Methods of designing and producing novel compounds having improved binding affinity for CD154 or other trimeric proteins
The present invention relates to methods for designing and producing novel CD40:CD154 binding interrupter compounds and methods using these compounds to treat conditions associated with inappropriate CD154 activation in a subject. This invention also relates to novel methods for screening candidate compounds for the properties of specifically binding CD154 and interrupting CD40:CD154 interaction. This invention further relates to methods of improving the binding affinity, or the ability to block CD40/CD154 interaction, of a synthetic molecule for a trimeric protein, such as CD154. These methods comprise converting a first synthetic molecule that cannot promote lattice or aggregate formation of its target trimeric protein to a second synthetic molecule that can promote lattice or aggregate formation of its target trimeric protein. This invention also relates to a two-dimensional lattice or aggregate comprising a plurality of trimeric CD154 on a cell surface or in solution, wherein the lattice or aggregate is formed by bivalent anti-CD154 antibodies associated with trimeric CD154 molecules.
1 . A multi-molecular, two-dimensional lattice or aggregate comprising:
(a) a plurality of trimeric CD154 molecules disposed on the extracellular surface of a cell membrane; and
(b) anti-CD154 monoclonal antibody molecules, or antigen-binding fragments thereof, each cross-linking said plurality of trimeric CD154 molecules such that a lattice or aggregate is formed on the extra-cellular surface of said cell membrane.
2 . A multi-molecular, two-dimensional lattice or aggregate comprising:
(a) a plurality of trimeric CD154 molecules in solution; and
(b) anti-CD154 monoclonal antibody molecules, or antigen-binding fragments thereof, each cross-linking said plurality of trimeric CD154 molecules such that a lattice or aggregate is formed in solution.
3 . The multi-molecular, two-dimensional lattice or aggregate according to claim 1 , wherein said cell membrane is a mammalian cell membrane.
4 . The multi-molecular lattice or aggregate according to claim 1 or 2 , wherein said anti-CD154 monoclonal antibody molecules, or antigen-binding fragments thereof, interrupt the binding of CD154 to CD40.
5 . The multi-molecular lattice or aggregate according to claim 1 or 2 , wherein said CD154 monoclonal antibody molecules specifically bind to the 5c8 antigen, which is specifically bound by monoclonal antibody 5c8 (produced by the hybridoma having ATCC Accession No. HB 10916).
6 . A method for improving the binding affinity of a first synthetic molecule for a trimeric protein by generating a second synthetic molecule therewith, comprising the steps of:
(a) providing a first synthetic molecule that binds a trimeric protein with low affinity and is not capable of cross-linking a plurality of said trimeric protein and thereby promoting a plurality of said trimeric protein on a cell surface to form a lattice or aggregate;
(b) providing a means to generate a second synthetic molecule comprising said first synthetic molecule, wherein said second synthetic molecule is capable of cross-linking a plurality of said trimeric protein and promoting a plurality of said trimeric proteins on a cell surface to form a lattice or aggregate; and
(c) generating said second synthetic molecule based on said means.
7 . A method for improving the binding affinity of a first synthetic molecule for a trimeric protein by generating a second synthetic molecule therewith, comprising the steps of:
(a) providing a first synthetic molecule that binds a trimeric protein with low affinity and is not capable of cross-linking a plurality of said trimeric protein and thereby promoting a plurality of said trimeric proteins in solution to form a lattice or aggregate;
(b) providing a means to generate a second synthetic molecule comprising said first synthetic molecule, wherein said second synthetic molecule is capable of cross-linking a plurality of said trimeric protein and promoting a plurality of said trimeric protein in solution to form a lattice or aggregate; and
(c) gene rating said second synthetic molecule based on said means.
8 . The method according to claim 6 or 7 , wherein said trimeric protein is a protein other than CD154.
9 . The method according to claim 8 , wherein said trimeric protein is a TNF family member protein.
10 . The method according to claim 6 or 7 , wherein said trimeric protein is CD154.
11 - 18 . (canceled)
19 . A method for screening a candidate compound for the property of interrupting CD40:CD154 interaction, comprising the steps of:
(a) providing a cell having trimeric CD154 molecules on the cell surface;
(b) incubating said cell with said candidate compound, under conditions sufficient for said compound to promote cross-linking of said CD154 molecules if said compound has the property of promoting such cross-linking; so as to produce a lattice or aggregate of CD154 molecules on the cell surface;
(c) incubating said cell with a detectable agent that specifically binds to cell surface CD154 molecules; and
(d) detecting that a lattice or aggregate of cross-linked CD154 molecules has formed on the cell surface.
20 . A method for screening a candidate compound for the property of interrupting CD40:CD154 interaction, comprising the steps of:
(a) providing a solution comprising trimeric CD154 molecules;
(b) incubating said solution with said candidate compound, under conditions sufficient for said compound to promote cross-linking of said trimeric CD154 molecules in solution if said compound has the property of promoting such cross-linking; so as to produce a lattice or aggregate of CD154 molecules in solution; and
(c) detecting that a lattice or aggregate of cross-linked CD154 molecules has formed in solution.
21 . The met hod according to claim 19 , wherein said detectable agent is a monoclonal antibody.
22 . The method according to claim 19 , wherein said detectable agent is directly linked to a fluorochrome.
23 . The method according to claim 19 , wherein said detectable agent is indirectly linked to a fluorochrome via a secondary reagent that is linked to a fluorochrome.
24 . The method according to claim 19 , wherein said cell is a T lymphocyte.
25 . The method according to claim 19 , wherein said cell is an immortalized T cell.
26 . The method according to claim 25 , wherein said immortalized T cell is a D1.1 cell derived from ATCC Deposit No. CRL 10915.
27 . The method according to claim 19 or claim 20 , further comprising the step of:
(e) confirming whether the candidate compound capable of promoting lattice or aggregate formation also is capable of interrupting CD40:CD154 interaction.
28 . The method according to claim 27 , wherein step (e) is performed using an in vitro assay for T cell activation of B cells.
29 . The method according to claim 27 , wherein step (e) is performed using an in vitro assay for immunoglobulin production by B cells.
30 . The method according to claim 27 , wherein step (e) is performed using an in vivo assay for inhibition of a humoral immune response.
31 . A method for screening a candidate compound for the property of interrupting CD40:CD154 interaction, comprising the steps of:
(a) providing a cell having trimeric CD154 molecules on the cell surface;
(b) incubating said cell with said candidate compound, under conditions sufficient for said compound to promote cross-linking of said CD154 molecules if said compound is capable of promoting such cross-linking; so as to produce a lattice or aggregate of CD154 molecules on the cell surface; and
(c) detecting that a lattice or aggregate of cross-linked CD154 molecules has formed on the cell surface by a cell-binding assay.
32 . A method for screening a candidate compound for the property of interrupting CD40:CD154 interaction, comprising the steps of:
(a) providing a solution comprising trimeric CD154 molecules in solution;
(b) incubating said solution with said candidate compound, under conditions sufficient for said compound to promote cross-linking of said CD154 molecules if said compound is capable of promoting such cross-linking; so as to produce a lattice or aggregate of CD154 molecules in solution; and
(c) detecting that a lattice or aggregate of cross-linked CD154 molecules has formed on the cell surface by an assay selected from the group consisting of gel filtration assay and light scattering assay.
33 . The method according to claim 31 or 32 , further comprising the step of:
(d) confirming whether the candidate compound capable of promoting lattice or aggregate formation also has the property of interrupting CD40:CD154 interaction.
34 - 53 . (canceled)