Tandem antioxidant enzymes confer synergistic protective responses in experimental filariasis

2013 ◽  
Vol 88 (4) ◽  
pp. 402-410 ◽  
Author(s):  
P.R. Prince ◽  
J. Madhumathi ◽  
G. Anugraha ◽  
P.J. Jeyaprita ◽  
M.V.R. Reddy ◽  
...  
Keyword(s):  
Immune Responses ◽  
Redox Regulation ◽  
Protective Efficacy ◽  
Wuchereria Bancrofti ◽  
Parasite Clearance ◽  
Cross Reactivity ◽  
Host Responses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Helminth Parasites ◽  
Cellular Immune

AbstractHelminth parasites use antioxidant defence strategies for survival during oxidative stress due to free radicals in the host. Accordingly, tissue-dwelling filarial parasites counteract host responses by releasing a number of antioxidants. Targeting these redox regulation proteins together, would facilitate effective parasite clearance. Here, we report the combined effect of protective immune responses trigged by recombinant Wuchereria bancrofti thioredoxin (WbTRX) and thioredoxin peroxidase (WbTPX) in an experimental filarial model. The expression of WbTRX and WbTPX in different stages of the parasite and their cross-reactivity were analysed by enzyme-linked immunosorbent assay (ELISA). The immunogenicity of recombinant proteins and their protective efficacy were studied in animal models when immunized in single or cocktail mode. The antigens showed cross-reactive epitopes and induced high humoral and cellular immune responses in mice. Further, parasite challenge against Brugia malayi L3 larvae in Mastomyscoucha conferred significant protection of 57% and 62% against WbTRX and WbTPX respectively. The efficacy of L3 clearance was significantly higher (71%) (P <  0.001) when the antigens were immunized together, showing a synergistic effect in multiple-mode vaccination. Hence, the study suggests WbTRX and WbTPX to be attractive vaccine candidates when immunized together and provides a tandem block for parasite elimination in the control of lymphatic filariasis.

scholarly journals Acute Plasmodium chabaudi chabaudi Malaria Infection Induces Antibodies Which Bind to the Surfaces of Parasitized Erythrocytes and Promote Their Phagocytosis by Macrophages In Vitro

1998 ◽  
Vol 66 (9) ◽  
pp. 4080-4086 ◽  
Author(s):  
Maria M. Mota ◽  
K. Neil Brown ◽  
Anthony A. Holder ◽  
William Jarra
Keyword(s):  
Parasite Clearance ◽  
Enzyme Linked Immunosorbent Assay ◽  
Antibody Activity ◽  
Parasite Line ◽  
Primary Role ◽  
Plasmodium Chabaudi ◽  
Species Specific ◽  
Cellular Immune ◽  
Variant Line

ABSTRACT CBA/Ca mice infected with 5 × 104 Plasmodium chabaudi chabaudi AS-parasitized erythrocytes experience acute but self-limiting infections of relatively short duration. Parasitemia peaks (∼40% infected erythrocytes) on day 10 or 11 and is then partially resolved over the ensuing 5 to 6 days, a period referred to as crisis. How humoral and cellular immune mechanisms contribute to parasite killing and/or clearance during crisis is controversial. Humoral immunity might be parasite variant, line, or species specific, while cellular immune responses would be relatively less specific. For P. c. chabaudi AS, parasite clearance is largely species and line specific during this time, which suggests a primary role for antibody activity. Accordingly, acute-phase plasma (APP; taken fromP. c. chabaudi AS-infected mice at day 11 or 12 postinfection) was examined for the presence of parasite-specific antibody activity by enzyme-linked immunosorbent assay. Antibody binding to the surface of intact, live parasitized erythrocytes, particularly those containing mature (trophozoite and schizont) parasites, was demonstrated by immunofluorescence in APP and the immunoglobulin G (IgG)-containing fraction thereof. Unfractionated APP (from P. c. chabaudi AS-infected mice), as well as its IgG fraction, specifically mediated the opsonization and internalization of P. c. chabaudi AS-parasitized erythrocytes by macrophages in vitro. APP from another parasite line (P. c. chabaudi CB) did not mediate the same effect against P. c. chabaudi AS-parasitized erythrocytes. These results, which may represent one mechanism of parasite removal during crisis, are discussed in relation to the parasite variant, line, and species specificity of parasite clearance during this time.

scholarly journals Protective Efficacy of an Inactive Vaccine Based on the LY02 Isolate against AcuteHaemophilus parasuisInfection in Piglets

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xiao-Hua Li ◽  
Guo-Zhen Zhao ◽  
Long-Xin Qiu ◽  
Ai-Ling Dai ◽  
Wang-Wei Wu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Protective Immunity ◽  
Protective Efficacy ◽  
Haemophilus Parasuis ◽  
Fujian Province ◽  
Cellular Immune Responses ◽  
Glässer’S Disease ◽  
Potential Vaccine ◽  
Cellular Immune ◽  
Glasser's Disease

Haemophilus parasuiscan cause Glässer’s disease characterized by fibrinous polyserositis, polyarthritis, and meningitis. The current prevention of Glässer’s disease is mainly based on the inactive vaccines; however, the protective efficacy usually fails in heterogeneous or homologous challenges. Here, the predominant lineage ofH. parasuis(LY02 strain) in Fujian province, China, characterized as serovar 5, was used to evaluate the protective immunity against acuteH. parasuisinfection in piglets after inactivation. Following challenging withH. parasuis,only mild lesions in the pigs immunized with the killed vaccine were observed, whereas the typical symptoms of Glässer’s disease presented in the nonimmunized piglets. A strong IgG immune response was induced by the inactive vaccine. CD4+and CD8+T lymphocyte levels were increased, indicating the potent cellular immune responses were elicited. The significantly high levels of IL-2, IL-4, TGF-β, and IFN-γin sera from pigs immunized with this killed vaccine suggested that the mixed Th1 and Th2 immune responses were induced, associated with the high protection againstH. parasuisinfection compared to the nonimmunized animals. This study indicated that the inactivated LY02 strain ofH. parasuiscould serve as a potential vaccine candidate to prevent the prevalence ofH. parasuisin Fujian province, China.

scholarly journals Enhanced cellular immunity and systemic control of SHIV infection by combined parenteral and mucosal administration of a DNA prime MVA boost vaccine regimen

2004 ◽  
Vol 85 (8) ◽  
pp. 2407-2419 ◽  
Author(s):  
B. Mäkitalo ◽  
P. Lundholm ◽  
J. Hinkula ◽  
C. Nilsson ◽  
K. Karlén ◽  
...  
Keyword(s):  
Immune Responses ◽  
T Lymphocyte ◽  
Protective Efficacy ◽  
Viral Rna ◽  
Post Challenge ◽  
Cellular Immune Responses ◽  
Immunodeficiency Virus ◽  
Cellular Immune ◽  
Hiv 1 ◽  
Rna Levels

The immunogenicity and protective efficacy of a DNA and recombinant modified vaccinia Ankara (MVA) vaccine administered by two different routes were investigated. DNA expressing HIV-1 IIIB env, gag, RT, rev, tat and nef, and MVA expressing HIV-1 IIIB nef, tat and rev and simian immunodeficiency virus (SIV) macJ5 gag/pol and vaccinia HIV-1 env, were used as immunogens. Four cynomolgus macaques received DNA intramuscularly (i.m.) at month 0 and intrarectally (i.r.) and intra-orally (i.o.) at 2 months, followed by MVA i.m. at 4 months and i.r. and i.o. at 8 months. Another group of four monkeys received the same immunogens but only i.m.. Overall, stronger cellular immune responses measured by ELISPOT and T-cell proliferation assay were detected in the group primed i.m. and boosted mucosally. Following homologous intravenous simian-human immunodeficiency virus (SHIV) challenge, one of eight vaccinated animals was completely protected. This monkey, immunized i.m. and i.r.+i.o., exhibited the highest levels of HIV Env, Nef and Tat antibodies, high HIV Tat cytotoxic T-lymphocyte activity and T-lymphocyte proliferative responses to HIV Env. Four weeks post-challenge none of the monkeys immunized i.m. and i.r.+i.o., and only two out of four animals immunized i.m., demonstrated detectable plasma viral RNA levels. In contrast, all eight control animals had demonstrable plasma viral RNA levels 4 weeks post-challenge. Thus, stronger cellular immune responses and reduction of challenge virus burden were demonstrated in animals immunized i.m. as well as mucosally, compared with animals immunized i.m. only. The breadth and magnitude of the induced immune responses correlated with protective efficacy.

scholarly journals Ad26.COV2.S or BNT162b2 Boosting of BNT162b2 Vaccinated Individuals

2021 ◽  
Author(s):  
C. Sabrina Tan ◽  
Ai-ris Y. Collier ◽  
Jinyan Liu ◽  
Jingyou Yu ◽  
Huahua Wan ◽  
...  
Keyword(s):  
Immune Responses ◽  
Protective Efficacy ◽  
Cellular Immune Responses ◽  
Antibody Titers ◽  
Cellular Immune

ABSTRACTPrevious studies have reported that a third dose of the BNT162b2 (Pfizer) COVID-19 vaccine increased antibody titers and protective efficacy. Here we compare humoral and cellular immune responses in 65 individuals who were vaccinated with the BNT162b2 vaccine and were boosted after at least 6 months with either Ad26.COV2.S (Johnson & Johnson; N=41) or BNT162b2 (Pfizer; N=24).

scholarly journals Cross-Protection against Challenge with Puumala Virus after Immunization with Nucleocapsid Proteins from Different Hantaviruses

2002 ◽  
Vol 76 (13) ◽  
pp. 6669-6677 ◽  
Author(s):  
Cristina de Carvalho Nicacio ◽  
Marcelo Gonzalez Della Valle ◽  
Paula Padula ◽  
Ewa Björling ◽  
Alexander Plyusnin ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Immune Responses ◽  
Hemorrhagic Fever ◽  
Cross Reactivity ◽  
Cross Protection ◽  
Laboratory Animals ◽  
Homologous Protein ◽  
Humoral Responses ◽  
Cellular Immune

ABSTRACT Hantaviruses are rodent-borne agents that cause hemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome in humans. The nucleocapsid protein (N) is relatively conserved among hantaviruses and highly immunogenic in both laboratory animals and humans, and it has been shown to induce efficient protective immunity in animal models. To investigate the ability of recombinant N (rN) from different hantaviruses to elicit cross-protection, we immunized bank voles with rN from Puumala (PUUV), Topografov (TOPV), Andes (ANDV), and Dobrava (DOBV) viruses and subsequently challenged them with PUUV. All animals immunized with PUUV and TOPV rN were completely protected. In the group immunized with DOBV rN, 7 of 10 animals were protected, while only 3 of 8 animals were protected in the group immunized with ANDV rN, which is more closely related to PUUV rN than DOBV rN. Humoral and cellular immune responses after rN immunization were also investigated. The highest cross-reactive humoral responses against PUUV antigen were detected in sera from ANDV rN-immunized animals, followed by those from TOPV rN-immunized animals, and only very low antibody cross-reactivity was observed in sera from DOBV rN-immunized animals. In proliferation assays, T lymphocytes from animals immunized with all heterologous rNs were as efficiently recalled in vitro by PUUV rN as were T lymphocytes from animals immunized with homologous protein. In summary, this study has shown that hantavirus N can elicit cross-protective immune responses against PUUV, and the results suggest a more important role for the cellular arm of the immune response than for the humoral arm in cross-protection elicited by rN.

scholarly journals Differential Effects of Prior Exposure to Environmental Mycobacteria on Vaccination with Mycobacterium bovis BCG or a Recombinant BCG Strain Expressing RD1 Antigens

2005 ◽  
Vol 73 (4) ◽  
pp. 2190-2196 ◽  
Author(s):  
Caroline Demangel ◽  
Thierry Garnier ◽  
Ida Rosenkrands ◽  
Stewart T. Cole
Keyword(s):  
Immune Responses ◽  
Mycobacterium Bovis ◽  
Protective Efficacy ◽  
In Silico Analysis ◽  
Inhibitory Effect ◽  
Protective Antigens ◽  
Environmental Mycobacteria ◽  
Cellular Immune ◽  
The Impact ◽  
Recombinant Bcg

ABSTRACT In silico analysis reveals that most protective antigens expressed by the antituberculous vaccine Mycobacterium bovis BCG (BCG) are conserved in M. avium, supporting the hypothesis that exposure to environmental mycobacteria generates cross-reactive immune responses blocking BCG activity. We investigated the impact of sensitization with M. avium, M. scrofulaceum, or M. vaccae on the protective efficacy of a recombinant BCG strain expressing RD1 antigens (BCG::RD1), using a mouse model of experimental tuberculosis (TB). No evidence that the RD1-encoded antigens ESAT-6, CFP-10, and PPE68 were expressed by these environmental strains could be demonstrated by Western blot analysis. Mice sensitized with each of these strains did not prime cellular immune responses cross-reacting with the immunodominant ESAT-6. Importantly, clearance of BCG::RD1 from the lungs and spleens of mice exposed to each of the environmental strains before vaccination was minimal compared to that of BCG. In mice sensitized with M. avium, increased persistence of BCG::RD1 correlated with stronger antimycobacterial gamma interferon responses and enhanced protection against aerosol infection with M. tuberculosis, compared to BCG. In contrast, animals exposed to M. scrofulaceum or M. vaccae prior to vaccination with BCG or BCG::RD1 were better protected against TB than were the unsensitized controls. Our results suggest that the inhibitory effect of environmental mycobacteria on the protective efficacy of BCG depends critically on the extent of cross-recognition of antigens shared with the vaccine. In hosts sensitized with M. avium, potent immunogenicity of ESAT-6 and increased persistence of BCG::RD1 may allow this recombinant vaccine to overcome preexisting antimycobacterial responses.

scholarly journals Cellular Immune Responses to Recombinant Mycobacterium bovis BCG Constructs Expressing Major Antigens of Region of Difference 1 of Mycobacterium tuberculosis

2013 ◽  
Vol 20 (8) ◽  
pp. 1230-1237 ◽  
Author(s):  
Kholoud Shaban ◽  
Hanady A. Amoudy ◽  
Abu S. Mustafa
Keyword(s):  
Immune Responses ◽  
Mycobacterium Bovis ◽  
Protective Efficacy ◽  
Spleen Cells ◽  
T Helper 1 ◽  
Th1 Cell ◽  
Content Type ◽  
Cellular Immune Responses ◽  
Ifn Γ ◽  
Cellular Immune

ABSTRACTBesides being the most widely used vaccine directed against tuberculosis (TB) worldwide,Mycobacterium bovisBCG is also the most controversial vaccine in current use. Its protective efficacy varies widely in different parts of the world. One approach to improving the current BCG vaccine might be to produce recombinant BCG strains that express major antigens encoded by genes that are present in theM. tuberculosis-specific region of difference 1 (RD1), such aspe35,cfp10, andesat6. In this study,pe35,cfp10, andesat6genes were cloned into shuttle plasmid pDE22 to generate the recombinant plasmids PDE22-PE35, PDE22-CFP10, and PDE22-ESAT6, which were electroporated into BCG to generate recombinant BCGs (rBCGs). The cellular immune responses (antigen-induced proliferation and secretion of selected T helper 1 [Th1], Th2, and anti-inflammatory cytokines, i.e., gamma interferon [IFN-γ], interleukin 5 [IL-5], and IL-10, respectively) that are specific to the proteins of cloned genes were studied by using spleen cells from mice immunized with native BCGs and rBCGs and synthetic peptides covering the protein sequence of the cloned genes. The results showed that the spleen cells did not secrete IL-5, whereas IL-10 was secreted in response to peptides of all three proteins from mice immunized with rBCGs only, suggesting expression of the cloned genes andin vivopriming of spleen cells to the expressed proteins. However, in Th1 cell assays that correlate with protective cellular immune responses, i.e., antigen-induced proliferation and IFN-γ secretion, only mice immunized with rBCG-pDE22-PE35 yielded positive responses to the peptides of PE35. These results suggest that rBCG-PDE22-PE35 is the only one of the three vaccines used in this work that is worthy of consideration as a new vaccine candidate against TB.

scholarly journals Stimulation of Dendritic Cells via CD40 Enhances Immune Responses to Mycobacterium tuberculosisInfection

2001 ◽  
Vol 69 (4) ◽  
pp. 2456-2461 ◽  
Author(s):  
Caroline Demangel ◽  
Umaimainthan Palendira ◽  
Carl G. Feng ◽  
Andrew W. Heath ◽  
Andrew G. D. Bean ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Protective Efficacy ◽  
Interleukin 12 ◽  
Ifn Γ ◽  
Cellular Immune ◽  
Stimulation Of

ABSTRACT The resolution of pulmonary tuberculosis (TB) critically depends on the development of the Th1 type of immune responses, as exemplified by the exacerbation of TB in IL-12-deficient mice. Therefore, vaccination strategies optimizing IL-12 production by antigen-presenting cells (APC) in response to mycobacteria may have enhanced protective efficacy. Since dendritic cells (DC) are the critical APC for activation of CD4+ and CD8+ T cells, we examined whether stimulation of Mycobacterium bovis bacillus Calmette Guérin (BCG)-infected DC via CD40 increased their ability to generate Th1-oriented cellular immune responses. Incubation of DC with an agonistic anti-CD40 antibody activated CD40 signaling in DC, as shown by increased expression of major histocompatibility complex class II and costimulatory molecules, mRNA production for proinflammatory cytokines and interleukin 12 (IL-12) p40. This activation pattern was maintained when DC were stimulated with anti-CD40 antibody and infected with BCG. Importantly, CD40-stimulated BCG-infected DC displayed increased capacity to release bioactive IL-12 and to activate gamma interferon (IFN-γ) producing T cells in vitro. Moreover, when C57BL/6 mice were immunized with these DC and challenged with aerosol Mycobacterium tuberculosis, increased levels of mRNA for IL-12 p40, IL-18, and IFN-γ were present in the draining mediastinal lymph nodes. However, the mycobacterial burden in the lungs was not reduced compared to that in mice immunized with BCG-infected non-CD40-stimulated DC. Therefore, although the manipulation of DC via CD40 is effective for enhancing immune responses to mycobacteria in vivo, additional strategies are required to increase protection against virulent M. tuberculosis infection.

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