Abstract: There is provided a molecule comprising a chain of seven or more contiguous units of 4,6-dideoxy-4-acylamido-?-pyranose each pair of units joined by a C1-C2 or a C1-C3 link, the chain having a terminal end and a reducing end, wherein the pyranose ring in the unit of the chain most distal from the reducing end is linked to a cap structure. The cap structure is not a 4,6-dideoxy-4-acylamido-?-pyranose. There are also provided vaccine compositions comprising the molecule and methods of vaccinating an animal against infection by a Brucella organism, including methods of distinguishing between a vaccinated and an infected animal. There are further provided novel methods of detecting the presence in a sample of an anti-Brucella antibody.

Abstract: There is provided a molecule comprising a chain of seven or more contiguous units of 4,6-dideoxy-4-acylamido-?-pyranose each pair of units joined by a C1-C2 or a C1-C3 link, the chain having a terminal end and a reducing end, wherein the pyranose ring in the unit of the chain most distal from the reducing end is linked to a cap structure. The cap structure is not a 4,6-dideoxy-4-acylamido-?-pyranose. There are also provided vaccine compositions comprising the molecule and methods of vaccinating an animal against infection by a Brucella organism, including methods of distinguishing between a vaccinated and an infected animal. There are further provided novel methods of detecting the presence in a sample of an anti-Brucella antibody.

Abstract: There is provided a molecule comprising a chain of seven or more contiguous units of 4,6-dideoxy-4-acylamido-?-pyranose, each pair of units joined by a C1-C2 or a C1-C3 link, the chain having a terminal end and a reducing end, wherein the pyranose ring in the unit of the chain most distal from the reducing end is linked to a cap structure. The cap structure is not a 4,6-dideoxy-4-acylamido-?-pyranose. There are also provided vaccine compositions comprising the molecule and methods of vaccinating an animal NI against infection by a Brucella organism, including methods of distinguishing between a vaccinated and an infected animal. There are further provided novel methods of detecting the presence in a sample of an anti-Brucella antibody.

Abstract: There is provided a molecule comprising a chain of seven or more contiguous units of 4,6-dideoxy-4-acylamido-?-pyranose, each pair of units joined by a C1-C2 or a C1-C3 link, the chain having a terminal end and a reducing end, wherein the pyranose ring in the unit of the chain most distal from the reducing end is linked to a cap structure. The cap structure is not a 4,6-dideoxy-4-acylamido-?-pyranose. There are also provided vaccine compositions comprising the molecule and methods of vaccinating an animal NI against infection by a Brucella organism, including methods of distinguishing between a vaccinated and an infected animal. There are further provided novel methods of detecting the presence in a sample of an anti-Brucella antibody.

Abstract: There is provided a method of detecting in a sample the presence of an anti-M and/or anti-A and/or anti-C/Y antibody, the method comprising contacting the sample with a diagnostic conjugate provided according to the invention, comprising an oligosaccharide which comprises at least two units of 4,6-dideoxy-4-acylamido-?-pyranose and comprising at least one -(1-3)- link between adjacent 4,6-dideoxy-4-acylamido-?-pyranose units, in which the carbon at position 5 in the pyranose is linked to an R group, where R is independently selected from —CH2OH, —H or an alkyl group having at least one C atom, the oligosaccharide being covalently linked to a non-saccharide molecule or to a surface.

Abstract: There is provided a method of detecting in a sample the presence of an anti-M and/or anti-A and/or anti-C/Y antibody, the method comprising contacting the sample with a diagnostic conjugate provided according to the invention, comprising an oligosaccharide which comprises at least two units of 4,6-dideoxy-4-acylamido-?-pyranose and comprising at least one -(1-3)- link between adjacent 4,6-dideoxy-4-acylamido-?-pyranose units, in which the carbon at position 5 in the pyranose is linked to an R group, where R is independently selected from —CH2OH, —H or an alkyl group having at least one C atom, the oligosaccharide being covalently linked to a non-saccharide molecule or to a surface.

Abstract: There is provided a method of detecting in a sample the presence of an anti-M and/or anti-A and/or anti-C/Y antibody, the method comprising contacting the sample with a diagnostic conjugate provided according to the invention, comprising an oligosaccharide which comprises at least two units of 4,6-dideoxy-4-acylamido-?-pyranose and comprising at least one -(1-3)-link between adjacent 4,6-dideoxy-4-acylamido-?-pyranose units, in which the carbon at position 5 in the pyranose is linked to an R group, where R is independently selected from —CH2OH, —H or an alkyl group having at least one C atom, the oligosaccharide being covalently linked to a non-saccharide molecule or to a surface.

Abstract: There is provided a method of detecting in a sample the presence of an anti-M and/or anti-A and/or anti-C/Y anti-body, the method comprising contacting the sample with a diagnostic conjugate provided according to the invention, comprising an oligosaccharide which comprises at least two units of 4,6-dideoxy-4-acylamido-?-pyranose and comprising at least one -(1-3)-link between adjacent 4,6-dideoxy-4-acylamido-?-pyranose units, in which the carbon at position 5 in the pyranose is linked to an R group, where R is independently selected from —CH2OH, —H or an alkyl group having at least one C atom, the oligosaccharide being covalently linked to a non-saccharide molecule or to a surface.

Abstract: A method for detecting the presence of a diagnostic moiety indicative of exposure to an infectious organism in a biological sample taken from a human or animal, said method comprising use of a first and second fluorescently labelled reagent which are capable of binding to a diagnostic moiety or to a binding partner in competition with a diagnostic moiety, wherein labels on the first and second labelled reagents act as fluorescent donors and acceptors to one another, the proximity of the reagents to one another being detectable by measuring the emission of fluorescent energy from at least one of the labels.

Abstract: A method for detecting the presence of a diagnostic moiety indicative of exposure to an infectious organism in a biological sample taken from a human or animal, said method comprising; (a) adding to said sample a first fluorescently labelled reagent which binds said diagnostic moiety, and a second fluorescently labelled reagent which either binds said diagnostic moiety in addition to said first fluorescently labelled reagent, or which binds the first fluorescently labelled reagent or a complex comprising the first fluorescently labelled reagent in competition to the said diagnostic moiety, wherein a label on one of the first or second fluorescently labelled reagent acts as a fluorescent energy donor compound and wherein the other of the first or second fluorescently labelled reagent acts as a fluorescent energy acceptor compound which is able to accept fluorescent energy from said donor compound; (b) exciting the fluorescent energy donor compound by illuminating with light of a wavelength which is absorbed by