Abstract: The present invention provides methods for the determination of the viral titer of a culture of host animal host cells infected with a circovirus. The FACS-based methods of the invention may include determining the viability of the host cells in a cell culture medium supernatant and of those cells that remain adherent to a solid support. Detecting and measuring the percentage of cells that expressed the viral antigens ORF1 and ORF2 may determine the viral load of the cultured host cells. The yield of the virus may be established by the detection and measurement of both antigens in supernatant cells, for example 5 to 7 days from when the host cells are transferred to a serum free medium. The methods of the invention may yield rapid quantitative data. This allows the repeated in-process monitoring of the viral production throughout the incubation period, and ready selection of the most appropriate harvesting point.

Abstract: The present invention provides methods for the determination of the viral titer of a culture of host animal host cells infected with a circovirus. The FACS-based methods of the invention may include determining the viability of the host cells in a cell culture medium supernatant and of those cells that remain adherent to a solid support. Detecting and measuring the percentage of cells that expressed the viral antigens ORF1 and ORF2 may determine the viral load of the cultured host cells. The yield of the virus may be established by the detection and measurement of both antigens in supernatant cells, for example 5 to 7 days from when the host cells are transferred to a serum free medium. The methods of the invention may yield rapid quantitative data. This allows the repeated in-process monitoring of the viral production throughout the incubation period, and ready selection of the most appropriate harvesting point.

Abstract: The present invention provides methods for the determination of the viral titer of a culture of host animal host cells infected with a circovirus. The FACS-based methods of the invention may include determining the viability of the host cells in a cell culture medium supernatant and of those cells that remain adherent to a solid support. Detecting and measuring the percentage of cells that expressed the viral antigens ORF1 and ORF2 may determine the viral load of the cultured host cells. The yield of the virus may be established by the detection and measurement of both antigens in supernatant cells, for example 5 to 7 days from when the host cells are transferred to a serum free medium. The methods of the invention may yield rapid quantitative data. This allows the repeated in-process monitoring of the viral production throughout the incubation period, and ready selection of the most appropriate harvesting point.

Abstract: The present invention provides methods for the determination of the viral titer of a culture of host animal host cells infected with a circovirus. The FACS-based methods of the invention may include determining the viability of the host cells in a cell culture medium supernatant and of those cells that remain adherent to a solid support. Detecting and measuring the percentage of cells that expressed the viral antigens ORF1 and ORF2 may determine the viral load of the cultured host cells. The yield of the virus may be established by the detection and measurement of both antigens in supernatant cells, for example 5 to 7 days from when the host cells are transferred to a serum free medium. The methods of the invention may yield rapid quantitative data. This allows the repeated in-process monitoring of the viral production throughout the incubation period, and ready selection of the most appropriate harvesting point.

Abstract: A procedure for detecting single-stranded nucleotide sequences in a sample is disclosed wherein a passively fixed capture probe is used in concert with a non-radioactively labelled detection probe in a sandwich hybridization technique.

Abstract: In a process for immobilization by passive fixation on a solid support of a nucleic acid fragment containing less than 100 nucleotides, the fragment is deposited on the support in the form of a derivative. The derivative results from the covalent coupling of the fragment with a ligand having a molecular mass of less than 5,000 and containing at least one polar functional group. The derivative is not capable of forming a covalent bond with the support under the conditions of the deposition. When the ligand is a nucleotide or an oligonucleotide it is at least one nucleotide modified so as to introduce the polar functional group.