Influence of Exogenous Reproductive Hormones on Specific Antibody Production in Genital Secretions after Vaginal Vaccination with Recombinant Cholera Toxin B Subunit in Humans

ABSTRACT The objective of this study was to investigate the influence of exogenous reproductive hormones on the local and systemic production of specific immunoglobulin A (IgA) and IgG antibodies after vaginal vaccination with recombinant cholera toxin subunit B (CTB). Three groups of women using either progesterone-containing intrauterine devices (n = 9), oral contraceptives (n = 8), or no hormonal contraceptive methods (n = 9) were vaginally immunized twice, 2 weeks apart. Cervical secretions, vaginal fluids, and serum were collected before and after vaccination. Total and CTB-specific IgA and IgG antibodies in genital secretions and serum were analyzed by enzyme-linked immunosorbent assay. A majority of the women presented strong CTB-specific IgA and IgG antibody responses in cervicovaginal secretions after vaccination, whereas the antitoxin responses in serum were weaker. Exogenously administered steroid hormones did not seem to have any impact on the production of specific antibodies. Both the frequencies and the magnitudes of IgA and IgG antitoxin responses in genital secretions were comparable among the three immunization groups. An association, in particular for IgA, was found between the magnitudes of the CTB-specific antibody responses in cervical secretions and vaginal fluids after vaccination. The sensitivities and positive predictive values of vaginal antibody analyses to reflect responses in cervical secretions were also high, suggesting that vaginal fluids alone might be used for evaluation of genital immune responses in large-scale vaccination studies in the future.

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Antibody Responses to MAP 1B and Other Cowdria ruminantium Antigens Are Down Regulated in Cattle Challenged with Tick-Transmitted Heartwater

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.8.2.388-396.2001 ◽

2001 ◽

Vol 8 (2) ◽

pp. 388-396 ◽

Cited By ~ 17

Author(s):

S. M. Semu ◽

T. F. Peter ◽

D. Mukwedeya ◽

A. F. Barbet ◽

F. Jongejan ◽

...

Keyword(s):

Tick Infestation ◽

Repeated Exposure ◽

Antibody Responses ◽

Enzyme Linked Immunosorbent Assay ◽

Infected Cattle ◽

Igg Antibodies ◽

Igg Antibody ◽

Cowdria Ruminantium ◽

Infection Pressure ◽

Specific Igg

ABSTRACT Serological diagnosis of heartwater or Cowdria ruminantium infection has been hampered by severe cross-reactions with antibody responses to related ehrlichial agents. A MAP 1B indirect enzyme-linked immunosorbent assay that has an improved specificity and sensitivity for detection of immunoglobulin G (IgG) antibodies has been developed to overcome this constraint (A. H. M. van Vliet, B. A. M. Van der Zeijst, E. Camus, S. M. Mahan, D. Martinez, and F. Jongejan, J. Clin. Microbiol. 33:2405–2410, 1995). When sera were tested from cattle in areas of endemic heartwater infection in Zimbabwe, only 33% of the samples tested positive in this assay despite a high infection pressure (S. M. Mahan, S. M. Samu, T. F. Peter, and F. Jongejan, Ann. N.Y. Acad. Sci 849:85–87, 1998). To determine underlying causes for this observation, the kinetics of MAP 1B-specific IgG antibodies in cattle after tick-transmitted C. ruminantium infection and following recovery were investigated. Sera collected weekly over a period of 52 weeks from 37 cattle, which were naturally or experimentally infected with C. ruminantium via Amblyomma hebraeum ticks, were analyzed. MAP 1B-specific IgG antibody responses developed with similar kinetics in both field- and laboratory-infected cattle. IgG levels peaked at 4 to 9 weeks after tick infestation and declined to baseline levels between 14 and 33 weeks, despite repeated exposure to infected ticks and the establishment of a carrier state as demonstrated by PCR and xenodiagnosis. Some of the serum samples from laboratory, and field-infected cattle were also analyzed by immunoblotting and an indirect fluorescent-antibody test (IFAT) to determine whether this observed seroreversion was specific to the MAP 1B antigen. Reciprocal IFAT and immunoblot MAP 1-specific antibody titres peaked at 5 to 9 weeks after tick infestation but also declined between 30 and 45 weeks. This suggests that MAP 1B-specific IgG antibody responses and antibody responses to other C. ruminantium antigens are down regulated in cattle despite repeated exposure to C. ruminantium via ticks. Significantly, serological responses to the MAP 1B antigen may not be a reliable indicator of C. ruminantium exposure in cattle in areas of endemic heartwater infection.

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Detection of Genotype-Specific Antibody Responses to Glycoproteins B and H in Primary and Non-Primary Human Cytomegalovirus Infections by Peptide-Based ELISA

Viruses ◽

10.3390/v13030399 ◽

2021 ◽

Vol 13 (3) ◽

pp. 399

Author(s):

Federica Zavaglio ◽

Loretta Fiorina ◽

Nicolás M. Suárez ◽

Chiara Fornara ◽

Marica De Cicco ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Primary Infection ◽

Antibody Responses ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Igg Antibody ◽

Background Strain ◽

Specific Igg ◽

Cytomegalovirus Infections ◽

Specific Igg Antibodies

Background: Strain-specific antibodies to human cytomegalovirus (HCMV) glycoproteins B and H (gB and gH) have been proposed as a potential diagnostic tool for identifying reinfection. We investigated genotype-specific IgG antibody responses in parallel with defining the gB and gH genotypes of the infecting viral strains. Methods: Subjects with primary (n = 20) or non-primary (n = 25) HCMV infection were studied. The seven gB (gB1-7) and two gH (gH1-2) genotypes were determined by real-time PCR and whole viral genome sequencing, and genotype-specific IgG antibodies were measured by a peptide-based enzyme-linked immunosorbent assay (ELISA). Results: Among subjects with primary infection, 73% (n = 8) infected by gB1-HCMV and 63% (n = 5) infected by gB2/3-HCMV had genotype-specific IgG antibodies to gB (gB2 and gB3 are similar in the region tested). Peptides from the rarer gB4-gB7 genotypes had nonspecific antibody responses. All subjects infected by gH1-HCMV and 86% (n = 6) infected by gH2-HCMV developed genotype-specific responses. Among women with non-primary infection, gB and gH genotype-specific IgG antibodies were detected in 40% (n = 10) and 80% (n = 20) of subjects, respectively. Conclusions: Peptide-based ELISA is capable of detecting primary genotype-specific IgG responses to HCMV gB and gH, and could be adopted for identifying reinfections. However, about half of the subjects did not have genotype-specific IgG antibodies to gB.

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Kinetics of Local and Systemic Immune Responses after Vaginal Immunization with Recombinant Cholera Toxin B Subunit in Humans

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.12.3.447-452.2005 ◽

2005 ◽

Vol 12 (3) ◽

pp. 447-452 ◽

Cited By ~ 8

Author(s):

Lotta Wassen ◽

Marianne Jertborn

Keyword(s):

Immune Responses ◽

Cholera Toxin ◽

Female Genital Tract ◽

Antibody Responses ◽

Cholera Toxin B Subunit ◽

Igg Antibody ◽

Toxin B ◽

Cholera Toxin B ◽

B Subunit ◽

Kinetics Of

ABSTRACT Vaginal vaccination seems to be the best strategy for inducing specific immunoglobulin A (IgA) and IgG antibody responses in the female genital tract. The relative efficiencies of one, two, and three vaginal doses of recombinant cholera toxin B subunit (CTB) in generating mucosal and systemic immune responses in healthy women were evaluated, and the kinetics of the immune responses were monitored for responding volunteers for up to 12 months after the last vaccination. A single dose of CTB failed to generate CTB-specific IgA antibody responses in cervical secretions. Two vaccinations induced significant increases in IgA antitoxin titers in seven of nine volunteers, and four volunteers also developed IgG antitoxin responses. The magnitudes of the responses were 20-fold for IgA antitoxin and 7.1-fold for IgG antitoxin. A third vaccination did not significantly increase the antitoxin responses, although the frequency of IgG responses was slightly higher than that after the second vaccination. In serum, CTB-specific antibodies were observed already after a single vaccination. However, two vaccinations were required to induce marked IgA as well as IgG antitoxin titer increases in the majority of volunteers. The postvaccination levels of antitoxin antibodies in serum were comparable after two and three vaccinations. At 12 months after vaccination, significantly elevated IgA and IgG antitoxin levels in cervical secretions could still be detected in approximately half of the volunteers who had initially responded to the vaccine. Antitoxin titer increases in serum were found in most of the vaccinees at follow-up.

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Induction of Systemic Antifimbria and Antitoxin Antibody Responses in Egyptian Children and Adults by an Oral, Killed Enterotoxigenic Escherichia coli plus Cholera Toxin B Subunit Vaccine

Infection and Immunity ◽

10.1128/iai.69.5.2853-2857.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 2853-2857 ◽

Cited By ~ 38

Author(s):

Eric R. Hall ◽

Thomas F. Wierzba ◽

Christina Åhrén ◽

Malla R. Rao ◽

Samir Bassily ◽

...

Keyword(s):

Escherichia Coli ◽

Cholera Toxin ◽

Enterotoxigenic Escherichia Coli ◽

Enzyme Linked Immunosorbent Assay ◽

Cholera Toxin B Subunit ◽

Igg Antibodies ◽

Toxin B ◽

Cholera Toxin B ◽

B Subunit ◽

Egyptian Children

ABSTRACT We assessed serologic responses to an oral, killed whole-cell enterotoxigenic Escherichia coli plus cholera toxin B-subunit (ETEC-rCTB) vaccine in 73 Egyptian adults, 105 schoolchildren, and 93 preschool children. Each subject received two doses of vaccine or placebo 2 weeks apart, giving blood before immunization and 7 days after each dose. Plasma antibodies to rCTB and four vaccine-shared colonization factors (CFs) were measured by enzyme-linked immunosorbent assay. Immunoglobulin A (IgA) antibodies to rCTB and CFA/I were measured in all subjects, and those against CS1, CS2, and CS4 were measured in all children plus a subset of 33 adults. IgG antibodies to these five antigens were measured in a subset of 30 to 33 subjects in each cohort. Seroconversion was defined as a >2-fold increase in titer after vaccination. IgA and IgG seroconversion to rCTB was observed in 94 to 95% of adult vaccinees, with titer increases as robust as those previously reported for these two pediatric cohorts. The proportion showing IgA seroconversion to each CF antigen among vaccinated children (range, 70 to 96%) and adults (31 to 69%), as well as IgG seroconversion in children (44 to 75%) and adults (25 to 81%), was significantly higher than the corresponding proportion in placebo recipients, except for IgA responses to CS2 in adults. IgA anti-CF titers peaked after one dose in children, whereas in all age groups IgG antibodies rose incrementally after each dose. Independently, both preimmunization IgA titer and age were inversely related to the magnitude of IgA responses. In conclusion, serologic responses to the ETEC-rCTB vaccine may serve as practical immune outcome measures in future pediatric trials in areas where ETEC is endemic.

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Development and Validation of 13-plex Luminex-Based Assay for Measuring Human Serum Antibodies to Streptococcus pneumoniae Capsular Polysaccharides

mSphere ◽

10.1128/msphere.00128-18 ◽

2018 ◽

Vol 3 (4) ◽

pp. e00128-18 ◽

Cited By ~ 9

Author(s):

Danka Pavliakova ◽

Peter C. Giardina ◽

Soraya Moghazeh ◽

Shite Sebastian ◽

Maya Koster ◽

...

Keyword(s):

Human Serum ◽

Lower Limit ◽

Immunosorbent Assay ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Igg Antibody ◽

Correlate Of Protection ◽

Immune Correlate ◽

Relative Standard ◽

Limit Of Quantitation

ABSTRACT A Luminex-based direct immunoassay (dLIA) platform has been developed to replace the standardized pneumococcal enzyme-linked immunosorbent assay platform. The multiplex dLIA simultaneously measures the concentration of serum immunoglobulin G (IgG) antibodies specific for pneumococcal capsular polysaccharide (PnPS) serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F. The assay uses poly-l-lysine (PLL)-conjugated PnPS, chemically coupled to spectrally distinct Luminex microspheres. Assay validation experiments were performed using residual human serum samples obtained from 13-valent pneumococcal conjugate vaccine (13vPnC) clinical studies. Assay results are expressed as IgG antibody concentrations in micrograms per milliliter using the international reference serum, 007sp. The lower limit of quantitation (LLOQ) for all serotypes covered in the 13-plex dLIA fell within the range of 0.002 to 0.038 µg/ml serum IgG. The difference between the lower limit and upper limit of the assay range was >500-fold for all serotypes, and assay variability was <20% relative standard deviation (RSD) for all serotypes. IgG antibody measurements were shown to be serotype-specific (some cross-reactivity was observed only between the structurally related serotypes 6A and 6B as well as 19A and 19F), and no interference was observed between the serotypes when the assay was performed in the 13-plex format compared to the singleplex assays. The 13-plex dLIA platform developed by Pfizer Inc. generates up to 143 test results in a single 96-well plate and is a suitable replacement of the enzyme-linked immunosorbent assay (ELISA) platform for evaluating vaccine clinical trials. IMPORTANCE The pneumococcal enzyme-linked immunosorbent assay (ELISA) measures IgG antibodies in human serum, and it is an important assay that supports licensure of pneumococcal vaccines. The immune correlate of protection, 0.35 µg/ml of IgG antibodies, was determined by the ELISA method. Pfizer has developed a new Luminex-based assay platform to replace the ELISA. These papers describe the important work of (i) validating the Luminex-based assay and (ii) bridging the immune correlate of protection (0.35 µg/ml IgG) to equivalent values reported by the Luminex platform.

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Simultaneous Immunization with Multiple Diverse Immunogens Alters Development of Antigen-Specific Antibody-Mediated Immunity

Vaccines ◽

10.3390/vaccines9090964 ◽

2021 ◽

Vol 9 (9) ◽

pp. 964

Author(s):

Kelsey A. Pilewski ◽

Kevin J. Kramer ◽

Ivelin S. Georgiev

Keyword(s):

Specific Antibody ◽

Antibody Responses ◽

Surface Proteins ◽

Emerging Pathogens ◽

Igg Antibody ◽

Neisseria Meningitides ◽

Immunization Strategies ◽

Single Antigen ◽

The Face ◽

Antibody Titers

Vaccination remains one of the most successful medical interventions in history, significantly decreasing morbidity and mortality associated with, or even eradicating, numerous infectious diseases. Although traditional immunization strategies have recently proven insufficient in the face of many highly mutable and emerging pathogens, modern strategies aim to rationally engineer a single antigen or cocktail of antigens to generate a focused, protective immune response. However, the effect of cocktail vaccination (simultaneous immunization with multiple immunogens) on the antibody response to each individual antigen within the combination, remains largely unstudied. To investigate whether immunization with a cocktail of diverse antigens would result in decreased antibody titer against each unique antigen in the cocktail compared to immunization with each antigen alone, we immunized mice with surface proteins from uropathogenic Escherichia coli, Mycobacterium tuberculosis, and Neisseria meningitides, and monitored the development of antigen-specific IgG antibody responses. We found that antigen-specific endpoint antibody titers were comparable across immunization groups by study conclusion (day 70). Further, we discovered that although cocktail-immunized mice initially elicited more robust antibody responses, the rate of titer development decreases significantly over time compared to single antigen-immunized mice. Investigating the basic properties that govern the development of antigen-specific antibody responses will help inform the design of future combination immunization regimens.

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Preliminary Serological Study of Helicobacter pylori Infection in Some University Students

Recent Advances in Biology and Medicine ◽

10.18639/rabm.2020.958557 ◽

2020 ◽

Vol 6 ◽

pp. 1

Author(s):

Abdullah A Mahrazi ◽

Mohammad A Khibrani ◽

Khatib S Ismail ◽

Emad Abada ◽

◽

...

Keyword(s):

Helicobacter Pylori ◽

University Students ◽

Large Scale ◽

Confirmatory Test ◽

Enzyme Linked Immunosorbent Assay ◽

Blood Collection ◽

Igg Antibodies ◽

Igm Antibodies ◽

H Pylori

Helicobacter pylori has been associated with peptic ulcer and gastric carcinoma. This study aimed to find the seroprevalence of H. pylori infection in some male students of Jazan University, Saudi Arabia. Twenty students were enrolled in the study (n = 20). Informed consent was obtained from the students. About 2 ml blood was collected intravenously in Improvacuter® evacuated blood collection tubes. The blood was allowed to clot at room temperature. The serum was collected and stored at –20°C for further use. The separated serum was used to detect IgG and IgM antibodies by Enzyme Linked Immunosorbent Assay (ELISA) against H. pylori for the in vitro diagnosis. A total of 11 (55.00%) students tested positive for IgG antibodies against H. pylori indicating previous infection. All the samples tested negative for IgM antibodies against H. pylori indicating no active infection. The seroprevalance of IgG antibodies against H. pylori was found to be very high in some male university students and is a cause of concern regarding their health. Obesity (p < 0.05; Value statistically significant), stress and bad eating habits, eating out, drinking carbonated beverages, and eating spicy food were some of the factors found to be associated with IgG seropositive students. The students were counseled and were instructed to undergo a confirmatory test and get medical intervention. Further large-scale studies need to be performed to plan action against this disease causing organism and to improve the health of students.

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Detection of antibodies to recombinant truncated flagellin and sonicated whole cell antigen of Burkholderia pseudomallei in acute melioidosis and in healthy Bangladeshi individuals

IMC Journal of Medical Science ◽

10.3329/imcjms.v14i1.47455 ◽

2020 ◽

Vol 14 (1) ◽

pp. 47-52

Author(s):

Md Shariful Alam Jilani ◽

Tang Thean Hock ◽

Sraboni Mazumder ◽

Fahmida Rahman ◽

Md Mohiuddin ◽

...

Keyword(s):

Rural Areas ◽

Burkholderia Pseudomallei ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Healthy Individuals ◽

Serum Samples ◽

Igg Antibody ◽

Whole Cell ◽

Cell Antigen ◽

The Mean

Background and objectives: Several types of Burkholderia pseudomallei antigens have been used to determine the antibody response in acute and asymptomatic cases. In the present study, we have detected immunoglobulin G (IgG) antibody to recombinant truncated flagellin antigen (RTFA) of B. pseudomallei in the sera of acute melioidosis cases and healthy individuals from melioidosis endemic areas of Bangladesh by indirect enzyme-linked immunosorbent assay (ELISA). In parallel, IgG antibody to sonicated whole cell antigen (SWCA) of B. pseudomallei was determined to compare with anti-RTFA antibody. Methodology: Serum samples from culture confirmed melioidosis cases and from healthy individuals aged 21 years and above residing in melioidosis endemic rural areas were included in the study. Serum IgG antibody to RTFA and SWCA of B. pseudomallei was determined by indirect ELISA. Results: Out of 8 culture confirmed acute melioidosis cases, 7 (87.5%) and 8 (100%) were positive for anti-B. pseudomallei IgG antibodies by RTFA and SWCA methods respectively. Among 361 healthy individuals, the rate of seropositivity by RTFA-ELISA was significantly less than that of SWCA-ELISA (16.1% versus 26.8%; p = 0.001). The mean optical density (OD) of RTFA-ELISA of positive cases was significantly less than that of SWCA-ELISA in both melioidosis and healthy individuals (0.79±0.11 versus 2.4±0.08, p = 0.0001; 0.67±0.01 versus 1.27±0.02, p = 0.0001). The sensitivity and specificity of RTFA-ELISA were 88.9% and 100% respectively. Conclusion: Findings of the study suggest that multiple or combination of antigens should be used to study the seroprevalence of B. pseudomallei infection in a community. Also, prospective study is necessary to find out the duration of persistence of antibodies to different antigenic components of B. pseudomallei after exposure. Ibrahim Med. Coll. J. 2020; 14(1): 47-52

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