1 molecule to a human ICAM-1 molecule, wherein the modulator peptide comprises an amino acid sequence included in the amino acid sequence of the extracellular segment of the ICAM-1 molecule and has a molecular weight under 20 kilodaltons, wherein the modulator peptide is prepared by a method comprising the steps of:

• (a) identifying a protein domain of the ICAM-1 molecule wherein the protein domain is capable of binding to the LFA-1 molecule;
• and
• (b) synthesizing the modulator peptide comprising an amino acid sequence included in the protein domain, and
• wherein, in the binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the modulator peptide is at least 10% lower than the fluorescence intensity value calculated using a second sample including the modulator peptide.

A peptide composition effective in inhibiting the binding of a human ICAM-1 molecule to a human LFA-1 molecule, wherein the peptide composition comprises:

• a blocking peptide, wherein the blocking peptide has an initial binding affinity for the ICAM-1 molecule, and, when bound to the ICAM-1 molecule, inhibits the binding of the ICAM-1 molecule to the LFA-1 molecule;
• and
• a modulator peptide, wherein the modulator peptide, when bound to the ICAM-1 molecule, increases the binding affinity of the blocking peptide for the ICAM-1 molecule by inducing a conformational change in the ICAM-1 molecule,
• wherein the blocking peptide and the modulator peptide each comprise an amino acid sequence included in the amino acid sequence of the extracellular segment of the LFA-1 molecule and each have molecular weights of under 20 kilodaltons,
• wherein the blocking peptide is prepared by a method comprising the steps of:
• (a) identifying a first protein domain of the LFA-1 molecule wherein the first protein domain is capable of binding to the ICAM-1 molecule;
• and
• (b) synthesizing a blocking peptide comprising an amino acid sequence included in the first protein domain,
• wherein, in the antibody-binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the blocking peptide is at least 10% higher than the fluorescence intensity value calculated using a second sample including the blocking peptide,
• wherein the modulator peptide is prepared by a method comprising the steps of:
• (c) identifying a second protein domain of the LFA-1 molecule wherein the second protein domain is capable of binding to the ICAM-1 molecule;
• and
• (d) synthesizing the modulator peptide comprising an amino acid sequence included in the second protein domain,
• wherein, in the binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the modulator peptide is at least 10% lower than the fluorescence intensity value calculated using a second sample including the modulator peptide.

A peptide composition effective in inhibiting the binding of a human ICAM-1 molecule to a human LFA-1 molecule, wherein the peptide composition comprises:

• a blocking peptide, wherein the blocking peptide has an initial binding affinity for the ICAM-1 molecule, and, when bound to the ICAM-1 molecule, inhibits the binding of the ICAM-1 molecule to the LFA-1 molecule;
• and
• a modulator peptide, wherein the modulator peptide, when bound to the ICAM-1 molecule, increases the binding affinity of the blocking peptide for the ICAM-1 molecule by inducing a conformational change in the ICAM-1 molecule,
• wherein the blocking peptide comprises an amino acid sequence included in the amino acid sequence of the extracellular segment of the LFA-1 molecule and each have molecular weights of under 20 kilodaltons,
• wherein the modulator peptide comprises the amino acid sequence of Sequence ID No. 16,
• wherein the blocking peptide is prepared by a method comprising the steps of:
• (a) identifying a first protein domain of the LFA-1 molecule wherein the first protein domain is capable of binding to the ICAM-1 molecule;
• and
• (b) synthesizing a blocking peptide comprising an amino acid sequence included in the first protein domain, and
• wherein, in the antibody-binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the blocking peptide is at least 10% higher than the fluorescence intensity value calculated using a second sample including the blocking peptide.

A peptide composition effective in inhibiting the binding of a human LFA-1 molecule to a human ICAM-1 molecule, wherein the peptide composition comprises:

• a blocking peptide, wherein the blocking peptide has an initial binding affinity for the LFA-1 molecule, and, when bound to the LFA-1 molecule, inhibits the binding of the LFA-1 molecule to the ICAM-1 molecule;
• and
• a modulator peptide, wherein the modulator peptide, when bound to the LFA-1 molecule, increases the binding affinity of the blocking peptide for the LFA-1 molecule by inducing a conformational change in the LFA-1 molecule,
• wherein the blocking peptide and the modulator peptide each comprise an amino acid sequence included in the amino acid sequence of the extracellular segment of the ICAM-1 molecule and each have molecular weights of under 20 kilodaltons,
• wherein the blocking peptide is prepared by a method comprising the steps of:
• (a) identifying a first protein domain of the ICAM-1 molecule wherein the first protein domain is capable of binding to the LFA-1 molecule;
• and
• (b) synthesizing a blocking peptide comprising an amino acid sequence included in the first protein domain,
• wherein, in the antibody-binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the blocking peptide is at least 10% higher than the fluorescence intensity value calculated using a second sample including the blocking peptide,
• wherein the modulator peptide is prepared by a method comprising the steps of:
• (c) identifying a second protein domain of the ICAM-1 molecule wherein the second protein domain is capable of binding to the LFA-1 molecule;
• and
• (d) synthesizing the modulator peptide comprising an amino acid sequence included in the second protein domain,
• wherein, in the binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the modulator peptide is at least 10% lower than the fluorescence intensity value calculated using a second sample including the modulator peptide.

A peptide composition effective in inhibiting the binding of a human LFA-1 molecule to a human ICAM-1 molecule, wherein the peptide composition comprises:

• a blocking peptide, wherein the blocking peptide has an initial binding affinity for the LFA-1 molecule, and, when bound to the LFA-1 molecule, inhibits the binding of the LFA-1 molecule to the ICAM-1 molecule;
• and
• a modulator peptide, wherein the modulator peptide, when bound to the LFA-1 molecule, increases the binding affinity of the blocking peptide for the LFA-1 molecule by inducing a conformational change in the LFA-1 molecule,
• wherein the blocking peptide comprises an amino acid sequence included in the amino acid sequence of the extracellular segment of the ICAM-1 molecule and each have molecular weights of under 20 kilodaltons,
• wherein the modulator peptide comprises the amino acid sequence of Sequence ID No. 11,
• wherein the blocking peptide is prepared by a method comprising the steps of:
• (a) identifying a first protein domain of the ICAM-1 molecule wherein the first protein domain is capable of binding to the LFA-1 molecule;
• and
• (b) synthesizing a blocking peptide comprising an amino acid sequence included in the first protein domain, and
• wherein, in the antibody-binding assay of Example 2, the fluorescence intensity value calculated using a first sample lacking the blocking peptide is at least 10% higher than the fluorescence intensity value calculated using a second sample including the blocking peptide.

A peptide composition operable for inhibiting the interaction between ICAM-1 and LFA-1, said composition comprising:

• a blocking peptide comprising a first amino acid sequence of the extracellular segment of one of the human LFA-1 or human ICAM-1 molecule and having a molecular weight of under 20 kilodaltons, said blocking peptide being capable of binding to a target molecule, which is the other of said human LFA-1 or human ICAM-1 molecule, for inhibiting said LFA-1/ICAM-1 interaction,
• said blocking peptide characterized by the property of having a fluorescence intensity value calculated using a first sample lacking said blocking peptide at least 10% higher than the fluorescence intensity value calculated using a second sample including said blocking peptide, in the antibody-binding assay conducted as described in Example 2;
• and
• a modulator peptide comprising a second amino acid sequence of the extracellular segment of said one of the human LFA-1 or human ICAM-1 molecule which is different than said first sequence, and having a molecular weight of under 20 kilodaltons, said modulator peptide being capable of binding to said target molecule for increasing the affinity of said blocking peptide for said target molecule,
• said modulator peptide characterized by the property of having a fluorescence intensity value calculated using a first sample lacking said modulator peptide of at least 10% lower than the fluorescence intensity value calculated using a second sample including said modulator peptide in the binding assay of Example 2.