Simultaneous diagnosis kit for a disease due to a respiratory virus

The content of the electronically submitted sequence listing (Name 2972.0030001_CorrectedSequenceListing_ascii; Size: 10KB bytes; and Date of Creation: Jan, 7, 2014) filed with the application is incorporated herein by reference in its entirety.

The present invention relates to a kit for simultaneous diagnosis of viral respiratory diseases. To be more specific, the present invention is directed to a method for diagnosing viral respiratory diseases by detecting the gene specific to the respiratory disease-causing virus, a primer set for diagnosing the viral respiratory diseases used in the diagnosis method, a composition for simultaneous diagnosis of viral respiratory diseases, comprising the primer set, and a kit for simultaneous diagnosis of viral respiratory diseases, comprising the composition.

A respiratory virus is the main cause of acute respiratory infection, which is regarded as the most common disease irrespective of age or gender. In particular, for infants, elders, or people with weak cardiopulmonary function and immunity, a respiratory infection may cause aftereffects, leading to death. Diseases associated with respiratory virus mostly start with cold symptoms and may cause other various symptoms such as pharyngitis, worsening of chronic asthma, and pneumonia. Early diagnosis of viral respiratory infection can prevent drug abuse of unnecessary antibiotics and identify a type of virus early, thereby allowing providing a suitable treatment to the patients.

Methods for detecting the respiratory virus include conventional culture, rapid cell culture, rapid antigen non-immunofluorescence tests, rapid antigen immunofluorescence based tests, and molecular methods that use electrophoresis. The cell culture, which is a standard test method, takes more than 5 to 9 days to get the test results, and thus it has limitations to be used for early diagnosis and treatment of viral respiratory infection. To resolve these limitations, a R-Mix viral culture, which gives the test results within 24 to 72 hours and has similar sensitivity to conventional culture, has been used, but this also has a limitation to be used for early diagnosis and treatment of the disease. Also, rapid antigen non-immunofluorescence test can give the test results fast, but has a disadvantage of yielding high false negative results, as it is less sensitive than the conventional culture. As for molecular methods that use electrophoresis, it has a good sensitivity, but has a risk of contamination since it is conducted in two steps, and also takes long time to perform.

With this background, in effort to develop a method for resolving the limitations of the detection method for respiratory virus, including low sensitivity, risk of contamination, and long performing time, the present inventors have developed the primer sets and probes that can amplify the genes that are specific to 14 types of viruses, and confirmed that when each of the primer set and probe is used, the 14 types of respiratory viruses can be diagnosed simultaneously with high sensitivity and specificity, thereby completing the present invention.

Technical Problem

One object of the present invention is to provide a method for diagnosing viral respiratory diseases by detecting the genes specific to the respiratory disease-causing virus.

Another object of the present invention is to provide a primer set for diagnosing the viral respiratory diseases used in the diagnosis method.

Another object of the present invention is to provide a composition for simultaneous diagnosis of viral respiratory diseases, comprising the primer set.

Another object of the present invention is to provide a kit for simultaneous diagnosis of viral respiratory diseases, comprising the composition.

Technical Solution

As one embodiment to achieve the above objectives, the present invention provides a primer comprising a nucleotide sequence selected from the group consisting of SEQ ID Nos. 1 to 14 and 17 to 33 for determining the infection of respiratory virus.

As used herein, the term “diagnosis” refers to the determination of pathologic status. For the purpose of the present invention, diagnosis means determining the onset of diseases caused by respiratory viruses and the prognosis of the therapeutic treatment with antiviral agents, by confirming the expression of the genes specific to various existing respiratory viruses.

As used herein, the term “primer” refers to a nucleotide sequence having a short free 3′ hydroxyl group, which can form a base pair with complementary template and function as a starting point for replicating template. A primer can initiate DNA synthesis in the presence of reagents for polymerization (e.g., DNA polymerase or reverse transcriptase) and four different deoxynucleoside triphospate (dNTP) in a suitable buffer and at an optimal temperature. According to the present invention, it is preferable that the primer consists of forward nucleotide sequence and reverse nucleotide sequence having 10 to 30 bases each.

The primer can amplify the gene specific to a respiratory virus through PCR for determining the infection of respiratory virus, and the respiratory virus includes, but is not particularly limited to, corona virus 229E, corona virus OC43, corona virus NL63, influenza A virus, influenza B virus, parainfluenza virus 1, parainfluenza virus 2, parainfluenza virus 3, respiratory syncytial virus A, respiratory syncytial virus B, adenovirus, rhino virus A, B, and C, metapneumovirus, and boca virus. The genes that can distinguish each of the respiratory virus from other viruses include, but is not particularly limited to, nucleoprotein (N) gene of corona virus 229E, nucleoprotein (N) gene of corona virus OC43, polyprotein (1a) gene of corona virus NL63, matrix protein (M) gene of influenza A virus, hemagglutinin (HA) gene of influenza B virus, hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 1, hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 2, hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 3, fusion protein gene of respiratory syncytial virus A, fusion protein gene of respiratory syncytial virus B, hexon protein gene of adenovirus, 5′UTR of rhino virus A, B, and C, nucleoprotein (N) gene of metapneumovirus, and nucleocapsid protein (NP) gene and viral protein (VP) gene of boca virus.

The primers provided in the present invention are preferably, but not particularly limited to, a primer having a nucleotide sequence of SEQ ID No. 1 or 2 capable of amplifying nucleoprotein (N) gene of corona virus 229E; a primer having a nucleotide sequence of SEQ ID No. 3 or 4 capable of amplifying nucleoprotein (N) gene of corona virus OC43; a primer having a nucleotide sequence of SEQ ID No. 5 or 6 capable of amplifying polyprotein (1a) gene of corona virus NL63; a primer having a nucleotide sequence of SEQ ID No. 7 or 8 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 1; a primer having a nucleotide sequence of SEQ ID No. 9 or 10 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 2; a primer having a nucleotide sequence of SEQ ID No. 11 or 12 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 3; a primer having a nucleotide sequence of SEQ ID No. 13 or 14 capable of amplifying matrix protein (M) gene of influenza A virus; a primer having a nucleotide sequence of SEQ ID No. 17 or 18 capable of amplifying hemagglutinin (HA) gene of influenza B virus; a primer having a nucleotide sequence of SEQ ID No. 19 or 20 capable of amplifying fusion protein gene of respiratory syncytial virus A; a primer having a nucleotide sequence of SEQ ID No. 21 or 22 capable of amplifying fusion protein gene of respiratory syncytial virus B; a primer having a nucleotide sequence of SEQ ID No. 25 or 26 capable of amplifying hexon protein gene of adenovirus; a primer having a nucleotide sequence of SEQ ID Nos. 27 to 31 capable of amplifying 5′UTR of rhino virus A, B, and C; a primer having a nucleotide sequence of SEQ ID No. 23 or 24 capable of amplifying nucleoprotein (N) gene of metapneumovirus; and a primer having a nucleotide sequence of SEQ ID No. 32 or 33 capable of amplifying nucleocapsid protein (NP) gene of boca virus. Also, the primer may comprise additional features as long as the basic function thereof acting as a starting point for DNA synthesis is not changed.

In addition, the nucleotide sequence of the primer of the present invention may comprise a marker, which is directly or indirectly detectable through spectroscopic method, photochemical method, biochemical method, immunochemical method, or chemical method, if necessary. Examples of the marker include enzyme (e.g., horseradish peroxidase and alkaline phosphatase), radioactive isotope (e.g., 32P), fluorescent molecule, and chemical groups (e.g., biotin).

Furthermore, the primer may be chemically synthesized by using phosphoramidite solid support or other methods widely known in the art. The nucleotide sequence of such primers can be modified by using various methods in the art, and preferably by methylation, capsulation, substitution of more than one native nucleotides by homologues, and addition of various linkers (e.g., methyl phosphonate, phosphotriester, phosphoramidite, carbamate, phosphorothioate, and phosphorodithioate), but is not limited thereto.

As another aspect to achieve the above objectives, the present invention provides a composition for simultaneous diagnosis of respiratory virus, comprising the primer set.

The composition for simultaneous diagnosis of respiratory virus of the present invention comprises a primer having a nucleotide sequence of SEQ ID No. 1 or 2 capable of amplifying nucleoprotein (N) gene of corona virus 229E; a primer having a nucleotide sequence of SEQ ID No. 3 or 4 capable of amplifying nucleoprotein (N) gene of corona virus OC43; a primer having a nucleotide sequence of SEQ ID No. 5 or 6 capable of amplifying polyprotein (1a) gene of corona virus NL63; a primer having a nucleotide sequence of SEQ ID Nos. 7 and 8 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 1; a primer having a nucleotide sequence of SEQ ID Nos. 9 and 10 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 2; a primer having a nucleotide sequence of SEQ ID Nos. 11 and 12 capable of amplifying hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 3; a primer having a nucleotide sequence of SEQ ID Nos. 13 and 14 capable of amplifying matrix protein (M) gene of influenza A virus; a primer having a nucleotide sequence of SEQ ID Nos. 17 and 18 capable of amplifying hemagglutinin (HA) gene of influenza B virus; a primer having a nucleotide sequence of SEQ ID Nos. 19 and 20 capable of amplifying fusion protein gene of respiratory syncytial virus A; a primer having a nucleotide sequence of SEQ ID Nos. 21 and 22 capable of amplifying fusion protein gene of respiratory syncytial virus B; a primer having a nucleotide sequence of SEQ ID Nos. 25 and 26 capable of amplifying hexon protein gene of adenovirus; a primer having a nucleotide sequence of SEQ ID Nos. 27 to 31 capable of amplifying 5′UTR of rhino virus A, B, and C; a primer having a nucleotide sequence of SEQ ID Nos. 23 and 24 capable of amplifying nucleoprotein (N) gene of metapneumovirus; and a primer having a nucleotide sequence of SEQ ID Nos. 32 and 33 capable of amplifying nucleocapsid protein (NP) gene of boca virus. Preferably, the composition of the present invention comprises two or more primer sets consisting of the above-listed primer sets, and can be used for diagnosing two or more respiratory viruses simultaneously.

The composition may further comprise the probes having a nucleotide sequence selected from the group consisting of SEQ ID Nos. 34 to 40 and 42 to 52, for detecting respiratory virus-specific genes more efficiently.

As used herein, the term “probe” refers to a nucleotide fragment of RNA or DNA that is composed of several bases to several hundreds of bases, and that can bind specifically to a complementary nucleotide sequence. Since the probes are labeled, it can be used for detecting the presence of certain nucleotide sequences. Probes may be prepared in the form of oligonucleotide probe, single stranded DNA probe, double stranded DNA probe, and RNA probe. Also, for performing real-time PCR, a fluorescence-labeled probe may be used. More specifically, as for TaqMan probe, an oligonucleotide, whose 5′ terminal is modified with fluorescent molecule and the 3′ terminal is modified with quencher, is added to a PCR reaction. Also, the real-time PCR using cycling probe is a highly sensitive detection method, consisting of a chimeric probe composed of RNA, DNA and RNase H. For this method, 5′ terminal of probe is labeled with fluorescent molecule and 3′ terminal is labeled with quencher.

When real-time PCR is employed to detect the amplified product, the amplification of the product can be monitored in real time, and thus DNA and RNA can be quantified accurately, analyzed promptly and easily as electrophoresis is not required, and also there is low risk of contamination. Based on these facts, the present inventors have prepared a fluorescence-labeled probe for diagnosing respiratory virus more efficiently by employing real-time PCR. It is preferable to use a probe having a nucleotide sequence of SEQ ID No. 34 capable of detecting nucleoprotein (N) gene of corona virus 229E; a probe having a nucleotide sequence of SEQ ID No. 35 capable of detecting nucleoprotein (N) gene of corona virus OC43; a probe having a nucleotide sequence of SEQ ID No. 36 capable of detecting polyprotein (1a) gene of corona virus NL63; a probe having a nucleotide sequence of SEQ ID No. 37 capable of detecting hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 1; a probe having a nucleotide sequence of SEQ ID No. 38 capable of detecting hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 2; a probe having a nucleotide sequence of SEQ ID No. 39 capable of detecting hemagglutinin-neuraminidase (HN) gene of parainfluenza virus 3; a probe having a nucleotide sequence of SEQ ID No. 40 capable of detecting matrix protein (M) gene of influenza A virus; a probe having a nucleotide sequence of SEQ ID No. 42 capable of detecting hemagglutinin (HA) gene of influenza B virus; a probe having a nucleotide sequence of SEQ ID No. 43 capable of detecting fusion protein gene of respiratory syncytial virus A; a probe having a nucleotide sequence of SEQ ID No. 44 capable of detecting fusion protein gene of respiratory syncytial virus B; a probe having a nucleotide sequence of SEQ ID No. 45 capable of detecting nucleoprotein (N) gene of metapneumovirus; a probe having a nucleotide sequence of SEQ ID Nos. 46 to 49 capable of detecting hexon protein gene of adenovirus; a probe having a nucleotide sequence of SEQ ID Nos. 50 and 51 capable of detecting 5′UTR of rhino virus A, B, and C; and a probe having a nucleotide sequence of SEQ ID No. 52 capable of detecting nucleocapsid protein (NP) gene and viral protein (VP) gene of boca virus, but is not particularly limited thereto.

Also, in order to provide a standard for determining validity of RNA extraction, a primer having a nucleotide sequence of SEQ ID Nos. 15 and 16 as a human RNase P-targeting internal control primer or a probe having a nucleotide sequence of SEQ ID No. 41 may be further added to the composition.

Furthermore, as similar to the primers, the probes provided in the present invention may be chemically synthesized by using phosphoramidite solid support or other methods widely known in the art. The nucleotide sequence of such probes can be modified by using various methods in the art, and preferably by methylation, capsulation, substitution of more than one native nucleotides by homologues, and addition of various linkers (e.g., methyl phosphonate, phosphotriester, phosphoramidite, carbamate, phosphorothioate, and phosphorodithioate), but is not limited thereto.

The composition for diagnosing respiratory virus of the present invention may further comprise a DNA polymerase for performing PCR in addition to the probes, and the DNA polymerase is preferably a hot start Taq DNA polymerase, but is not particularly limited thereto.

Also, the composition for diagnosing respiratory virus of the present invention may use the RNA extracted from the sample as a target sample. To use RNA as a sample, reverse transcriptase (RT)-PCR needs to be performed additionally, and it also needs to be confirmed whether the respiratory virus-specific gene is present in the PCR product. Thus the composition may further comprise a reverse transcriptase for performing RT-PCR, in addition to the probes and DNA polymerase.

As another aspect to achieve the above objectives, the present invention provides a kit for simultaneous diagnosis of respiratory viruses, comprising the primer set or the composition.

The kit for simultaneous diagnosis of respiratory viruses of the present invention comprises two or more or the primer sets or the composition as similar to the above-described composition for diagnosing respiratory viruses, and thus can be used for simultaneous diagnosis of two or more of the respiratory viruses.

Also, the kit of the present invention may further comprise one or more types of compositions, solutions, or devices having different constituents that are suitable for the purposes of analysis. For instance, the kit for diagnosis of the present invention may be a kit for simultaneous diagnosis of respiratory viruses that further comprises a reverse transcriptase, which is a required constituent for performing RT-PCR and multiplex real-time PCR and for synthesizing a complementary DNA (cDNA) of RNA, i.e., respiratory virus gene, in addition to the primer set specific to a target gene; a DNA polymerase for amplifying cDNA; a tube or other suitable container; a reaction buffer (with various pH levels and magnesium concentration); deoxynucleotides (dNTPs); enzymes such as hot start Taq-polymerase and reverse transcriptase; DNase and RNase inhibitors; DEPC-water; and sterilized water, but is not limited thereto.

As another aspect to achieve the above objectives, the present invention provides a method for diagnosing viral respiratory diseases by using the composition or the kit, or a method for providing the information for diagnosing viral respiratory diseases.

To be more specific, the method for diagnosing viral respiratory diseases of the present invention comprises (i) preparing a reaction mixture by mixing the primer, the probe, a DNA polymerase and a reverse transcriptase; (ii) obtaining a reaction product by adding DNA or RNA from a sample to the reaction mixture and successively performing Reverse transcription-PCR and real-time PCR; and (iii) detecting 1 to 14 types of the disease-causing viruses simultaneously by analyzing the reaction product. The respiratory viruses preferably include, but are not limited to, corona virus 229E, corona virus OC43, corona virus NL63, influenza A virus, influenza B virus, parainfluenza virus 1, parainfluenza virus 2, parainfluenza virus 3, respiratory syncytial virus A, respiratory syncytial virus B, adenovirus, rhino virus A, B, and C, metapneumovirus, and boca virus.

As used herein, the term “sample” refers to the samples such as saliva and sputum (e.g., nasopharyngeal swabs (NPS), nasal swabs (NS), throat swabs (TS), and nasal aspirates (NA)), wherein the expression level of the genes specific to each of the viruses changes by the infection of various respiratory viruses, but is not limited thereto.

Advantageous Effects

When the primer set of the present invention for diagnosing the viral respiratory diseases is used, 14 different types of respiratory viruses can be simultaneously detected only with one reaction through real-time multiplex reverse transcription (RT)-PCR, and the onset of respiratory diseases caused by these viruses can be diagnosed. Thus, the primer set of the present invention can be widely used for prompt diagnosis and treatment of respiratory diseases.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these Examples are for illustrative purposes only, and the invention is not intended to be limited by these Examples.