Abstract: Methods and compositions for detecting the presence, e.g., quantitatively, of a target nucleic acid, such as an siRNA, in a sample are provided. In the subject methods, a sample is contacted with at least two different ligation domains, which may be present on separate nucleic acids (e.g., oligonucleotides) or on the same complex, e.g., Combined Oligo, to produce a reaction mixture, where each of the different ligation domains includes a domain complementary to a different region of the target nucleic acid. The ligation domains of any resultant ligation domain/target nucleic acid complexes are then ligated to produce a pseudotarget nucleic acid. The presence of any resultant pseudotarget nucleic acids in the reaction mixture is then determined in order to detect the target nucleic acid in the sample. Also provided are systems and kits that find use in practicing the subject methods. The subject invention finds use in a variety of applications, including therapeutic applications.

Abstract: A method for expressing proteins which are immunologically reactive with antibodies to lymphadenopathy-associated virus (LAV), now known as Human Immunodeficiency Virus (HIV), is disclosed. The proteins are produced by bacterial host cells transformed with a recombinant plasmid which includes appropriate procaryotic transcriptional and translational signals for expression, followed in reading phase by a DNA sequence comprising a portion of the env region of the LAV genome. This portion codes for a protein which is immunologically reactive with antibodies to LAV, or antibodies to viruses defined to be the same as or equivalent to LAV. The proteins produced by the method disclosed may be used to screen for the presence of antibodies to LAV in a biological fluid, to determine the presence of LAV antigen in a biological fluid, or within a method for producing antibodies to LAV through the immunization of an animal with the protein.

Abstract: A method of expressing peptides which are immunologically reactive with antibodies to LAV is disclosed. The peptides are produced by bacterial host cells transformed with a recombinant plasmid which includes appropriate procaryotic transcriptional and translational signals for expression, followed by a DNA sequence coding for a peptide comprising the amino acid sequence as shown in FIG. 5 starting with isoleucine, number 1, and ending with threonine, number 173. The peptides of the present invention are immunologically reactive with antibodies to LAV, or antibodies to viruses defined to be the same as or equivalent to LAV. The peptides produced by the method disclosed may be used to screen for the presence of antibodies to LAV in a biological fluid, to determine the presence of LAV antigen in a biological fluid, or within a method for producing antibodies to LAV through the immunization of an animal with the peptide.