scholarly journals 405. Serum Antibody Responses Against Carbapenem-Resistant Klebsiella pneumoniae in Infected Patients

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S206-S206
Author(s):  
Kasturi Banerjee ◽  
Michael Motley ◽  
Elizabeth Diago-Navarro ◽  
Bettina C Fries
Keyword(s):  
Therapeutic Potential ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Size Exclusion ◽  
Enzyme Linked Immunosorbent Assay ◽  
Affinity Column ◽  
Carbapenem Resistant ◽  
Potential Vaccine ◽  
Clade 1 ◽  
Humoral Responses

Abstract Background Capsular polysaccharide (CPS) of Carbapenem-resistant K. pneumoniae ST258 (CR-Kp) is a potential vaccine target. CPS of these isolates generally falls within 2 homology groups named clade 1 and clade 2. We and others have made antibodies (Abs) that act against clade2 CR-Kp but failed to make therapeutic Abs against clade1 CR-Kp. Previous studies had shown that studying patient’s antibody responses could help in identifying suitable candidates for developing immunotherapies. Thus, we sought to identify potential vaccine candidates by investigating the humoral response CPS in CR-Kp-infected patients. Methods 24 CR-Kp isolates and corresponding serums were collected from inpatients at Stony Brook Hospital. CPS was isolated and purified by size-exclusion column chromatography from CR-Kp strains 34 (clade 2), 36 (clade 1), and 38 (clade-Other). Anti-CPS Abs in patient’s serum were detected by enzyme-linked immunosorbent assay (ELISA) and bulk Abs from positive serum were purified using an affinity column. These Abs were tested for activity against CR-Kp by serum bactericidal and agglutination assays. Results 50% of clade2 CR-Kp-infected patients had humoral responses against CPS34. 77% of clade 1-infected patients sera cross-reacted wtih CPS34, but none of them developed Abs against CPS36. Interestingly, 90% of clade1 and 60% of clade 2-infected patients, respectively, showed Abs binding to CPS38. Thus, we selectively purified Anti-CPS Abs from two clade-Other-infected patients and observed that they were cross-reactive with all three CPS. Further, these Anti-CPS Abs agglutinated all tested CR-Kp isolates (34, 36, and 38) when compared with control human IgG (P < 0.005). Additionally, these Anti-CPS Abs promoted killing of clade2 bacteria and inhibited the growth of clade1 bacteria in Ab-mediated serum bactericidal assay. These data elucidate that humoral responses developed in clade-Other CR-Kp-infected patients have therapeutic potential. Conclusion With the unavailability of effective antimicrobials for CR-Kp, approaches like developing novel anti-CPS vaccine could serve as an alternate therapy. Our data suggest that developing immunotherapies targeting CPS38 could potentially provide protection across both clade1 and clade2 bacteria in clinical settings. Disclosures All authors: No reported disclosures.

scholarly journals Purified Hexameric Epstein-Barr Virus-Encoded BARF1 Protein for Measuring Anti-BARF1 Antibody Responses in Nasopharyngeal Carcinoma Patients

2010 ◽  
Vol 18 (2) ◽  
pp. 298-304 ◽  
Author(s):  
E. K. Hoebe ◽  
S. H. Hutajulu ◽  
J. van Beek ◽  
S. J. Stevens ◽  
D. K. Paramita ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Epstein Barr Virus ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Humoral Immune ◽  
Barr Virus ◽  
Humoral Immune Responses ◽  
Human Sera ◽  
Epstein Barr ◽  
Humoral Responses

ABSTRACTWHO type III nasopharyngeal carcinoma (NPC) is highly prevalent in Indonesia and 100% associated with Epstein-Barr virus (EBV). NPC tumor cells express viral proteins, including BARF1, which is secreted and is considered to have oncogenic and immune-modulating properties. Recently, we found conserved mutations in the BARF1 gene in NPC isolates. This study describes the expression and purification of NPC-derived BARF1 and analyzes humoral immune responses against prototype BARF1 (B95-8) and purified native hexameric BARF1 in sera of Indonesian NPC patients (n= 155) compared to healthy EBV-positive (n= 56) and EBV-negative (n= 16) individuals. BARF1 (B95-8) expressed inEscherichia coliand baculovirus, as well as BARF1-derived peptides, did not react with IgG or IgA antibodies in NPC. Purified native hexameric BARF1 protein isolated from culture medium was used in enzyme-linked immunosorbent assay (ELISA) and revealed relatively weak IgG and IgA responses in human sera, although it had strong antibody responses to other EBV proteins. Higher IgG reactivity was found in NPC patients (P= 0.015) than in regional Indonesian controls or EBV-negative individuals (P< 0.001). IgA responses to native BARF1 were marginal. NPC sera with the highest IgG responses to hexameric BARF1 in ELISA showed detectable reactivity with denatured BARF1 by immunoblotting. In conclusion, BARF1 has low immunogenicity for humoral responses and requires native conformation for antibody binding. The presence of antibodies against native BARF1 in the blood of NPC patients provides evidence that the protein is expressed and secreted as a hexameric protein in NPC patients.

scholarly journals Serum Antibody Responses against Carbapenem-Resistant Klebsiella pneumoniae in Infected Patients

mSphere ◽  
2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Kasturi Banerjee ◽  
Michael P. Motley ◽  
Elizabeth Diago-Navarro ◽  
Bettina C. Fries
Keyword(s):  
Klebsiella Pneumoniae ◽  
Capsular Polysaccharide ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Capsular Polysaccharides ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Reactive Properties

ABSTRACT Capsular polysaccharide (CPS) heterogeneity within carbapenem-resistant Klebsiella pneumoniae (CR-Kp) strain sequence type 258 (ST258) must be considered when developing CPS-based vaccines. Here, we sought to characterize CPS-specific antibody responses elicited by CR-Kp-infected patients. Plasma and bacterial isolates were collected from 33 hospital patients with positive CR-Kp cultures. Isolate capsules were typed by wzi sequencing. Reactivity and measures of efficacy of patient antibodies were studied against 3 prevalent CR-Kp CPS types (wzi29, wzi154, and wzi50). High IgG titers against wzi154 and wzi50 CPS were documented in 79% of infected patients. Patient-derived (PD) IgGs agglutinated CR-Kp and limited growth better than naive IgG and promoted phagocytosis of strains across the serotype isolated from their donors. Additionally, poly-IgG from wzi50 and wzi154 patients promoted phagocytosis of nonconcordant CR-Kp serotypes. Such effects were lost when poly-IgG was depleted of CPS-specific IgG. Additionally, mice infected with wzi50, wzi154, and wzi29 CR-Kp strains preopsonized with wzi50 patient-derived IgG exhibited lower lung CFU than controls. Depletion of wzi50 antibodies (Abs) reversed this effect in wzi50 and wzi154 infections, whereas wzi154 Ab depletion reduced poly-IgG efficacy against wzi29 CR-Kp. We are the first to report cross-reactive properties of CPS-specific Abs from CR-Kp patients through both in vitro and in vivo models. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae is a rapidly emerging public health threat that can cause fatal infections in up to 50% of affected patients. Due to its resistance to nearly all antimicrobials, development of alternate therapies like antibodies and vaccines is urgently needed. Capsular polysaccharides constitute important targets, as they are crucial for Klebsiella pneumoniae pathogenesis. Capsular polysaccharides are very diverse and, therefore, studying the host’s capsule-type specific antibodies is crucial to develop effective anti-CPS immunotherapies. In this study, we are the first to characterize humoral responses in infected patients against carbapenem-resistant Klebsiella pneumoniae expressing different wzi capsule types. This study is the first to report the efficacy of cross-reactive properties of CPS-specific Abs in both in vitro and in vivo models.

scholarly journals Serum Antibody Responses to 10 Mycobacterium tuberculosis Proteins, Purified Protein Derivative, and Old Tuberculin in Natural and Experimental Tuberculosis in Rhesus Monkeys

2011 ◽  
Vol 18 (12) ◽  
pp. 2154-2160 ◽  
Author(s):  
Fangui Min ◽  
Yu Zhang ◽  
Ren Huang ◽  
Wende Li ◽  
Yu'e Wu ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Rhesus Monkeys ◽  
Skin Testing ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Antibody Detection ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tuberculin Skin Testing ◽  
Purified Protein Derivative ◽  
Diagnostic Potential

ABSTRACTOld tuberculin (OT) and purified protein derivative (PPD) are widely used for tuberculin skin testing (TST) in diagnosis of tuberculosis (TB) but often yield poor specificity and anergy in reaction. Therefore, it is necessary to develop new serological methods as a possible auxiliary diagnostic method for TB. In this study, we characterized the dynamic antibody responses of 10 purified recombinant antigens, PPD, and OT in rhesus monkeys experimentally infected withMycobacterium tuberculosisand analyzed the time to antibody detection, antibody levels, and their association with the infectious doses. The antibodies were detected as early as 4 weeks after infection in response to 5 antigens (CFP10, CFP10-ESAT-6, U1, MPT64, and Ag85b). Antibodies against most of the other antigens were detected between 4 and 12 weeks after infection. The levels of antibodies were dose dependant. We further evaluated the serodiagnostic potential of these antigens by using indirect enzyme-linked immunosorbent assay in 71 TST-positive and 90 TST-negative serum samples from monkeys. For all 12 antigens, the median optical density values of TST-positive monkeys were statistically significantly higher than those of TST-negative monkeys (P< 0.001). Among those antigens, Ag85b and CFP10 showed higher diagnostic potential than others. A combination of results from Ag85b, the 38-kDa antigen (Ag38kDa), and Ag14kDa reaches a sensitivity of 95.77%, indicating that these antigens may be ideal cocktails in TB diagnosis.

scholarly journals Decreased Serum Antibody Responses to RecombinantPneumocystisAntigens in HIV-Infected and Uninfected Current Smokers

2010 ◽  
Vol 18 (3) ◽  
pp. 380-386 ◽  
Author(s):  
Kristina Crothers ◽  
Kieran R. Daly ◽  
David Rimland ◽  
Matthew Bidwell Goetz ◽  
Cynthia L. Gibert ◽  
...  
Keyword(s):  
Antibody Response ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Surface Glycoprotein ◽  
Enzyme Linked Immunosorbent Assay ◽  
Chronic Obstructive ◽  
Tobit Regression ◽  
Serum Samples ◽  
Cross Sectional ◽  
Prospective Longitudinal

ABSTRACTSerologic studies can provide important insights into the epidemiology and transmission ofPneumocystis jirovecii. Exposure toP. jiroveciican be assessed by serum antibody responses to recombinant antigens from the major surface glycoprotein (MsgC), although factors that influence the magnitude of the antibody response are incompletely understood. We determined the magnitudes of antibody responses toP. jiroveciiin comparison to adenovirus and respiratory syncytial virus (RSV) in HIV-infected and uninfected patients and identified predictors associated with the magnitude of the response. We performed a cross-sectional analysis using serum samples and data from 153 HIV-positive and 92 HIV-negative subjects enrolled in a feasibility study of the Veterans Aging Cohort 5 Site Study (VACS 5). Antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). Independent predictors of antibody responses were determined using multivariate Tobit regression models. The results showed that serum antibody responses toP. jiroveciiMsgC fragments were significantly and independently decreased in current smokers. Antibodies toP. jiroveciialso tended to be lower with chronic obstructive pulmonary disease (COPD), hazardous alcohol use, injection drug use, and HIV infection, although these results were not statistically significant. These results were specific toP. jiroveciiand did not correlate with adenovirus. Antibody responses to RSV were in the inverse direction. Thus, current smoking was independently associated with decreasedP. jiroveciiantibody responses. Whether smoking exerts an immunosuppressive effect that affects theP. jiroveciiantibody response, colonization, or subsequent risk for disease is unclear; prospective, longitudinal studies are needed to evaluate these findings further.

scholarly journals Orally Administered Giardia duodenalis Extracts Enhance an Antigen-Specific Antibody Response

2001 ◽  
Vol 69 (10) ◽  
pp. 6503-6510 ◽  
Author(s):  
Linda A. Dunn ◽  
Jacqueline A. Upcroft ◽  
Elizabeth V. Fowler ◽  
Ben S. Matthews ◽  
Peter Upcroft
Keyword(s):  
Serum Antibody ◽  
Giardia Duodenalis ◽  
Complete Characterization ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Adjuvant Activity ◽  
Specific Antibody Response ◽  
Specific Serum ◽  
Serum Response

ABSTRACT We have identified novel adjuvant activity in specific cytosol fractions from trophozoites of Giardia isolate BRIS/95/HEPU/2041 (J. A. Upcroft, P. A. McDonnell, and P. Upcroft, Parasitol. Today, 14:281–284, 1998). Adjuvant activity was demonstrated in the systemic and mucosal compartments when Giardia extract was coadministered orally with antigen to mice. Enhanced antigen-specific serum antibody responses were demonstrated by enzyme-linked immunosorbent assay to be comparable to those generated by the “gold standard,” mucosal adjuvant cholera toxin. A source of adjuvant activity was localized to the cytosolic component of the parasite. Fractionation of the cytosol produced fraction pools, some of which, when coadministered with antigen, stimulated an enhanced antigen-specific serum response. The toxic component of conventional mucosal adjuvants is associated with adjuvant activity; therefore, in a similar way, the toxin-like attributes of BRIS/95/HEPU/2041 may be responsible for its adjuvanticity. Complete characterization of the adjuvant is under way.

scholarly journals Antibody Responses in Reindeer (Rangifer tarandus) Infected with Mycobacterium bovis

2005 ◽  
Vol 12 (6) ◽  
pp. 727-735 ◽  
Author(s):  
W. R. Waters ◽  
M. V. Palmer ◽  
J. P. Bannantine ◽  
R. Greenwald ◽  
J. Esfandiari ◽  
...  
Keyword(s):  
Mycobacterium Bovis ◽  
Specific Antibody ◽  
Rangifer Tarandus ◽  
Skin Testing ◽  
Serum Antibody ◽  
The United States ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cell Mediated Immunity ◽  
Testing Procedures

ABSTRACT Despite having a very low incidence of disease, reindeer (Rangifer tarandus) are subject to tuberculosis (TB) testing requirements for interstate shipment and herd accreditation in the United States. Improved TB tests are desperately needed, as many reindeer are falsely classified as reactors by current testing procedures. Sera collected sequentially from 11 (experimentally) Mycobacterium bovis-infected reindeer and 4 noninfected reindeer were evaluated by enzyme-linked immunosorbent assay (ELISA), immunoblotting, and multiantigen print immunoassay (MAPIA) for antibody specific to M. bovis antigens. Specific antibody was detected as early as 4 weeks after challenge with M. bovis. By MAPIA, sera were tested with 12 native and recombinant antigens, which were used to coat nitrocellulose. All M. bovis-infected reindeer developed responses to MPB83 and a fusion protein, Acr1/MPB83, and 9/11 had responses to MPB70. Other antigens less commonly recognized included MPB59, ESAT-6, and CFP10. Administration of purified protein derivatives for skin testing boosted serum antibody responses, as detected by each of the assays. Of the noninfected reindeer, 2/4 had responses that were detectable immediately following skin testing, which correlated with pathological findings (i.e., presence of granulomatous lesions yet the absence of acid-fast bacteria). The levels of specific antibody produced by infected reindeer appeared to be associated with disease progression but not with cell-mediated immunity. These findings indicate that M. bovis infection of reindeer elicits an antibody response to multiple antigens that can be boosted by skin testing. Serological tests using carefully selected specific antigens have potential for early detection of infections in reindeer.

scholarly journals Antibody Responses of Cattle Immunized with the Tf190 Adhesin of Tritrichomonas foetus

2001 ◽  
Vol 8 (6) ◽  
pp. 1120-1125 ◽  
Author(s):  
Jovanka M. Voyich ◽  
Raymond Ansotegui ◽  
Connie Swenson ◽  
John Bailey ◽  
Donald E. Burgess
Keyword(s):  
Immune Responses ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Response Patterns ◽  
Tritrichomonas Foetus ◽  
Antigen Specificity ◽  
Specific Enzyme ◽  
Subcutaneous Injections ◽  
Mammalian Cell Lines

ABSTRACT The antibody response patterns of cattle after subcutaneous and intranasal immunizations with adhesin Tf190 of Tritrichomonas foetus were investigated. Reactions of antibody from cattle parenterally immunized with Tf190 revealed antigen specificity and Tf190 sensitization in the majority of the animals, as determined by Western blotting. The results also demonstrated strong preimmune immunoglobulin G2 (IgG2) binding to T. foetus antigens not seen in IgG1 profiles. Subcutaneous injections of Tf190 resulted in significant (P < 0.05) increases in serum IgG1 and IgG2 titers over time, as determined by parasite specific enzyme-linked immunosorbent assay. Immune sera also significantly inhibited parasite adhesion to mammalian cell lines compared to the level of inhibition obtained with preimmune sera (P < 0.05). Intranasal immunization with Tf190 failed to produce measurable parasite-specific antibody in serum; however, this immunization route did result in significant (P < 0.05) increases in parasite-specific IgA titers in cervical mucus secretions from immunized animals that were more resistant to intravaginal challenge with T. foetus than controls. These results suggest that systemic immunization with Tf190 results in serum antibody production and antiparasitic adhesin antibodies. Additionally, the results of challenge experiments with intranasally immunized animals suggests that Tf190 primes protective immune responses that lead to lower rates of infection among these animals.

scholarly journals Carbohydrate Biopolymers Enhance Antibody Responses to Mucosally Delivered Vaccine Antigens

2000 ◽  
Vol 68 (10) ◽  
pp. 5764-5770 ◽  
Author(s):  
A. Bacon ◽  
J. Makin ◽  
P. J. Sizer ◽  
I. Jabbal-Gill ◽  
M. Hinchcliffe ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Influenza B ◽  
Virus Surface ◽  
Parenteral Immunization ◽  
Iga Response ◽  
Nasal Secretions

ABSTRACT We have evaluated the ability of two carbohydrate biopolymers, chitosan and gellan, to enhance antibody responses to subunit influenza virus vaccines delivered to the respiratory tracts of mice. Groups of mice were vaccinated three times intranasally (i.n.) with 10 μg of purified influenza B/Panama virus surface antigens (PSAs), which consist of hemagglutinin (HA) and neuraminidase (NA), either alone or admixed with chitosan or gellan solutions. Separate groups were vaccinated subcutaneously (s.c.) with PSAs adsorbed to Alhydrogel or chitosan or gellan alone i.n. Serum antibody responses were determined by enzyme-linked immunosorbent assay (ELISA) for influenza virus-specific immunoglobulin G (IgG) and by HA inhibition (HAI) and NA inhibition (NAI) assays. The local respiratory immune response was measured by assaying for influenza virus-specific IgA antibody in nasal secretions and by enumerating nasal and pulmonary lymphocytes secreting IgA, IgG, and IgM anti-influenza virus-specific antibodies by enzyme-linked immunospotting (ELISPOT). When administered alone i.n., B/Panama PSA was poorly immunogenic. Parenteral immunization with B/Panama PSA with Alhydrogel elicited high titers of anti-B/Panama antibodies in serum but a very poor respiratory anti-B/Panama IgA response. In contrast, i.n. immunization with PSA plus chitosan stimulated very strong local and systemic anti-B/Panama responses. Gellan also enhanced the local and serum antibody responses to i.n. PSA but not to the same extent as chitosan. The ability of chitosan to augment the immunogenicity of influenza vaccines given i.n. was confirmed using PSA prepared from an influenza A virus (A/Texas H1N1).

scholarly journals Systemic and Cutaneous Mucus Antibody Responses of Channel Catfish Immunized against the Protozoan Parasite Ichthyophthirius multifiliis

2003 ◽  
Vol 10 (5) ◽  
pp. 876-881 ◽  
Author(s):  
Joanne L. Maki ◽  
Harry W. Dickerson
Keyword(s):  
Ictalurus Punctatus ◽  
Channel Catfish ◽  
Serum Antibody ◽  
Protozoan Parasite ◽  
Mean Value ◽  
Infected Fish ◽  
Antibody Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Ichthyophthirius Multifiliis ◽  
Antibody Levels

ABSTRACT Fish acquire protective immunity against the ciliated protozoan parasite Ichthyophthirius multifiliis following sublethal infection or inoculation with I. multifiliis immobilization antigens (i-antigens). In both cases, parasite-immobilizing antibodies have been identified in sera and mucosal secretions. To investigate the kinetics of this immune response, antibody levels were determined by enzyme-linked immunosorbent assay (ELISA) in the sera and cutaneous mucus of channel catfish (Ictalurus punctatus) that were either infected with parasites or given a single injection of purified i-antigen (5.0 μg/fish) in Freund's incomplete adjuvant. At 5 weeks, infected and inoculated fish had a mean serum (1:80 dilution) antibody absorbance (A 405) value of 0.54 ± 0.17 and 0.35 ± 0.03, respectively, which were significantly higher (α = 0.05) than the pretreatment serum (1:80 dilution) antibody absorbance value of 0.24 ± 0.05. At 14 weeks, mean serum (1:80 dilution) ELISA absorbance values in the teo groups of fish increased to 0.79 ± 0.30 and 0.71 ± 0.24, respectively. In both groups of fish, antibody levels in cutaneous mucus (undiluted) were much lower than those in sera. Infected fish had detectable mucus (undiluted) antibody levels from 3 to 9 weeks, with the highest mean value (0.30 ± 0.07) occurring at 7 weeks. Although individual inoculated fish produced serum antibody absorbance values comparable to those seen in infected fish, the mean mucus antibody values in this group did not rise above pretreatment levels. I. multifiliis infection induced a transient mucosal antibody response that coincided with the resolution of infection. Whether elicited by infection or intraperitoneal injection of i-antigen, the serum and mucus antibody responses of channel catfish immunized against I. multifiliis did not occur synchronously.

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