Antibodies for prevention, treatment and diagnosis of

1. An isolated antibody raised against a chimeric or fusion protein, wherein the chimeric or fusion protein comprises a first peptide joined directly or through a linker to a second peptide or polypeptide, wherein:

(A) said first peptide comprises a region of a Porphyromonas gingivalis trypsin-like enzyme selected from the group consisting of the amino acid sequence that is the same as, or at least 90% homologous to, the sequence shown in any one of SEQ ID NOs: 1-34; and

(B) said second peptide or polypeptide comprises P. gingivalis adhesin domain sequence selected from the group consisting of the amino acid sequence that is the same as, or at least 90% homologous to, the sequence shown in any one of SEQ ID NOs: 35-39;

Wherein the antibody is obtained by a process comprising immunizing a non-human animal with the chimeric or fusion protein, and isolating and purifying the antibody from the non-human animal.

2. The antibody according to claim 1 , wherein the antibody is a monoclonal antibody.

3. A method for the diagnosis or monitoring of a P. gingivalis -related condition or disease in a subject, comprising assaying a biological sample from said subject with the antibody according to claim 1 , to detect the presence of P. gingivalis.

4. The antibody according to claim 1 , wherein said first peptide comprises a sequence selected from the group consisting of SEQ ID NOs: 3-34 and sequences at least 90% homologous thereto.

5. The antibody according to claim 4 , wherein said second peptide or polypeptide comprises a sequence selected from the group consisting of SEQ ID NOs: 35-39 and sequences at least 90% homologous thereto.

6. The antibody according to claim 1 , wherein said first peptide comprises a sequence that is the same as or at least 90% homologous to a sequence selected from the group consisting of SEQ ID NOs: 31-34 and said second peptide or polypeptide comprises a sequence that is the same as or at least 90% homologous to SEQ ID NO: 39.

7. The antibody according to claim 1 , wherein:

the C-terminal residue of said first peptide is covalently linked directly or through a linker that is either (i) up to 15 amino acids in length, or (ii) less than 5 amino acids in length, to either (a) the N-terminal residue of said second peptide or polypeptide or (b) the C-terminal residue of said second peptide or polypeptide, or

the N-terminal residue of said first peptide is covalently linked directly or through a linker that is either (i) up to 15 amino acids in length, or (ii) less than 5 amino acids in length, to either (a) the N-terminal residue of said second peptide or polypeptide or (b) the C-terminal residue of said second peptide or polypeptide.

8. The antibody according to claim 1 , wherein the first peptide comprises a sequence selected from the group consisting of SEQ ID Nos: 27-30 and sequences at least 90% homologous thereto, and said second polypeptide comprises a sequence selected from SEQ ID NO: 36-37 and sequences at least 90% homologous thereto.

9. The antibody according to claim 1 , wherein said first peptide comprises a sequence that is the same as or is at least 90% identical to the sequence of SEQ ID NO: 28 and said second peptide or polypeptide comprises a sequences that is the same or is at least 90% identical to the sequence of SEQ ID NO: 37.

10. The antibody according to claim 1 , wherein said first peptide comprises a sequence that is the same as or is at least 90% identical to the sequence of SEQ ID NO: 27 and said second peptide or polypeptide comprises a sequences that is the same or is at least 90% identical to the sequence of SEQ ID NO: 36.