scholarly journals Evaluation of Serum Antibody Responses against the Rotavirus Nonstructural Protein NSP4 in Children after Rhesus Rotavirus Tetravalent Vaccination or Natural Infection

2005 ◽  
Vol 12 (10) ◽  
pp. 1157-1163 ◽  
Author(s):  
Esmeralda Vizzi ◽  
Eva Calviño ◽  
Rosabel González ◽  
Irene Pérez-Schael ◽  
Max Ciarlet ◽  
...  
Keyword(s):  
Potential Role ◽  
Nonstructural Protein ◽  
Natural Infection ◽  
Seroconversion Rate ◽  
Serum Antibody ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Response ◽  
Rotavirus Diarrhea ◽  
Antibody Levels ◽  
Acute Phase Serum

ABSTRACT The immune response elicited by the rotavirus nonstructural protein NSP4 and its potential role in protection against rotavirus disease are not well understood. We investigated the serological response to NSP4 and its correlation with disease protection in sera from 110 children suffering acute diarrhea, associated or not with rotavirus, and from 26 children who were recipients of the rhesus rotavirus tetravalent (RRV-TV) vaccine. We used, as antigens in an enzyme-linked immunosorbent assay (ELISA), affinity-purified recombinant NSP4 (residues 85 to 175) from strains SA11, Wa, and RRV (genotypes A, B, and C, respectively) fused to glutathione S-transferase. Seroconversion to NSP4 was observed in 54% (42/78) of the children who suffered from natural rotavirus infection and in 8% (2/26) of the RRV-TV vaccine recipients. Our findings indicate that NSP4 evokes significantly (P < 0.05) higher seroconversion rates after natural infection than after RRV-TV vaccination. The serum antibody levels to NSP4 were modest (titers of ≤200) in most of the infected and vaccinated children. A heterotypic NSP4 response was detected in 48% of the naturally rotavirus-infected children with a detectable response to NSP4. Following natural infection or RRV-TV vaccination, NSP4 was significantly less immunogenic than the VP6 protein when these responses were independently measured by ELISA. A significant (P < 0.05) proportion of children who did not develop diarrhea associated with rotavirus had antibodies to NSP4 in acute-phase serum, suggesting that serum antibodies against NSP4 might correlate with protection from rotavirus diarrhea. In addition, previous exposures to rotavirus did not affect the NSP4 seroconversion rate.

Study of Antibody Levels in Children with Purulent Otitis Media

1980 ◽  
Vol 89 (3_suppl) ◽  
pp. 117-120 ◽  
Author(s):  
P. Branefors ◽  
T. Dahlberg ◽  
O. Nylén
Keyword(s):  
Otitis Media ◽  
Serum Antibody ◽  
Acute Otitis Media ◽  
High Serum ◽  
Haemophilus Influenzae Type ◽  
Enzyme Linked Immunosorbent Assay ◽  
Polysaccharide Antigens ◽  
Antibody Titers ◽  
Iga Antibody ◽  
Antibody Levels

A series of episodes of acute otitis media were studied with reference to the bacterial findings in the nasopharynx and the specific antibody response in a group of children nine months to ten years of age, with previous frequent episodes of acute otitis media, Serum IgG, IgM and IgA antibody levels against five polysaccharide antigens, namely Haemophilus influenzae type b and Streptococcus pneumoniae types 3, 6, 19 and 23, were studied by means of an enzyme-linked immunosorbent assay. The selection of polysaccharide antigens was based on isolation frequency. The sera to be tested were tenfold serially diluted. An extinction of 0.2 over the base was taken as the end-point titer and expressed as in-log10. The results showed that most children including those under three years of age showed increasing homologous antibody titers at an infection, or had already initially very high antibody titers, especially of the IgG class. The titers reached levels of 104 to 105. In some cases, however, it could be shown that high serum antibody titers did not give protection against a new infection with the same serological type of bacteria. It was also demonstrated that most children, regardless of age, had IgG and IgM titers against the heterologous antigens. In some cases the levels were quite high (103 to 104). However, the IgA antibody levels were lower and in a considerable number of samples antibodies were not even detectable.

scholarly journals Evaluation of Vaccination Strategy Against Rabies in Hong Kong Macaques

2021 ◽  
Author(s):  
Omid Nekouei ◽  
Paolo Martelli ◽  
Sophie St-Hilaire ◽  
Hui Suk Wai ◽  
Karthiyani Krishnasamy ◽  
...  
Keyword(s):  
Hong Kong ◽  
Vaccination Strategy ◽  
Elisa Test ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Response ◽  
Test Kit ◽  
In The Wild ◽  
The Government ◽  
Specific Association ◽  
Antibody Levels

Rabies is a fatal zoonotic disease that can affect all mammals. Following the directives of the rabies ordinance of the Government of Hong Kong, all wild macaques captured under an ongoing sterilization program (since 2000) were vaccinated against rabies. The main objective of this study was to assess the serological response to rabies vaccination in the population of Hong Kong macaques. An inactivated rabies vaccine was subcutaneously administered to captured macaques under anesthesia. In a 2015 field survey, blood samples from the animals were collected and stored in -80℃ freezer. In July 2021, all frozen sera from vaccinated animals were prepared and tested for antibodies against rabies virus using a commercial enzyme-linked immunosorbent assay (ELISA) test. The test results were dichotomized at the recommended cut-off point of the test kit. Sixty-five samples from the vaccinated macaques were available for this study. All of these animals had received at least one dose of vaccine (1 vaccination) between 2008 and 2015. The interval between the 1 vaccination and blood sampling dates ranged from 21 to 2,779 days. Only five of the 65 macaques had a second vaccination record at the time of sampling; all five had high antibody levels. Among the remaining macaques, 77% (46/60) were positive for rabies antibodies. No specific association was observed between the post-vaccination period and the antibody titer of these macaques and no adverse reactions to vaccination were reported. The current vaccination strategy in Hong Kong macaques appears to effectively elicit rabies antibodies in a high proportion of macaque populations in the wild (78-87%). However, reaching the precise level of protection against a potential challenge with the virus should further be investigated.

scholarly journals Immunoglobulin G Antibody against Helicobacter pylori: Clinical Implications of Levels Found in Serum

2002 ◽  
Vol 9 (5) ◽  
pp. 1044-1048 ◽  
Author(s):  
Tseng-Shing Chen ◽  
Fen-Yau Li ◽  
Full-Young Chang ◽  
Shou-Dong Lee
Keyword(s):  
Helicobacter Pylori ◽  
Chronic Gastritis ◽  
Predictive Value ◽  
Linear Regression Analysis ◽  
Serum Antibody ◽  
Quantitative Detection ◽  
Enzyme Linked Immunosorbent Assay ◽  
Multivariate Linear Regression Analysis ◽  
H Pylori ◽  
Antibody Levels

ABSTRACT The clinical significance of high levels of antibody against Helicobacter pylori is still unclear. We sought to evaluate whether the serum antibody levels could predict the presence of macroscopic gastroduodenal disease, to identify factors that correlate with antibody levels in a multivariate context, and to determine the predictive value of antibody levels for diagnosing H. pylori infection. The grades of gastritis and density of H. pylori colonization were scored separately using the updated Sydney system for antral and body mucosa. An enzyme-linked immunosorbent assay (ELISA) for the quantitative detection in serum of IgG antibodies to H. pylori was performed. Of the 170 dyspeptic patients, 105 (62%) had H. pylori infection. There was no difference in antibody levels among endoscopic findings of normal mucosa, chronic gastritis, and duodenal ulcer. On multivariate linear regression analysis, the status of H. pylori infection, mononuclear cell infiltration of body mucosa, and age correlated with antibody levels. The negative predictive value for antibody levels of <30 U/ml is 94%, and the positive predictive value of antibody levels of >70 U/ml is 98%. We conclude that serum antibody levels do not predict the severity of gastroduodenal diseases or the density of H. pylori colonization in H. pylori-infected dyspeptic patients. Higher levels are associated with the presence of H. pylori infection, the chronic gastritis score of the corpus, and older age. Setting a gray zone is necessary for ELISA, since the accuracy in this zone does not allow a precise determination of H. pylori status.

scholarly journals Development of a Nucleocapsid-Based Human Coronavirus Immunoassay and Estimates of Individuals Exposed to Coronavirus in a U.S. Metropolitan Population

2008 ◽  
Vol 15 (12) ◽  
pp. 1805-1810 ◽  
Author(s):  
Emily G. Severance ◽  
Ioannis Bossis ◽  
Faith B. Dickerson ◽  
Cassie R. Stallings ◽  
Andrea E. Origoni ◽  
...  
Keyword(s):  
Socioeconomic Status ◽  
Solid Phase ◽  
Smoking Status ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Response ◽  
Blood Draw ◽  
Increased Risk ◽  
Antibody Levels ◽  
Population Demographic ◽  
Feline Coronavirus

ABSTRACT Coronaviruses cause respiratory infections ranging from common colds to severe acute respiratory syndrome (SARS) in humans. Estimates for exposure to non-SARS coronaviruses are high, particularly for 229E and OC43; however, less information regarding seroprevalence is available for HKU1 and NL63. To measure exposure rates to these four coronavirus strains (229E, HKU1, NL63, and OC43), we devised an immunoassay based on amino- and carboxy-terminally tagged recombinant coronavirus nucleocapsid antigens. Four human and one feline coronavirus antigen were cloned into baculoviruses expressed in insect cells and recovered proteins bound in the solid phase of an enzyme-linked immunosorbent assay-based system. We screened sera from 10 children and 196 adults and established primary cutoff points based on immunoglobulin G (IgG) antibody levels of the predominantly seronegative children. The proportion of seropositive adults for each coronavirus was as follows: 229E, 91.3%; HKU1, 59.2%; NL63, 91.8%; and OC43, 90.8%. No evidence of a significant serological response to the feline coronavirus was observed. Significant associations of coronavirus seropositivity and antibody levels with age, gender, race, socioeconomic status, smoking status, and season of the blood draw were tested with chi-square and regression analyses. The group II coronaviruses (OC43 and HKU1) were significantly associated with race (P ≤ 0.009 and P ≤ 0.03, respectively). Elevated OC43 IgG levels were further significantly associated with smoking status (P ≤ 0.03), as were high NL63 titers with socioeconomic status (P ≤ 0.04). The high-level immunoreactivity of each coronavirus was significantly associated with the summer season (P ≤ 0.01 to 0.0001). In summary, high rates of exposure to 229E, NL63, and OC43 and a moderate rate of exposure to HKU1 characterized the seroprevalence among individuals in this population. Demographic factors, such as race, smoking status, and socioeconomic status, may confer an increased risk of susceptibility to these viruses.

Immunologic Response to Pneumococcal Polysaccharide Vaccine in Infants

1980 ◽  
Vol 89 (3_suppl) ◽  
pp. 351-356 ◽  
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.

scholarly journals Enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against foot-and-mouth disease virus: III. Evaluation of antibodies after infection and vaccination

1987 ◽  
Vol 99 (3) ◽  
pp. 733-744 ◽  
Author(s):  
C. Hamblin ◽  
R. P. Kitching ◽  
A. I. Donaldson ◽  
J. R. Crowther ◽  
I. T. R. Barnett
Keyword(s):  
Disease Virus ◽  
Immunosorbent Assay ◽  
Serum Antibody ◽  
Foot And Mouth Disease ◽  
Immunological Response ◽  
Mouth Disease ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Antibody Levels

SUMMARYInvestigations using a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (ELISA) for the measurement of antibodies against foot-and-mouth disease virus (FMDV) in sera from sheep and from cattle are reported, and results compared with those obtained by virus neutralization (VN) tests.Serum antibody titres in sheep after primary vaccination and in cattle challenged with a natural aerosol after vaccination were similar by ELISA and VN. However, the antibody levels detected in sera of cattle during early infection and of vaccinated cattle after intradermolingual challenge were clearly greater by ELISA than by VN.The ELISA titres in cattle sera following synthetic peptide vaccination indicated some relationship to protection and were clearly different from those recorded by VN. On the other hand, the antibody levels following conventional vaccination showed that ELISA and VN titres in cattle sera were related to protection. Although there was a good agreement between the ELISA antibody titre and protection for the four vaccines used, by VN the titre which afforded protection varied depending on the vaccine used.The ELISA was considered therefore to be more reliable than the VN and may prove useful for evaluating the immunological response of animals following infection and following vaccination.

scholarly journals Type-Specific Antibodies to Pneumococcal Capsular Polysaccharide Acquired either Naturally or after Vaccination with Prevenar in Children with Underlying Chronic or Recurrent Lung Diseases

2006 ◽  
Vol 13 (6) ◽  
pp. 665-670 ◽  
Author(s):  
David Navarro ◽  
Amparo Escribano ◽  
Laura Cebrián ◽  
Concepción Gimeno ◽  
Leonor García-Maset ◽  
...  
Keyword(s):  
Lung Diseases ◽  
Capsular Polysaccharide ◽  
Serum Antibody ◽  
Invasive Disease ◽  
Significant Rise ◽  
Enzyme Linked Immunosorbent Assay ◽  
Carrier Status ◽  
Specific Antibodies ◽  
Antibody Levels

ABSTRACT The antibody response to capsular polysaccharides of pneumococcal serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F elicited either naturally or after vaccination with Prevenar was investigated in a cohort of children (n = 163) with underlying chronic or recurrent lung diseases at risk of developing pneumococcal pneumonia and ultimately invasive disease. Serum concentrations of serotype-specific antibodies, as measured by enzyme-linked immunosorbent assay, in unvaccinated children (n = 88) were higher in nasopharyngeal carriers (n = 10) than in noncarriers (n = 78) both at baseline and during follow-up. However, the antibody levels depended on the serotype and age of the children. During the study period, 35% of unvaccinated noncarriers and 60% of unvaccinated carriers displayed serum antibodies to all serotypes above the reported WHO working group putative protective serum concentration against invasive disease (0.2 μg/ml). Overall, children vaccinated with Prevenar before enrollment (n = 61), irrespective of their carrier status, displayed significantly higher serum levels of antibodies to all serotypes than unvaccinated children. More than 85% of the vaccinated children had protective serum antibody concentrations at baseline; although antibody titers tended to decrease over time, the above-mentioned figure remained without change at the end of follow-up. The vaccine Prevenar elicited a significant rise in serum antibody concentrations against all serotypes in 14 children vaccinated at entry. All of these children acquired and maintained serum antibody levels of >0.2 μg/ml throughout the study (a mean of 13 months of follow-up). These data support the systematic use of the vaccine Prevenar in children with underlying chronic or recurrent lung diseases and stress the fact that a percentage of vaccinated children may need to be revaccinated in order to achieve protection against pneumococcal disease.

scholarly journals Infection with Plasmodium berghei Boosts Antibody Responses Primed by a DNA Vaccine Encoding Gametocyte Antigen Pbs48/45

2006 ◽  
Vol 74 (4) ◽  
pp. 2043-2051 ◽  
Author(s):  
Diana Haddad ◽  
Jorge Maciel ◽  
Nirbhay Kumar
Keyword(s):  
Immune Responses ◽  
Dna Vaccine ◽  
Plasmodium Berghei ◽  
Malaria Vaccine ◽  
Natural Infection ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Additional Control ◽  
Antibody Levels ◽  
Repeat Infection

ABSTRACT An important consideration in the development of a malaria vaccine for individuals living in areas of endemicity is whether vaccine-elicited immune responses can be boosted by natural infection. To investigate this question, we used Plasmodium berghei ANKA blood-stage parasites for the infection of mice that were previously immunized with a DNA vaccine encoding the P. berghei sexual-stage antigen Pbs48/45. Intramuscular immunization in mice with one or two doses of DNA-Pbs48/45 or of empty DNA vaccine as control did not elicit detectable anti-Pbs48/45 antibodies as determined by enzyme-linked immunosorbent assay. An infection with P. berghei ANKA 6 weeks after DNA vaccination elicited comparable anti-Pbs48/45 antibody levels in mice which had been primed with DNA-Pbs48/45 or with empty DNA vaccine. However, a repeat infection with P. berghei ANKA resulted in significantly higher anti-Pbs48/45 antibody levels in mice which had been primed with the DNA-Pbs48/45 vaccine than the levels in the mock DNA-vaccinated mice. In parallel and as an additional control to distinguish the boosting of Pbs48/45 antibodies exclusively by gametocytes during infection, a separate group of mice primed with DNA-Pbs48/45 received an infection with P. berghei ANKA clone 2.33, which was previously described as a “nongametocyte producer.” To our surprise, this parasite clone too elicited antibody levels comparable to those induced by the P. berghei gametocyte producer clone. We further demonstrate that the nongametocyte producer P. berghei clone is in fact a defective gametocyte producer that expresses Pbs48/45, much like the gametocyte producer clone, and is therefore capable of boosting antibody levels to Pbs48/45. Taken together, these results indicate that vaccine-primed antibodies can be boosted during repeat infections and warrant further investigation with additional malaria antigens.

Relationships between immune indicators of parasitic gastroenteritis, nematode burdens and faecal dry matter in sheep

2010 ◽  
Vol 50 (3) ◽  
pp. 219 ◽  
Author(s):  
A. R. Williams ◽  
D. G. Palmer ◽  
I. H. Williams ◽  
P. E. Vercoe ◽  
D. L. Emery ◽  
...  
Keyword(s):  
Light Chain ◽  
Dry Matter ◽  
Serum Antibody ◽  
Enzyme Linked Immunosorbent Assay ◽  
Interleukin 5 ◽  
Teladorsagia Circumcincta ◽  
Immune Mediated ◽  
Before And After ◽  
Parasitic Gastroenteritis ◽  
Antibody Levels

Immune-mediated scouring in sheep is a mucosal hypersensitivity response caused by ingesting infective parasite larvae. In this experiment we tested the hypothesis that levels of parasite-specific antibodies and also interleukin-5 (IL-5) would be negatively correlated with worm numbers, but also faecal dry matter (FDM), in parasite-resistant Merino sheep. Forty Merino rams were challenged with Trichostrongylus colubriformis and Teladorsagia circumcincta larvae every day for 6 weeks, after which they were euthanised and total worm burdens determined. Faecal samples were taken for measurement of worm egg counts and FDM. Serum was collected from the rams before and after the larval challenge commenced, and levels of ovine immunoglobulin light chain, IgG, IgM, IgA and IgE specific for T. colubriformis and T. circumcincta as well as IL-5 were determined by sandwich enzyme-linked immunosorbent assay. IL-5 and all serum antibodies apart from T. colubriformis-specific light chain were significantly increased by the larval challenge. However, none of the antibodies, or IL-5, was correlated with FDM. Negative correlations were observed between the number of adult T. circumcincta and antibody levels; however, there was little relationship between antibodies and numbers of T. colubriformis. It was concluded that serum antibody levels are a poor indicator of the susceptibility of sheep to immune-mediated scouring. Because of these results, sheep breeders should continue to select for low worm egg count and focus on phenotypic indicators of scouring, such as dags, as a means to reduce diarrhoea.

Sign in / Sign up

Export Citation Format

Share Document