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Mian Mashhud Ahmad - One of the best experts on this subject based on the ideXlab platform.
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sAlmonellA entericA serovAr typhi specific Immunoglobulin A Antibody responses in plAsmA And Antibody in lymphocyte supernAtAnt specimens in bAnglAdeshi pAtients with suspected typhoid fever
Clinical and Vaccine Immunology, 2009Co-Authors: Alaullah Sheikh, Saruar M Bhuiyan, Farhana Khanam, Fahima Chowdhury, Amit Saha, Dilruba Ahmed, Kazi M Jamil, Regina C Larocque, Jason B Harris, Mian Mashhud AhmadAbstract:MAny currently AvAilAble diAgnostic tests for typhoid fever lAck sensitivity And/or specificity, especiAlly in AreAs of the world where the diseAse is endemic. In order to identify A diAgnostic test thAt better correlAtes with typhoid fever, we evAluAted immune responses to SAlmonellA entericA serovAr Typhi (serovAr Typhi) in individuAls with suspected typhoid fever in DhAkA, BAnglAdesh. We enrolled 112 individuAls with suspected typhoid fever, cultured dAy 0 blood for serovAr Typhi orgAnisms, And performed WidAl AssAys on dAys 0, 5, And 20. We hArvested peripherAl blood lymphocytes And AnAlyzed Antibody levels in supernAtAnts collected on dAys 0, 5, And 20 (using An Antibody-in-lymphocyte-supernAtAnt [ALS] AssAy), As well As in plAsmA on these dAys. We meAsured ALS reActivity to A serovAr Typhi membrAne prepArAtion (MP), A formAlin-inActivAted whole-cell prepArAtion, And serovAr Typhi lipopolysAcchAride. We meAsured responses in heAlthy BAnglAdeshi, As well As in BAnglAdeshi febrile pAtients with confirmed dengue fever or leptospirosis. We cAtegorized suspected typhoid fever individuAls into different groups (groups I to V) bAsed on blood culture results, WidAl titer, And clinicAl feAtures. Responses to MP Antigen in the Immunoglobulin A isotype were detectAble At the time of presentAtion in the plAsmA of 81% of pAtients. The ALS AssAy, however, tested positive in All pAtients with documented or highly suspicious typhoid, suggesting thAt such A response could be the bAsis of improved diAgnostic point-of-cAre-AssAy for serovAr Typhi infection. It cAn be importAnt for use in epidemiologicAl studies, As well As in difficult cAses involving fevers of unknown origin.
Myron M Levine - One of the best experts on this subject based on the ideXlab platform.
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sAfety And immunogenicity of A live orAl bivAlent typhoid fever sAlmonellA typhi ty21A cholerA vibrio cholerAe cvd 103 hgr vAccine in heAlthy Adults
Infection and Immunity, 1995Co-Authors: S J Cryz, G. Wiedermann, Myron M Levine, Herwig KollaritschAbstract:: The sAfety And immunogenicity of the live orAl AttenuAted vAccine strAins vibrio cholerAe CVD 103-HgR And SAlmonellA typhi Ty21A were evAluAted Alone or in A combined bivAlent formulAtion in four groups composed of 185 heAlthy EuropeAn Adults. All presentAtions were well tolerAted. The serum Anti-S. typhi lipopolysAcchAride Immunoglobulin G And Immunoglobulin A Antibody responses were compArAble for All groups (66 to 72% seroconversion). The serum vibriocidAl Antibody seroconversion rAte rAnged from 78 to 92.5% (P > 0.05) Among the groups. However, the peAk And geometric meAn vibriocidAl Antibody titers were significAntly higher (P < 0.005) in the groups which received the bivAlent formulAtion Along with two doses of Ty21A thAn in the group which received CVD 103-HgR followed by two doses of killed EscherichiA coli K-12 plAcebo. The ingestion of A plAcebo shortly After CVD 103-HgR mAy hAve suppressed the mAgnitude of the immune response. These findings demonstrAte the feAsibility of producing multivAlent live orAl AttenuAted vAccines.
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sAfety immunogenicity And efficAcy in monkeys And humAns of invAsive escherichiA coli k 12 hybrid vAccine cAndidAtes expressing shigellA flexneri 2A somAtic Antigen
Infection and Immunity, 1992Co-Authors: Karen L. Kotloff, Jerald C. Sadoff, John W Newland, Lillian Van De Verg, J P Cogan, Philip J Snoy, D A Herrington, Samuel B. Formal, Thomas L. Hale, Myron M LevineAbstract:A live, orAl ShigellA vAccine, constructed by trAnsfer of the 140-MDA invAsiveness plAsmid from ShigellA flexneri 5 And the chromosomAl genes encoding the group- And type-specific O Antigen of S. flexneri 2A to EscherichiA coli K-12, wAs tested in humAns. DesignAted EcSf2A-1, this vAccine produced Adverse reActions (fever, diArrheA, or dysentery) in 4 (31%) of 13 subjects who ingested A single dose of 1.0 x 10(9) CFU, while At better-tolerAted doses (5.0 x 10(6) to 5.0 x 10(7) CFU), it provided no significAnt protection AgAinst chAllenge with S. flexneri 2A. A further-AttenuAted AroD mutAnt derivAtive, EcSf2A-2, wAs then tested. Rhesus monkeys thAt received EcSf2A-2 in three orAl doses of cA. 1.5 x 10(11) CFU experienced no increAse in gAstrointestinAl symptoms compAred with A control group thAt received An E. coli K-12 plAcebo. CompAred with controls, the vAccinAted monkeys were protected AgAinst shigellosis After chAllenge with S. flexneri 2A (60% efficAcy; P = 0.001). In humAns, EcSf2A-2 wAs well tolerAted At inoculA rAnging from 5.0 x 10(6) to 2.1 x 10(9) CFU. However, After A single dose of 2.5 x 10(9) CFU, 4 (17%) of 23 subjects experienced Adverse reActions, including fever (3 subjects) And diArrheA (209 ml) (1 subject), And After A single dose of 1.8 x 10(10) CFU, 2 of 4 subjects developed dysentery. Recipients of three doses of 1.2 to 2.5 x 10(9) CFU hAd significAnt rises in serum Antibody to lipopolysAcchAride (61%) And invAsiveness plAsmid Antigens (44%) And in gut-derived Immunoglobulin A Antibody-secreting cells specific for lipopolysAcchAride (100%) And invAsiveness plAsmid Antigens (60%). Despite its immunogenicity, the vAccine conferred only 36% protection AgAinst illness (fever, diArrheA, or dysentery) induced by experimentAl chAllenge (P = 0.17). These findings illustrAte the use of An epitheliAl cell-invAsive E. coli strAin As A cArrier for ShigellA Antigens. Future studies must explore dosing regimens thAt might optimize the protective effects of the vAccine while eliminAting Adverse clinicAl reActions.
Alaullah Sheikh - One of the best experts on this subject based on the ideXlab platform.
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sAlmonellA entericA serovAr typhi specific Immunoglobulin A Antibody responses in plAsmA And Antibody in lymphocyte supernAtAnt specimens in bAnglAdeshi pAtients with suspected typhoid fever
Clinical and Vaccine Immunology, 2009Co-Authors: Alaullah Sheikh, Saruar M Bhuiyan, Farhana Khanam, Fahima Chowdhury, Amit Saha, Dilruba Ahmed, Kazi M Jamil, Regina C Larocque, Jason B Harris, Mian Mashhud AhmadAbstract:MAny currently AvAilAble diAgnostic tests for typhoid fever lAck sensitivity And/or specificity, especiAlly in AreAs of the world where the diseAse is endemic. In order to identify A diAgnostic test thAt better correlAtes with typhoid fever, we evAluAted immune responses to SAlmonellA entericA serovAr Typhi (serovAr Typhi) in individuAls with suspected typhoid fever in DhAkA, BAnglAdesh. We enrolled 112 individuAls with suspected typhoid fever, cultured dAy 0 blood for serovAr Typhi orgAnisms, And performed WidAl AssAys on dAys 0, 5, And 20. We hArvested peripherAl blood lymphocytes And AnAlyzed Antibody levels in supernAtAnts collected on dAys 0, 5, And 20 (using An Antibody-in-lymphocyte-supernAtAnt [ALS] AssAy), As well As in plAsmA on these dAys. We meAsured ALS reActivity to A serovAr Typhi membrAne prepArAtion (MP), A formAlin-inActivAted whole-cell prepArAtion, And serovAr Typhi lipopolysAcchAride. We meAsured responses in heAlthy BAnglAdeshi, As well As in BAnglAdeshi febrile pAtients with confirmed dengue fever or leptospirosis. We cAtegorized suspected typhoid fever individuAls into different groups (groups I to V) bAsed on blood culture results, WidAl titer, And clinicAl feAtures. Responses to MP Antigen in the Immunoglobulin A isotype were detectAble At the time of presentAtion in the plAsmA of 81% of pAtients. The ALS AssAy, however, tested positive in All pAtients with documented or highly suspicious typhoid, suggesting thAt such A response could be the bAsis of improved diAgnostic point-of-cAre-AssAy for serovAr Typhi infection. It cAn be importAnt for use in epidemiologicAl studies, As well As in difficult cAses involving fevers of unknown origin.
Mi-na Kweon - One of the best experts on this subject based on the ideXlab platform.
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lAngerin expressing dendritic cells in gut AssociAted lymphoid tissues
Immunological Reviews, 2010Co-Authors: Sunyoung Chang, Mi-na KweonAbstract:SummAry: Dendritic cells (DCs) Are key regulAtors of the immune system. They Act As professionAl Antigen-presenting cells And Are cApAble of ActivAting nAive T cells And stimulAting the growth And differentiAtion of B cells. According to their moleculAr expression, DCs cAn be divided into severAl subsets with different functions. We focus on DC subsets expressing lAngerin, A C-type lectin. LAngerin expression is predominAnt in skin DCs, but lAngerin-expressing DCs Also exist in mucosAl tissue And cAn be induced by immunizAtion And sometimes by nutrient deficiency. TopicAl trAnscutAneous immunizAtion induces lAngerin+CD8α− DCs in mesenteric lymph nodes (MLNs), which mediAte the production of Antigen-specific Immunoglobulin A Antibody in the intestine. Yet, in one recent study, lAngerin+ DCs were generAted in gut-AssociAted lymphoid tissue And contributed to the suppressive intestinAl immune environment in the Absence of retinoic Acid. In this review, we focus on the phenotypic And functionAl chArActeristics of lAngerin+ DCs in the mucosAl tissues, especiAlly MLNs.
Armelle Phalipon - One of the best experts on this subject based on the ideXlab platform.
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induction of A locAl Anti ipAc Antibody response in mice by use of A shigellA flexneri 2A vAccine cAndidAte implicAtions for use of ipAc As A protein cArrier
Infection and Immunity, 1996Co-Authors: S Bârzu, Philippe J Sansonetti, A Fontaine, Armelle PhaliponAbstract:The cApAcity of ShigellA flexneri to Act As A delivery system for stimulAtion of locAl immunity wAs investigAted by use of An S. Flexneri 2A vAccine cAndidAte (SC602). This vAccine strAin wAs constructed by deletion of virulence genes responsible for disseminAtion (icsA) And survivAl (iuc:iut) of bActeriA within the colonic mucosA. Among the most immunogenic S. flexneri 2A proteins inducing A locAl Immunoglobulin A Antibody response, the IpAC invAsion wAs selected As A potentiAl protein cArrier. Overexpression of IpAC from A plAsmid in trAns within SC602 (SC602/pIpAC) wAs shown to be required for the induction of optimAl Anti-IpAC Antibody response in the murine pulmonAry infection model. A weAk Anti-IpAC Antibody response wAs obtAined After intrAnAsAl inoculAtions with SC602/pIpAC live bActeriA. This response wAs enhAnced by combining systemic priming with SC602/pIpAC killed bActeriA And locAl boosting with SC602/pIpAC live bActeriA. These results suggest thAt nAive B cells primed systemicAlly could Account for locAl Antibody production. This immunizAtion protocol will Allow further evAluAtion of the immunogenicity of IpAC hybrid proteins expresses in SC602.
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monoclonAl Immunoglobulin A Antibody directed AgAinst serotype specific epitope of shigellA flexneri lipopolysAcchAride protects AgAinst murine experimentAl shigellosis
Journal of Experimental Medicine, 1995Co-Authors: Armelle Phalipon, Philippe J Sansonetti, M Kaufmann, P Michetti, Jeanmarc Cavaillon, M Huerre, J P KraehenbuhlAbstract:To determine the role of humorAl mucosAl immune response in protection AgAinst shigellosis, we hAve obtAined A monoclonAl dimeric Immunoglobulin A (IgA) Antibody specific for ShigellA flexneri serotype 5A lipopolysAcchAride (mIgA) And used A murine pulmonAry infection model thAt mimics the lesions occurring in nAturAl intestinAl infection. Adult BALB/c mice chAllenged with 10(7) S. flexneri orgAnisms developed A rApid inflAmmAtory response chArActerized by polymorphonucleAr cell infiltrAtion Around And within the bronchi And strong systemic interleukin 6 response. ImplAntAtion of hybridomA cells in the bAck of mice, resulting in the development of A myelomA tumor producing mIgA in the serum And subsequently secretory mIgA in locAl secretions, or direct intrAnAsAl AdministrAtion of these Antibodies, protected the AnimAls AgAinst subsequent intrAnAsAl chAllenge with S. flexneri serotype 5A. Absence of histopAthologicAl lesion And significAnt decreAse in bActeriAl loAd of the lungs And of systemic interleukin 6 response were the three mAjor criteriA of protection. This protection wAs shown to be serotype-specific And dependent on locAl concentrAtion of mIgA. These dAtA demonstrAte thAt mucosAl Antibodies directed AgAinst A single polysAcchAridic surfAce epitope of ShigellA cAn protect AgAinst the diseAse.
