Response to „No evidence of SARS-CoV-2 infection by PCR or serology in children with pseudochilblain”
We read with interest the article by Caselli D et al., reporting a case series of 38 children with chilblain-like lesions (CLL). Testing for SARS-CoV-2, including PCR, rapid test serology and ELISA method for IgA and IgG antibodies yielded negative results in all cases. They concluded that their data do not allow them to support the relationship of CLL with SARS-CoV-2 infection. So far, data in the literature studying CLL documented a very low percentage of laboratory confirmed SARS-CoV-2. However, Colmenero and colleagues were able to detect SARS-CoV-2 in endothelial cells of cutaneous chilblain lesions by immunohistochemistry methods in 7 pediatric patients with negative nasopharyngeal swabs.
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A wide range of well-characterized bioactive molecules that covers various targets related to GPCR, including adenosine receptor, adrenergic receptor and CXCR etc. Facilitate your research towards the insights of cancer, neurological disorders and heart diseases etc.
Complement C4 Gene Copy Number Variation Genotyping by High Resolution Melting PCR
Background: Complement C4 gene copy number variation plays an important role as a determinant of genetic susceptibility to common diseases, such as systemic lupus erythematosus, schizophrenia, rheumatoid arthritis, and infectious diseases. This study aimed to develop an assay for the quantification of copy number variations in the C4 locus.
Methods: the assay was based on a gene ratio analysis copy enumeration (GRACE) PCR combined with high resolution melting (HRM) PCR. The test was optimized using samples of a known genotype and validated with 72 DNA samples from healthy blood donors.
Results: to validate the assay, standard curves were generated by plotting the C4/RP1 ratio values against copy number variation (CNV) for each gene, using genomic DNA with known C4 CNV. The range of copy numbers in control individuals was comparable to distributions observed in previous studies of European descent.
Conclusions: the method herein described significantly simplifies C4 CNV diagnosis to validate the assay.
Detection of BRAF V600E Mutation in Ganglioglioma and Pilocytic Astrocytoma by Immunohistochemistry and Real-Time PCR-Based Idylla Test
The BRAF V600E mutation is an important oncological target in certain central nervous system (CNS) tumors, for which a possible application of BRAF-targeted therapy grows continuously. In the present study, we aim to determine the prevalence of BRAF V600E mutations in a series of ganglioglioma (GG) and pilocytic astrocytoma (PA) cases. Simultaneously, we decided to verify whether the combination of fully automated tests-BRAF-VE1 immunohistochemistry (IHC) and Idylla BRAF mutation assay-may be useful to accurately predict it in the case of specified CNS tumors.
The study included 49 formalin-fixed, paraffin-embedded tissues, of which 15 were GG and 34 PA. Immunohistochemistry with anti-BRAF V600E (VE1) antibody was performed on tissue sections using the VentanaBenchMark ULTRA platform. All positive or equivocal cases on IHC and selected negative ones were further assessed using the Idylla BRAF mutation assay coupled with the Idylla platform. The BRAF-VE1 IHC was positive in 6 (6/49; 12.3%) and negative in 39 samples (39/49; 79.6%). The interpretation of immunostaining results was complicated in 4 cases, of which 1 tested positive for the Idylla BRAF mutation assay. Therefore, the overall positivity rate was 14.3%. This included 2 cases of GG and 5 cases of PA. Our study found that BRAF V600E mutations are moderately frequent in PA and GG and that for these tumor entities, IHC VE1 is suitable for screening purposes, but all negative, equivocal, and weak positive cases should be further tested with molecular biology techniques, of which the Idylla system seems to be a promising tool.
Establishment of an SYBR Green-based real-time PCR assay for porcine circovirus type 4 detection
Porcine circovirus 4 (PCV4) is a novel circovirus first discovered in China in April 2019. Here, we established an SYBR Green I-based real-time PCR for quantitative detection of PCV4. A pair of specific primers was designed based on the conserved region of Cap of PCV4. The standard curve of the established real-time PCR assay showed a good linear relationship.
The sensitivity of the established real-time PCR was 100 times greater than that of conventional PCR, and the detection limit of the assay was 3 × 101 copies. There was no cross-reactivity with other swine DNA viruses, showing good specificity. The intra-group variation coefficient was 0.37-0.78%, and the inter-group variation coefficient was 0.57-0.94%, indicating that the assay has good repeatability. Moreover, the analysis of clinical samples showed that the positive detection rate of PCV4 was 10.71% (18/168), while that of conventional PCR was 8.93% (15/168). Interestingly, co-infection with PCV2 or PCV3, or both PCV2 and PCV3, was also detected. In conclusion, the established SYBR Green I-based real-time PCR may be a cost-effective and rapid method for PCV4 clinical diagnosis.
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A wide range of well-characterized bioactive molecules that covers various targets related to GPCR, including adenosine receptor, adrenergic receptor and CXCR etc. Facilitate your research towards the insights of cancer, neurological disorders and heart diseases etc.
Complement C4 Gene Copy Number Variation Genotyping by High Resolution Melting PCR
Background: Complement C4 gene copy number variation plays an important role as a determinant of genetic susceptibility to common diseases, such as systemic lupus erythematosus, schizophrenia, rheumatoid arthritis, and infectious diseases. This study aimed to develop an assay for the quantification of copy number variations in the C4 locus.
Methods: the assay was based on a gene ratio analysis copy enumeration (GRACE) PCR combined with high resolution melting (HRM) PCR. The test was optimized using samples of a known genotype and validated with 72 DNA samples from healthy blood donors.
Results: to validate the assay, standard curves were generated by plotting the C4/RP1 ratio values against copy number variation (CNV) for each gene, using genomic DNA with known C4 CNV. The range of copy numbers in control individuals was comparable to distributions observed in previous studies of European descent.
Conclusions: the method herein described significantly simplifies C4 CNV diagnosis to validate the assay.
Detection of BRAF V600E Mutation in Ganglioglioma and Pilocytic Astrocytoma by Immunohistochemistry and Real-Time PCR-Based Idylla Test
The BRAF V600E mutation is an important oncological target in certain central nervous system (CNS) tumors, for which a possible application of BRAF-targeted therapy grows continuously. In the present study, we aim to determine the prevalence of BRAF V600E mutations in a series of ganglioglioma (GG) and pilocytic astrocytoma (PA) cases. Simultaneously, we decided to verify whether the combination of fully automated tests-BRAF-VE1 immunohistochemistry (IHC) and Idylla BRAF mutation assay-may be useful to accurately predict it in the case of specified CNS tumors.
The study included 49 formalin-fixed, paraffin-embedded tissues, of which 15 were GG and 34 PA. Immunohistochemistry with anti-BRAF V600E (VE1) antibody was performed on tissue sections using the VentanaBenchMark ULTRA platform. All positive or equivocal cases on IHC and selected negative ones were further assessed using the Idylla BRAF mutation assay coupled with the Idylla platform. The BRAF-VE1 IHC was positive in 6 (6/49; 12.3%) and negative in 39 samples (39/49; 79.6%). The interpretation of immunostaining results was complicated in 4 cases, of which 1 tested positive for the Idylla BRAF mutation assay. Therefore, the overall positivity rate was 14.3%. This included 2 cases of GG and 5 cases of PA. Our study found that BRAF V600E mutations are moderately frequent in PA and GG and that for these tumor entities, IHC VE1 is suitable for screening purposes, but all negative, equivocal, and weak positive cases should be further tested with molecular biology techniques, of which the Idylla system seems to be a promising tool.
Establishment of an SYBR Green-based real-time PCR assay for porcine circovirus type 4 detection
Porcine circovirus 4 (PCV4) is a novel circovirus first discovered in China in April 2019. Here, we established an SYBR Green I-based real-time PCR for quantitative detection of PCV4. A pair of specific primers was designed based on the conserved region of Cap of PCV4. The standard curve of the established real-time PCR assay showed a good linear relationship. The sensitivity of the established real-time PCR was 100 times greater than that of conventional PCR, and the detection limit of the assay was 3 × 101 copies. There was no cross-reactivity with other swine DNA viruses, showing good specificity. The intra-group variation coefficient was 0.37-0.78%, and the inter-group variation coefficient was 0.57-0.94%, indicating that the assay has good repeatability. Moreover, the analysis of clinical samples showed that the positive detection rate of PCV4 was 10.71% (18/168), while that of conventional PCR was 8.93% (15/168). Interestingly, co-infection with PCV2 or PCV3, or both PCV2 and PCV3, was also detected. In conclusion, the established SYBR Green I-based real-time PCR may be a cost-effective and rapid method for PCV4 clinical diagnosis.
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A polyclonal antibody for detection of D-GPCR from Human. This D-GPCR antibody is for WB, IF, ELISA. It is affinity-purified from rabbit antiserum by affinity-chromatography using epitope-specific immunogenand is unconjugated. The antibody is produced in rabbit by using as an immunogen synthesized peptide derived from the C-terminal region of human D-GPCR at AA range: 210-290
Description: A wide range of well-characterized bioactive molecules that covers various targets related to GPCR, including adenosine receptor, adrenergic receptor and CXCR etc. Facilitate your research towards the insights of cancer, neurological disorders and heart diseases etc.
