Polymorphism in the IL-1β promoter is associated with IgG antibody response to circumsporozoite protein repeats of Plasmodium vivax

Abstract Background It is well established that infection by Plasmodium vivax is a result of host-parasite interactions. In the present study, association with the IL1/IL2 cytokine profiles, anticircumsporozoite protein antibody levels and parasitic loads was evaluated in individuals naturally infected with P. vivax in an endemic area of the Brazilian Amazon. Methods Molecular diagnosis of P. vivax and variants was performed using the PCR-RFLP method and IL1B -511C>T, IL2 -330T>G and IL2+114T>G polymorphisms were identified using PCR-RFLP and allele-specific PCR. IL-1β and IL-2 cytokine levels were detected by flow cytometry and circumsporozoite protein (CSP) antibodies were measured by ELISA. Results Three variants of P. vivax CSP were identified and VK247 was found to be the most frequent. However, the prevalence and magnitude of IgG antibodies were higher for the VK210 variant. Furthermore, the antibody response to the CSP variants was not associated with the presence of the variant in the infection. Significant differences were observed between the single nucleotide polymorphism (SNP) -511T>C in the IL1B gene and levels of antibodies to the VK247 and P. vivax-like variants, but there were no associations between SNPs in IL1 and IL2 genes and their plasma products. Conclusions Individuals with the rs16944 CC genotype in the IL1β gene have higher antibody levels to the CSP of P. vivax of VK247 and P. vivax-like variants.

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Simple and Rapid Detection of Factor V Leiden by Allele-specific PCR Amplification

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650362 ◽

1996 ◽

Vol 75 (05) ◽

pp. 757-759 ◽

Cited By ~ 11

Author(s):

Rainer Blasczyk ◽

Markus Ritter ◽

Christian Thiede ◽

Jenny Wehling ◽

Günter Hintz ◽

...

Keyword(s):

Direct Sequencing ◽

Activated Protein C ◽

Factor V Leiden ◽

Pcr Amplification ◽

Factor V ◽

Specific Pcr ◽

Pcr Rflp ◽

Allele Specific ◽

Specific Amplification ◽

Allele Specific Pcr

SummaryResistance to activated protein C is the most common hereditary cause for thrombosis and significantly linked to factor V Leiden. In this study, primers were designed to identify the factor V mutation by allele-specific PCR amplification. 126 patients with thromboembolic events were analysed using this technique, PCR-RFLP and direct sequencing. The concordance between these techniques was 100%. In 27 patients a heterozygous factor VGln506 mutation was detected, whereas one patient with recurrent thromboembolism was homozygous for the point mutation. Due to its time- and cost-saving features allele-specific amplification should be considered for screening of factor VGln506.

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Multiple Antigenic Peptide-Based Vaccines Targeting Ixodes ricinus Neuropeptides Induce a Specific Antibody Response but Do Not Impact Tick Infestation

Pathogens ◽

10.3390/pathogens9110900 ◽

2020 ◽

Vol 9 (11) ◽

pp. 900

Author(s):

Consuelo Almazán ◽

Ladislav Šimo ◽

Lisa Fourniol ◽

Sabine Rakotobe ◽

Jérémie Borneres ◽

...

Keyword(s):

Antibody Response ◽

Ixodes Ricinus ◽

Antigenic Peptide ◽

Tick Feeding ◽

Igg Antibody ◽

Individual Level ◽

Multiple Antigenic Peptide ◽

New Strategy ◽

The Individual ◽

Antibody Levels

Synthetic peptide vaccines were designed to target the neuropeptides innervating Ixodes ricinus salivary glands and hindgut and they were tested for their capacity to afford protective immunity against nymphs or larvae and Anaplasma phagocytophilum-infected nymph infestation, in mice and sheep, respectively. In both models, the assembly of SIFamide (SIFa) or myoinhibitory peptide (MIP) neuropeptides into multiple antigenic peptide constructs (MAPs) elicited a robust IgG antibody response following immunization. Nevertheless, no observable detrimental impact on nymphs was evidenced in mice, and, unfortunately, the number of engorged nymphs on sheep was insufficient for firm conclusions to be drawn, including for bacterial transmission. Regarding larvae, while vaccination of the sheep did not globally diminish tick feeding success or development, analyses of animals at the individual level revealed a negative correlation between anti-SIFa and MIP antibody levels and larva-to-nymph molting success for both antigens. Our results provide a proof of principle and precedent for the use of MAPs for the induction of immunity against tick peptide molecules. Although the present study did not provide the expected level of protection, it inaugurates a new strategy for protection against ticks based on the immunological targeting of key components of their nervous system.

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Immunologic Response to Pneumococcal Polysaccharide Vaccine in Infants

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894800890s382 ◽

1980 ◽

Vol 89 (3_suppl) ◽

pp. 351-356 ◽

Cited By ~ 8

Author(s):

John L. Sloyer ◽

Laurel J. Karr ◽

John H. Ploussard ◽

Gerald D. Schiffman

Keyword(s):

Antibody Response ◽

Otitis Media ◽

Natural Infection ◽

Young Infant ◽

Serum Antibody ◽

Capsular Polysaccharides ◽

Igg Antibody ◽

Nasopharyngeal Colonization ◽

Antibody Levels ◽

Group 1

The serum antibody response to purified pneumococcal capsular polysaccharides (PCP) was determined in four groups of infants ranging in age from 3 to 24 months. Group 1 consisted of eight infants immunized with an octavalent vaccine containing serotypes 1, 3, 6, 7, 14, 18, 19 and 23 (PCP-8). Group 1 received 25 μg of each serotype at 3–6 months of age and again at 18–24 months. The antibody response after the second immunization was compared to a group of nine patients receiving a primary immunization at 18–24 months and to a group of ten age-matched controls receiving saline placebo. There were no significant differences in mean serum antibody levels between the two groups receiving the PCP-8. A fourth group of 44 infants between 6 and 21 months of age received either PCP-7 or PCP-8 and were followed for two years, at which time simultaneous injections of both vaccines were administered. Types 2, 3, 7, and 8 were most immunogenic but levels six months after immunization were approximately the same as for unimmunized controls with the exception of serotypes 3 and 7 which persisted for about two years. The class of antibody induced either by natural infection or by immunization was preferentially IgG and it was more often induced by the former. There were no significant differences between the serotypes of pneumococci isolated from nasopharyngeal cultures regardless of which vaccine was administered. Finally, the least immunogenic serotypes include 4, 6, 14, 19, and 23 and these are the only serotypes thus far associated with otitis media after immunization. The results suggest that PCP do not induce a lasting immune tolerance at the dose administered in this study; PCP are not very immunogenic in the young infant; PCP antibody tends to rise naturally; IgG antibody is preferentially induced; nasopharyngeal colonization is not altered by PCP immunization; and an association may exist between PCP immunogenicity and subsequent onset of otitis media.

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Heterozygosity for the Non-Deletional O2 Allele Does Not Cause Discrepancies in Automated Blood Donor ABO Grouping.

Blood ◽

10.1182/blood.v108.11.957.957 ◽

2006 ◽

Vol 108 (11) ◽

pp. 957-957 ◽

Cited By ~ 1

Author(s):

Mark H. Yazer ◽

Jonathan McGuirt ◽

Åsa Hellberg ◽

Bahram Hosseini-Maaf ◽

Annika Hult ◽

...

Keyword(s):

B Cells ◽

Consensus Sequence ◽

Flow Cytometric Analysis ◽

Antigen Expression ◽

Blood Group System ◽

Specific Pcr ◽

Pcr Rflp ◽

Digestion Pattern ◽

Allele Specific ◽

Group B

Abstract In the ABO blood group system any allele which does not give rise to A or B antigen expression is an O allele. The most common O alleles, O1 (O01) and O1v (O02) encode enzymatically inactive truncated proteins due to a single nucleotide polymorphism (SNP) compared to the consensus A1 allele, 261delG. Other O alleles containing the consensus nucleotide at residue 261 have been identified. The most common of these non-deletional O alleles is O2 (O03). It contains other SNPs which render the resulting protein non-functional. The most significant SNP is 802G>A (G268R); the arginine residue blocks the donor sugar’s access to the active site preventing its transfer. Recently O2 alleles were proposed to be the most common cause of ABO discrepancies (anti-A lacking or weakened in plasma despite apparent group O phenotype) in automated blood grouping (Transfusion2005;45:1331). Other clinical or biochemical reports have suggested that O2 may produce small amounts of A antigen on the RBC surface (Transfusion2005;45:70, 2005;45:359, J Biol Chem2005;280:525). To establish the effect of the O2 allele on automated ABO typing we extracted DNA from 562 randomly selected group O RBC units that were available for transfusion. Automated forward and reverse ABO grouping was performed on an Olympus PK7231 using A1 and B cells for reverse typing (Pittsburgh) and the IBG Multisampler Plato 3000 SI system using A1, A2 and B cells (Lund). A PCR-RFLP assay (Vox Sang 1995;69:242) involving amplification of exon 6 of the ABO gene followed by cleavage with KpnI to detect the presence of the 261delG SNP was performed and 34/562 (6%) of these units were heterozygous for a deletional and a non-deletional O allele. All 34 of these donors demonstrated an identical digestion pattern with BstEII which cleaves exon 6 in the presence of the consensus sequence at residue 261, confirming their heterozygosity for a non-deletional O allele. Allele-specific PCR to detect the O2-specific 802G>A polymorphism was performed on 32 of these donors for which additional DNA was available; the O2 allele was uniformly detected along with either an O1 or O1v allele. No homozygous O2O2 donors were identified. A sensitive flow cytometric analysis of the RBCs from 7 donors with the O2 allele was performed using monoclonal anti-A (ES-15) and a PE-labelled rat-anti-mouse kappa Ig secondary antibody. None of these RBCs demonstrated fluorescence levels in significant excess of the control O (O1O1) cells whilst A antigen on group B cells was demonstrable. Manual immediate spin and gel card forward typing was performed on these donors using a variety of murine monoclonal, polyclonal and experimental anti-A reagents; no A antigen was detected on their RBCs. Adsorption-elution studies were performed on the RBCs of 3 donors heterozygous for O2 using human-source polyclonal anti-A but no A antigen was detected. All 34 group O RBC units were transfused to group O recipients without reported hemolytic reactions. Our results suggest that in its heterozygous state the O2 allele does not necessarily induce ABO discrepancies in automated testing. Transfusing group O RBCs from donors with an O2 allele to recipients with anti-A did not result in reports of symptoms associated with hemolytic events in the recipients.

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Comparison of PCR-RFLP with Allele-Specific PCR in Genetic Testing for Spinal Muscular Atrophy

Genetic Testing ◽

10.1089/109065703322783626 ◽

2003 ◽

Vol 7 (4) ◽

pp. 277-281 ◽

Cited By ~ 10

Author(s):

Ruliang Xu ◽

Shuji Ogino ◽

Va Lip ◽

Hong Fang ◽

Bai-Lin Wu

Keyword(s):

Genetic Testing ◽

Spinal Muscular Atrophy ◽

Muscular Atrophy ◽

Specific Pcr ◽

Pcr Rflp ◽

Allele Specific ◽

Allele Specific Pcr

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Molecular Study of Benzimidazole Resistance in Teladorsagia circumcincta Isolated from Sheep in North of Iran

Iranian Journal of Parasitology ◽

10.18502/ijpa.v14i4.2108 ◽

2019 ◽

Author(s):

Rahim NEMATI ◽

Aliasghar BAHARI ◽

Pezhman MAHMOODI ◽

Alireza SAZMAND

Keyword(s):

Anthelmintic Resistance ◽

Molecular Study ◽

Nucleotide Polymorphisms ◽

Northern Iran ◽

The North ◽

Specific Pcr ◽

Teladorsagia Circumcincta ◽

Pcr Rflp ◽

North Of Iran ◽

Allele Specific

Background: Resistance to benzimidazole (BZ) compounds is common in Teladorsagia circumcincta populations in sheep and goats worldwide. Given the importance of anthelmintic resistance and shortage of information on single nucleotide polymorphisms (SNPs) in this prevalent nematode in Iran, this study was conducted. Methods: From June to September 2016, abomasa of 139 sheep of different sexes and ages in Amol City slaughterhouse, northern Iran were examined for isolation of nematodes. Totally 45 male T. circumcincta confirmed by both microscopical and nested-PCR-RFLP methods were included in this study. Susceptibility or resistance of each single T. circumcincta worm to benzimidazoles was assessed using allele-specific PCR. Results: Frequency of genotypes in the present study were 33.33% heterozygote BZ and 66.67% BZ homozygote sensitive. No homozygote resistant worm was found. Conclusion: Resistance against BZs in T. circumcincta of sheep has occurred at a low prevalence in the north of Iran. However, mutated genes might get dominant under drug selection in future. Hence, periodic investigations for early detection of mutated alleles in nematode populations using accurate and sensitive molecular methods such as PCR-RFLP is recommended.

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The Correlation Between IgM and IgG Antibodies With Blood Profile In Patients Infected With COVID 19

10.21203/rs.3.rs-572748/v1 ◽

2021 ◽

Author(s):

Zahra Alibolandi ◽

Amirreza Ostadian ◽

Saeed Sayyah ◽

Hamed Haddad Kashani ◽

Hassan Ehteram ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Antibody Response ◽

Laboratory Data ◽

Severe Illness ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Igg Antibody ◽

Blood Profile ◽

Virus Exposure ◽

Antibody Levels

Abstract Objectives: This study aimed to determine the levels of IgM and IgG antibody response to the severe acute respiratory syndrome coronavirus (SARS-CoV)-2 in coronavirus disease 2019 (COVID-19) patients with different disease severity.Methods: IgM and IgG antibody levels were evaluated via enzyme-linked immunosorbent assay (ELISA). In total, 100 patients with confirmed SARS-CoV-2 infection were enrolled in this study and viral RNA was detected by using Real-time PCR technique. Clinical and laboratory data were collected and analyzed after hospital admission for COVID-19 and two months post-admission. Results: The level of anti-SARS-CoV-2 antibody IgG was significantly higher in the severe patients than those in moderate and mild groups, 2 months after admission. Also, level of IgG was positively associated with increased WBC, NUT and LYM counts in sever than mild or moderate groups after admission to hospital.Conclusion: Our findings suggested that patients with severe illness might experience longer virus exposure times and have a stronger antibody response against viral infection. Thus, they have longer time immunity compared with other groups.

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Detailed Multiplex Analysis of SARS-CoV-2 Specific Antibodies in COVID-19 Disease

Frontiers in Immunology ◽

10.3389/fimmu.2021.695230 ◽

2021 ◽

Vol 12 ◽

Author(s):

Siggeir F. Brynjolfsson ◽

Hildur Sigurgrimsdottir ◽

Elin D. Einarsdottir ◽

Gudrun A. Bjornsdottir ◽

Brynja Armannsdottir ◽

...

Keyword(s):

Antibody Response ◽

Immunological Response ◽

Receptor Binding Domain ◽

Igg Antibody ◽

Nucleocapsid Proteins ◽

The Third ◽

Antibody Isotypes ◽

Iga Antibodies ◽

Set Up ◽

Antibody Levels

A detailed understanding of the antibody response against SARS-CoV-2 is of high importance, especially with the emergence of novel vaccines. A multiplex-based assay, analyzing IgG, IgM, and IgA antibodies against the receptor binding domain (RBD), spike 1 (S1), and nucleocapsid proteins of the SARS-CoV-2 virus was set up. The multiplex-based analysis was calibrated against the Elecsys® Anti-SARS-CoV-2 assay on a Roche Cobas® instrument, using positive and negative samples. The calibration of the multiplex based assay yielded a sensitivity of 100% and a specificity of 97.7%. SARS-CoV-2 specific antibody levels were analyzed by multiplex in 251 samples from 221 patients. A significant increase in all antibody types (IgM, IgG, and IgA) against RBD was observed between the first and the third weeks of disease. Additionally, the S1 IgG antibody response increased significantly between weeks 1, 2, and 3 of disease. Class switching appeared to occur earlier for IgA than for IgG. Patients requiring hospital admission and intensive care had higher levels of SARS-CoV-2 specific IgA levels than outpatients. These findings describe the initial antibody response during the first weeks of disease and demonstrate the importance of analyzing different antibody isotypes against multiple antigens and include IgA when examining the immunological response to COVID-19.

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A Cross-Sectional Study for Evaluation of KRAS and BRAF Mutations by Reverse Dot Blot, PCR-RFLP, and Allele-Specific PCR Methods Among Patients with Colorectal Cancer

Avicenna Journal of Medical Biotechnology ◽

10.18502/ajmb.v13i4.7203 ◽

2021 ◽

Author(s):

Fatemeh Sheikhsofla ◽

Behzad Poopak ◽

Sajjad Firuzyar ◽

Fatemeh Roudbari ◽

Mojtaba Ghadiany

Keyword(s):

Colorectal Cancer ◽

Gene Mutations ◽

Dot Blot ◽

Braf Mutations ◽

Kras Gene ◽

Specific Pcr ◽

Pcr Rflp ◽

Allele Specific ◽

Allele Specific Pcr ◽

Reverse Dot Blot

Background: KRAS and BRAF genes are the biomarkers in Colorectal Cancer (CRC) which play prognostic and predictive roles in CRC treatment. Nowadays, the selection of rapid and available methods for studying KRAS and BRAF mutations in anti-EGFR therapy of patients suffering from CRC plays a significant role. In this study, the mutations of these two oncogenes were evaluated by different methods. Methods: This study was performed on 50 Formalin-Fixed Paraffin-Embedded (FFPE) tissue blocks of patients diagnosed with colorectal cancer. After DNA extraction, KRAS and BRAF gene mutations were evaluated using reverse dot blot, and results were compared with PCR-RFLP and allele-specific PCR for KRAS and BRAF mutations, respectively. Results: KRAS gene mutations were detected in 42% of patients, of which 30% were in codon 12 region, and 12% in codon 13. The most frequent mutations of KRAS were related to G12D and 10% of patients had BRAF mutated genes. The type of KRAS gene mutations could be evaluated by reverse dot blot method. In general, the results of PCR-RFLP and allele-specific PCR were similar to the findings by reverse dot blot method. Conclusion: These findings suggest that PCR-RFLP and allele-specific PCR methods are suitable for screening the presence of the mutations in KRAS and BRAF oncogenes. In fact, another method with more sensitivity is needed for a more accurate assessment to determine the type of mutations. Due to higher speed of detection, reduced Turnaround Time (TAT), and possible role of some KRAS point mutations in overall survival, reverse dot blot analysis seems to be an optimal method.

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