Lawsonia derived gene and related flge polypeptides, peptides and proteins and their uses

An isolated or recombinant immunogenic polypeptide selected from the following:

• (i) a peptide, oligopeptide or polypeptide which comprises an amino acid sequence which has at least about 60% sequence identity overall to the amino acid sequence set forth in SEQ ID NO:
• 1;
• (ii) a homologue, analogue or derivative of (i) which mimics a B-cell or T-cell epitope of a Lawsonia spp. IgE polypeptide.

A vaccine composition for the prophylaxis or treatment of infection of an animal by Lawsonia spp., said vaccine composition comprising an immunogenic component which comprises an isolated or recombinant polypeptide having at least about 60% sequence identity overall to the amino acid sequence set forth in SEQ ID NO:

• 1 or an immunogenic homologue, analogue or derivative thereof which is immunologically cross-reactive with Lawsonia intracellularis;
• and one or more carriers, diluents or adjuvants suitable for veterinary or pharmaceutical use.

A vaccine vector that comprises, in an expressible form, an isolated nucleic acid molecule having a nucleotide sequence that encodes an isolated or recombinant immunogenic polypeptide which comprises the amino acid sequence set forth in SEQ ID NO:

• 1, such that said immunogenic polypeptide is expressible at a level sufficient to confer immunity against Lawsonia spp., when administered to a porcine or avian animal.

A polyclonal or monoclonal antibody molecule that is capable of binding specifically to an FlgE polypeptide or a derivative of an FlgE polypeptide that is derived from Lawsonia spp. and has at least about 60% sequence identity overall to the amino acid sequence set forth in SEQ ID NO:

• 1.

A method of detecting Lawsonia intracellularis or related microorganism in a biological sample derived from a porcine or avian animal subject, said method comprising the steps of hybridising one or more probes or primers derived from the nucleotide sequence set forth in SEQ ID NO:

• 2 or a complementary nucleotide sequence thereto to said sample and then detecting said hybridisation using a detection means.

A probe or primer having at least about 15 contiguous nucleotides in length derived from SEQ ID NO:

• 2 or a complementary nucleotide sequence thereto.

A plasmid designated pALK11 (ATCC Accession No. 207156).