Abstract: The invention relates to the field of immunology and immunodiagnostics. Provided is a method for determining the replicative history of a lymphocyte, preferably a B cell, the method comprising detecting a signal joint nucleotide sequence on an extrachromosomal circular excision product in the lymphocyte, wherein the excision product is deleted from a chromosome to give a chromosomal-coding joint nucleotide sequence, wherein the coding joint is retained in the chromosome, and detecting the coding joint nucleotide sequence in the lymphocyte. Also provided are primers, probes and a control cell for use in a method of the invention.

Abstract: The invention relates to the detection of, among others, tumor-specific fusion proteins. Provided is a method for detecting a fusion protein in a sample, the fusion protein comprising an amino-terminal fragment and a carboxy-terminal fragment that each correspond to a native protein. The method comprises contacting the sample with at least one binding molecule specifically reactive with a part of the native protein that is not present in the fusion protein, under conditions that allow for the formation of a complex between at least one binding molecule and the native protein, removing the complex from the sample to deplete the sample of the native protein but not of the fusion protein; and detecting the fusion protein in the sample using at least one antibody probe directed against the fusion protein. Also provided is a diagnostic kit for carrying out a method of the invention.

Abstract: A novel method for detecting chromosome aberrations is disclosed. More specifically, chromosome aberrations are detected by in situ hybridisation using at least two sets of hybridisation probes, at least one set comprising one or more peptide nucleic acid probes capable of hybridising to specific nucleic acid sequences related to a potential aberration in a chromosome, and at least one set comprising two or more peptide nucleic acid probes capable of hybridising to specific nucleic acid sequences related to another potential aberration in a chromosome. In particular, the method may be used for detecting chromosome aberrations in the form of breakpoints.

Abstract: The invention relates to the field of cytogenetics and the application of genetic diagnostic techniques in pathology and hematology. Specifically, the invention relates to nucleic acid probes that can be used in hybridization techniques for the detection of chromosomal aberrations and other gene rearrangements such as immunoglobulin and T-cell receptor gene rearrangements. The probes provided by the invention are a distinct and balanced set of probes of comparable size, each preferably being from 1 to 100 kb, or smaller, and flanking a potential breakpoint in a chromosome.

Abstract: This invention relates to the detection of fusion proteins. The invention provides a set of at least a first and a second molecular probe, each probe provided with a dye wherein the dyes together allow energy transfer, at least one probe provided with a reactive group allowing juxtaposing at least the first and second probes wherein the reactive group allows to modulate juxtaposing the probes such that there is an increased likelihood of energy transfer between the dyes. A method is provided which permits detecting the presence of a fusion protein in a cell at the single cell level.

Abstract: This invention relates to the field of detecting interacting molecules. The invention provides a set of a first and a second probe, each such probe provided with a dye allowing energy transfer; at least one probe provided with a reactive group allowing juxtaposing the first and second probe. A method is provided for detecting at least two interacting molecules at the single cell level using of a set of probes according to the invention.