scholarly journals SARS-CoV-2 Seroprevalence and Profiles Among Convalescents in Sichuan Province, China

2021 ◽  
Vol 9 ◽  
Author(s):  
Lijun Zhou ◽  
Cheng Li ◽  
Huiping Yang ◽  
Heng Yuan ◽  
Ming Pan ◽  
...  
Keyword(s):  
Associated Factors ◽  
Infection Type ◽  
Demographic Factors ◽  
Sichuan Province ◽  
Serum Samples ◽  
Travel History ◽  
Igm Antibodies ◽  
Igm Antibody ◽  
Antibody Levels

Objectives: To explore and understand the SARS-CoV-2 seroprevalence of convalescents, the association between antibody levels and demographic factors, and the seroepidemiology of convalescents of COVID-19 till March 2021.Methods: We recruited 517 voluntary COVID-19 convalescents in Sichuan Province and collected 1,707 serum samples till March 2021. Then we reported the seroprevalence and analyzed the associated factors.Results: Recent travel history was associated with IgM levels. Convalescents who had recent travel history were less likely to be IgM antibody negative [OR = 0.232, 95% CI: (0.128, 0.420)]. Asymptomatic cases had, approximately, twice the odds of being IgM antibody negative compared with symptomatic cases [OR = 2.583, 95% CI: (1.554, 4.293)]. Participants without symptoms were less likely to be IgG seronegative than those with symptoms [OR = 0.511, 95% CI: (0.293, 0.891)]. Convalescents aged 40–59 were less likely to be IgG seronegative than those aged below 20 [OR = 0.364, 95% CI: (0.138, 0.959)]. The duration of positive IgM antibodies persisted 365 days while the IgG persisted more than 399 days.Conclusions: Our findings suggested that recent travel history might be associated with the antibody levels of IgM, while age could be associated with the antibody levels of IgG. Infection type could be associated with both antibody levels of IgM and IgG that declined quicker in asymptomatic cases.

scholarly journals IgM and IgA Antibody Responses in 12 Cases of Human Acquired Toxoplasmosis

1997 ◽  
Vol 39 (6) ◽  
pp. 327-332 ◽  
Author(s):  
Emília E. H. TAKAHASHI ◽  
Cláudio L. ROSSI
Keyword(s):  
Serological Test ◽  
Clinical Manifestations ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Igm Antibodies ◽  
Iga Antibodies ◽  
Direct Elisa ◽  
Acute Toxoplasmosis ◽  
Antibody Levels ◽  
Acquired Toxoplasmosis

The persistence, in some subjects, of specific IgM antibodies to Toxoplasma gondii for several months after the acute phase of infection has complicated the interpretation of serological test results for toxoplasmosis. Several reports have emphasized the value of the detection of Toxoplasma-specific IgA antibodies for the diagnosis of acute toxoplasmosis. In this article, we report the follow-up profiles of Toxoplasma-specific IgM and IgA antibodies in serum samples obtained from 12 patients at various intervals after the onset of the clinical manifestations of infection. IgM antibodies were detected by the indirect immunofluorescence (IIF) test, antibody capture enzyme-linked immunosorbent assay (cELISA) and enzyme-mediated chemilluminescent technique (CmL). IgA antibodies were quantified by the direct ELISA (dELISA) and cELISA procedures. As defined by the manufacturer of the cELISA test for IgA used, most patients with acute toxoplasmosis have antibody levels > 40 arbritary units per ml (AU/ml). At values > 40 AU/ml, the cELISA for IgA detected significant antibody levels for a shorter time than the other techniques used for IgM and IgA detection. However, IgA levels <FONT FACE="Symbol">£</font> 40 AU/ml do not exclude the possibility of acute toxoplasmosis since such levels can be reached very soon after infection with T. gondii. The results obtained in the present study show that the serological diagnosis of acute toxoplasmosis may not be such an easy task. Our data suggest that use of the IgA-cELISA concomitantly with IgM antibody screening could permit, in some circumstances, a more efficient diagnosis of acute acquired toxoplasmosis

scholarly journals Serum antibodies to phosphatidylcholine in MS

2020 ◽  
Vol 7 (4) ◽  
pp. e765 ◽  
Author(s):  
Maria Cruz Sádaba ◽  
Veit Rothhammer ◽  
Úrsula Muñoz ◽  
Cristina Sebal ◽  
Esther Escudero ◽  
...  
Keyword(s):  
Serum Levels ◽  
Immunoglobulin M ◽  
Class Iii ◽  
Serum Antibodies ◽  
Serum Samples ◽  
Igm Antibodies ◽  
Elisa Technique ◽  
Antibody Levels ◽  
And Control ◽  
Control Samples

ObjectiveTo evaluate the value of serum immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies reactive with phosphatidylcholine (PC) and lactosylceramide (LC) as biomarkers in MS.MethodsWe developed an ultrasensitive ELISA technique to analyze serum IgG and IgM antibodies to LC and PC, which we used to analyze samples from 362 patients with MS, 10 patients with non-MS myelin diseases (Non-MSMYDs), 11 patients with nonmyelin neurologic diseases (Non-MYNDs), and 80 controls. MS serum samples included clinically isolated syndrome (CIS, n = 17), relapsing-remitting MS (RRMS, n = 62), secondary progressive MS (SPMS, n = 50), primary progressive MS (PPMS, n = 37), and benign MS (BENMS, n = 36).ResultsWe detected higher levels of serum IgM antibodies to PC (IgM-PC) in MS than control samples; patients with CIS and RRMS showed higher IgM-PC levels than patients with SPMS, PPMS, and BENMS and controls. MS and control samples did not differ in serum levels of IgM antibodies reactive with LC, nor in IgG antibodies reactive with LC or PC.ConclusionsSerum IgM-PC antibodies are elevated in patients with MS, particularly during the CIS and RRMS phases of the disease. Thus, serum IgM-PC is a candidate biomarker for early inflammatory stages of MS.Classification of evidenceThis study provides Class III evidence that serum antibodies to PC are elevated in patients with MS. The study is rated Class III because of the case control design and the risk of spectrum bias: antibody levels in patients with MS were compared with healthy controls.

Naturally occurring immunoglobulin Mantibodies toToxoplasma gondiiin Japanese populations

Parasitology ◽  
1991 ◽  
Vol 102 (2) ◽  
pp. 157-162 ◽  
Author(s):  
E. Konishi
Keyword(s):  
Gradient Centrifugation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Antibody Activity ◽  
Soluble Antigen ◽  
Sucrose Density Gradient Centrifugation ◽  
Igm Antibodies ◽  
Igm Antibody ◽  
Naturally Occurring ◽  
Antibody Levels ◽  
Natural Igm

SUMMARYVarying degrees of naturally occurring immunoglobulin (Ig) M antibodies toToxoplasma gondiiwere observed in almost all of adult Japanese populations negative for IgG antibodies as determined by an enzyme-linked immunosorbent assay (ELISA). The antibody activity was reduced by absorption of sera withToxoplasmasoluble antigen or by 2-mercapto-ethanol treatment of the IgM fraction after sucrose density gradient centrifugation. Umbilical cord sera had almost no detectable IgM antibodies, and the ELISA value in infants increased with age until 1 year. Most paired sera collected from adults at a 1-year interval showed constant IgM antibody levels, suggesting retention of natural IgM antibodies throughout their lives without changing ELISA values of ≥ 0·1/year. Polar staining was observed in immunofluorescent studies for 14 serum samples with natural IgM antibody levels of ≥ 0·5, while samples obtained from a pregnant woman with natural IgM antibody levels of ≥ 0·9 reacted to the whole organism as was observed in positive sera of acute patients. Western blotting analysis revealed that natural IgM antibodies were directed to multiple antigen molecules. The band pattern differed slightly from one serum to another, but almost consistent patterns were observed in sera sequentially obtained from an adult over 4 years.

Comparison of three anti-coccidioides antibody enzyme immunoassay kits for the diagnosis of coccidioidomycosis

2020 ◽  
Vol 58 (6) ◽  
pp. 774-778 ◽  
Author(s):  
Joshua Malo ◽  
Eric Holbrook ◽  
Tirdad Zangeneh ◽  
Chris Strawter ◽  
Eyal Oren ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Diagnostic Testing ◽  
High Risk Patient ◽  
Immunoglobulin M ◽  
Antibody Detection ◽  
Serum Samples ◽  
Igg Antibody ◽  
Igm Antibodies ◽  
Igm Antibody ◽  
Detection Specificity

Abstract Coccidioidomycosis is a common cause of community-acquired pneumonia in endemic areas of the southwestern United States. Clinical presentations range from self-limited disease to severe, disseminated disease. As such, early and accurate diagnosis is essential to ensure appropriate treatment and monitoring. Currently available diagnostic testing has variable accuracy, particularly in certain patient populations, and new tests may offer improved accuracy for the diagnosis of coccidioidomycosis. Serum samples from patients with coccidioidomycosis and controls were tested for immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies using the MVista Coccidioides antibody detection EIA and two commonly used commercial enzyme immunoassay (EIA) kits: the IMMY Omega EIA and the Meridian Premier EIA. The sensitivity of the IgG antibody detection was 87.4% using the MVista test compared to 46.6% for IMMY and 70.9% for Meridian. The sensitivity for IgM antibody detection was 61.2% for the MVista test, 22.3% for IMMY and 29.1% for Meridian. For IgG antibody detection, specificity was 90% for the MVista EIA, 94.6% for IMMY, 96.4% for Meridian. For IgM antibody detection, specificity was 95.3% for the MVista test 98.2% for IMMY and 99.1% for Meridian. The MVista Coccidioides antibody EIA offers improved sensitivity, including among high-risk patient populations, for the detection of IgG and IgM antibodies in comparison to other currently available EIAs.

scholarly journals Older Adults Have a Low Capacity To Opsonize Pneumococci Due to Low IgM Antibody Response to Pneumococcal Vaccinations

2010 ◽  
Vol 79 (1) ◽  
pp. 314-320 ◽  
Author(s):  
Saeyoung Park ◽  
Moon H. Nahm
Keyword(s):  
Older Adults ◽  
Young Adults ◽  
Age Groups ◽  
Functional Difference ◽  
Igg Antibody ◽  
Igm Antibodies ◽  
Igm Antibody ◽  
Significant Difference ◽  
The Difference ◽  
Antibody Levels

ABSTRACTSince the 23-valent pneumococcal polysaccharide vaccine (PPV23) is less effective for older adults than for young adults, it is important to investigate the immunologic basis for the reduced efficacy of PPV23 among older adults. We determined the effectiveness of PPV23 among young (n= 55) and older (n= 44) adults by measuring the serum IgG, IgM, and IgA concentrations and opsonic capacities against serotypes 14, 18C, and 23F. While young and older adults showed no difference in levels of IgG antibodies against pneumococcal polysaccharide (PPS), older adults had lower IgA and IgM antibody levels than young adults for all three serotypes. In both age groups, anti-PPS IgA or IgM antibody levels were much lower than anti-PPS IgG antibody levels. Young adults showed higher opsonic capacities than older adults for serotypes 14 and 23F. In order to determine the effects of anti-PPS IgA or IgM antibodies on the functional difference between young and older adults, anti-PPS IgA or IgM antibodies were removed from immune sera by affinity chromatography. The difference in opsonic capacity between young and older adults disappeared for serotypes 14 and 23F (but not for serotype 18C) when IgM antibody was removed. However, there was no significant difference between the two age groups when IgA antibody was removed. In conclusion, even though anti-PPS IgG antibody levels are high compared with anti-PPS IgM antibody levels, the low levels of anti-PPS IgM antibody alone can explain the functional difference observed between young and older adults immunized with PPV23 with regard to some pneumococcal serotypes.

scholarly journals Further evaluation of one-point microcapsule agglutination test for diagnosis of leptospirosis

1991 ◽  
Vol 106 (3) ◽  
pp. 561-565 ◽  
Author(s):  
J. J. Cui ◽  
G. X. Xiao ◽  
T. Z. Chen ◽  
G. F. Zhu ◽  
T. Sato ◽  
...  
Keyword(s):  
Acute Phase ◽  
Sichuan Province ◽  
Agglutination Test ◽  
Serum Samples ◽  
Early Stages ◽  
Igm Antibody ◽  
The One

SUMMARYA total of 100 serum samples including 22 acute phase sera and 39 paired sera collected from clinically diagnosed cases of leptospirosis in Ming-shan County, Sichuan Province, China were examined by the one-point microcapsule agglutination test (MCAT), which was developed in Japan, and by conventional microscopic agglutination tests (MAT). The one-point MCAT is more reactive to IgM antibody than MAT and is superior in detecting antibodies in the early stages of the disease.

scholarly journals Comparing Results of Five SARS-CoV-2 Antibody Assays Before and After the First Dose of ChAdOx1 nCoV-19 Vaccine among Health Care Workers

2021 ◽  
Author(s):  
Seri Jeong ◽  
Nuri Lee ◽  
Su Kyung Lee ◽  
Eun-Jung Cho ◽  
Jungwon Hyun ◽  
...  
Keyword(s):  
Health Care Workers ◽  
Symptom Severity ◽  
Associated Factors ◽  
Adverse Reactions ◽  
Serum Samples ◽  
Care Workers ◽  
Before And After ◽  
Antibody Assays ◽  
Paired Serum ◽  
Antibody Levels

Reliable results of serologic positivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody before and after AstraZeneca (AZ) vaccination are essential to estimate the efficacy of vaccination. We assessed the positivity rates and associated factors using five SARS-CoV-2 antibody assays. A total of 228 paired serum samples (456 samples) were obtained from 228 participants. After baseline sampling, the second sampling was conducted between 11-28 days after the first dose of AZ. Sera were tested using five SARS-CoV-2 antibody assays, including two surrogate virus neutralization tests. A questionnaire on symptom, severity, and duration of adverse reactions was completed by all participants. The overall positive rates for SARS-CoV-2 antibody were 84.6% for Roche, 92.5% for Abbott, 75.4% for Siemens, 90.7% for SD Biosensor, and 66.2% for GenScript assays after the first dose of AZ vaccination. The positive rates and antibody titer of sera obtained between 21-28 days were significantly higher than those obtained between 11-20 days in all five assays. More severe and longer duration of adverse reactions were related to higher SARS-CoV-2 antibody levels. The agreements and correlations among the applied assays were substantial (к=0.73-0.95) and strong (ρ=0.83-0.91). A single dose of AZ vaccination led to high positivity rates based on the five assays. Days after vaccination and adverse reactions could help estimate serologic conversions. The results should be interpreted cautiously considering the applied assays and cutoffs. Our findings could inform decisions regarding vaccination and laboratory settings and, thus, contribute to the control of the spread of SARS-CoV-2 infection.

scholarly journals In Schizophrenia, Low Natural IgM Antibody Titers to Oxidative Specific Epitopes and Higher IgM Responses to Nitrated and Nitrosylated Proteins Strongly Predict Negative Symptoms, Neurocognitive Impairments and the Deficit Syndrome

2018 ◽  
Author(s):  
Michael Maes ◽  
Buranee Kanchanatawan ◽  
Sunee Sirivichayakul ◽  
Andre F. Carvalho
Keyword(s):  
Episodic Memory ◽  
Azelaic Acid ◽  
Negative Symptoms ◽  
Primary Immune Response ◽  
Igm Antibodies ◽  
Deficit Schizophrenia ◽  
Igm Antibody ◽  
Antibody Titers ◽  
Antibody Levels ◽  
Natural Igm

Schizophrenia is characterized by an interrelated activation of the immune-inflammatory response system (IRS) and the compensatory immune-regulatory reflex system (CIRS), which downregulates the IRS. Deficit schizophrenia is characterized by a deficit in natural regulatory autoimmune responses to tryptophan catabolites. The presence and correlates of IgM isotype antibodies to oxidative specific epitopes (OSEs), nitroso (NO) and nitro (NO2) adducts in schizophrenia remain unknown.This study measured IgM antibodies to malondialdehyde (MDA), azelaic acid, phosphatidylinositol, oleic acid, NO-tryptophan, NO-albumin, NO-cysteinyl and NO2-tyrosine in a sample of 80 schizophrenia patients, divided into those with and those without deficit schizophrenia, and 38 healthy controls.Deficit schizophrenia was characterized by significantly lower IgM antibody levels to all OSEs as compared with non-deficit schizophrenia and controls. Lowered IgM antibodies to MDA coupled with increased IgM levels to NO-cysteinyl and NO2-tyrosine strongly predict deficit schizophrenia versus non-deficit schizophrenia with an area under the ROC curve of 0.913. A large part of the variance (21.2 &ndash; 42.2 %) in the negative symptoms of schizophrenia and excitation is explained by IgM antibody titers to MDA (inversely) and NO-cysteinyl and/or NO2-tyrosine (both positively). Lower IgM antibodies to MDA are significantly associated with impairments in episodic memory including direct and delayed recall.These findings further indicate that deficit schizophrenia is a distinct phenotype of schizophrenia, which is characterized by lower natural IgM antibody levels to OSEs and relative increments in nitrosylation and nitration of proteins. It is concluded that deficits in lowered IgM responses to MDA and azelaic acid (part of the CIRS) attenuate the negative immune-regulatory feedback on the primary immune response and that this process may drive negative symptoms and impairments in episodic memory and thus deficit schizophrenia.

scholarly journals In Schizophrenia, Low Natural IgM Antibody Titers to Oxidative Specific Epitopes and Higher IgM Responses to Nitrated and Nitrosylated Proteins Strongly Predict Negative Symptoms, Neurocognitive Impairments and the Deficit Syndrome

2018 ◽  
Author(s):  
Michael Maes ◽  
Buranee Kanchanatawan ◽  
Sunee Sirivichayakul ◽  
Andre F. Carvalho
Keyword(s):  
Episodic Memory ◽  
Azelaic Acid ◽  
Negative Symptoms ◽  
Primary Immune Response ◽  
Igm Antibodies ◽  
Deficit Schizophrenia ◽  
Igm Antibody ◽  
Antibody Titers ◽  
Antibody Levels ◽  
Natural Igm

Schizophrenia is characterized by an interrelated activation of the immune-inflammatory response system (IRS) and the compensatory immune-regulatory reflex system (CIRS), which downregulates the IRS. Deficit schizophrenia is characterized by a deficit in natural regulatory autoimmune responses to tryptophan catabolites. The presence and correlates of IgM isotype antibodies to oxidative specific epitopes (OSEs), nitroso (NO) and nitro (NO2) adducts in schizophrenia remain unknown.This study measured IgM antibodies to malondialdehyde (MDA), azelaic acid, phosphatidylinositol, oleic acid, NO-tryptophan, NO-albumin, NO-cysteinyl and NO2-tyrosine in a sample of 80 schizophrenia patients, divided into those with and those without deficit schizophrenia, and 38 healthy controls.Deficit schizophrenia was characterized by significantly lower IgM antibody levels to all OSEs as compared with non-deficit schizophrenia and controls. Lowered IgM antibodies to MDA coupled with increased IgM levels to NO-cysteinyl and NO2-tyrosine strongly predict deficit schizophrenia versus non-deficit schizophrenia with an area under the ROC curve of 0.913. A large part of the variance (21.2 &ndash; 42.2 %) in the negative symptoms of schizophrenia and excitation is explained by IgM antibody titers to MDA (inversely) and NO-cysteinyl and/or NO2-tyrosine (both positively). Lower IgM antibodies to MDA are significantly associated with impairments in episodic memory including direct and delayed recall.These findings further indicate that deficit schizophrenia is a distinct phenotype of schizophrenia, which is characterized by lower natural IgM antibody levels to OSEs and relative increments in nitrosylation and nitration of proteins. It is concluded that deficits in lowered IgM responses to MDA and azelaic acid (part of the CIRS) attenuate the negative immune-regulatory feedback on the primary immune response and that this process may drive negative symptoms and impairments in episodic memory and thus deficit schizophrenia.

Naturally occurring immunoglobulin M antibodies: enhancement of phagocytic and microbicidal activities of human neutrophils againstToxoplasma gondii

Parasitology ◽  
1992 ◽  
Vol 104 (3) ◽  
pp. 427-432 ◽  
Author(s):  
E. Konishi ◽  
M. Nakao
Keyword(s):  
Early Stage ◽  
Immunoglobulin M ◽  
Human Neutrophils ◽  
Microscopical Examination ◽  
Igm Antibodies ◽  
Igm Antibody ◽  
Naturally Occurring ◽  
Human Sera ◽  
Antibody Levels ◽  
Natural Igm

Naturally occurring immunoglobulin M antibodies toToxoplasma gondiiin human sera were examined for their ability to enhance toxoplasmacidal activities of human neutrophils to show a role of natural antibodies in immunity to the early stage ofToxoplasmainfection in humans. Neutrophils were mixed with tachyzoites at a ratio of 1:5 in the presence or absence of antibodies and were cultured for 1–18 h for microscopical examination. The count of tachyzoites phagocytosed in 200 neutrophils within 1 h was significantly higher in the presence of sera with natural IgM antibody levels of > 0.8 than those of < 0.1, with 2.4- to 2.9-fold differences (P< 0.02). The total tachyzoite counts at 18 h decreased to 26–39% of those at 1 h in the presence of natural IgM antibody levels of > 0.8 (P< 0.01), while the counts at 1 h consistently increased by 18 h in the absence of natural IgM antibodies. These results indicate that relatively high levels of natural IgM antibodies enhanced phagocytic and microbicidal activities of neutrophils againstToxoplasma. The enhancement was dose dependent, and was also weaker than that obtained with the same dilution of sera from individuals with chronic or acute infections. Live and dead tachyzoite counts in infected neutrophils suggested a quicker effect of natural IgM antibodies than IgG antibodies elicited by infection.

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