Nucleic acid amplification controls
View Patent ↗The present invention discloses positive control material for nucleic acid amplification based detection of microorganisms in biological samples. The control material comprises purified microorganism that is rendered non-infectious but is amenable to nucleic acid amplification. Also disclosed is a process for making and using the control material.
1. A method for detection of a microorganism in a biological test sample comprising: a) providing a biological fluid test sample suspected of comprising the microorganism; b) providing a positive control sample comprising the microorganism in a biological fluid corresponding to the biological fluid of the test sample, wherein the positive control sample is prepared by exposing a purified microorganism to an aldehyde at a temperature of 2-8° C., and quenching the aldehyde exposed microorganism with glycine for at least 2 hours such that the microorganism is in an intact, non-pathogenic, form in which one or more of the surface proteins have been irreversibly modified by covalent attachment to the aldehyde and wherein the nuclear components are substantially intact; c) processing the test and the positive control sample to extract the nuclear components of the microorganisms; d) amplifying the nuclear components of the microorganisms in the test sample and the positive control; and e) comparing the results of nucleic acid amplification in the test sample and the positive control to identify the presence of microorganisms in the test sample.
2. The method of claim 1 , wherein the aldehyde comprises a single reactive functional group.
3. The method of claim 2 , wherein the aldehyde is selected from the group consisting of paraformaldehyde, formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, benzaldehyde, p-nitrobenzaldehyde, p-tolualdehyde, salicylaldehyde, phenylacetaldehyde.
4. The method of claim 1 , wherein the aldehyde comprises two or more reactive functional groups.
5. The method of claim 4 , wherein the aldehyde is paraformaldehyde.
6. The method of claim 1 , wherein the microorganism is a virus.
7. The method claim 6 , wherein the virus is chosen from the group consisting of human immunodeficiency virus, hepatitis C virus, hepatitis B virus, cytomegalovirus, human lymphotrophic virus, Epstein-Barr virus, parvovirus, herpes simplex virus, human herpes virus 8 and hepatitis A Virus.
8. The method of claim 1 , wherein the microorganism is an intracellular parasite.
9. The method of claim 8 , wherein the parasite is chosen from the group consisting of Chlamydia trachomatis, Chlamydia psittaci, Rickettsia prowazeki, Rickettsia typhi, Rickettsia rickettsi, Rickettsia sibtricus, Rickeitsia conori, Rickettsia australis, Rickettsia akari, Rickettsia tsutsugamushi, Coxiella bumeti and Rochalimaea Quintana.
10. The method of claim 1 , wherein the positive control is added to the test sample.
11. The method of claim 1 , wherein the biological fluid test sample is selected from the group consisting of serum, plasma, defibrinated plasma, stabilized plasma pool, cerebrospinal fluid, urine, saliva, semen and sputum.