scholarly journals Overcoming Immunity to a Viral Vaccine by DNA Priming before Vector Boosting

2003 ◽  
Vol 77 (1) ◽  
pp. 799-803 ◽  
Author(s):  
Zhi-yong Yang ◽  
Linda S. Wyatt ◽  
Wing-pui Kong ◽  
Zoe Moodie ◽  
Bernard Moss ◽  
...  
Keyword(s):  
Immune Responses ◽  
Viral Vectors ◽  
Ebola Virus ◽  
Viral Vector ◽  
Hemorrhagic Fever ◽  
Viral Immunity ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Viral Vaccine ◽  
Humoral Responses

ABSTRACT Replication-defective adenovirus (ADV) and poxvirus vectors have shown potential as vaccines for pathogens such as Ebola or human immunodeficiency virus in nonhuman primates, but prior immunity to the viral vector in humans may limit their clinical efficacy. To overcome this limitation, the effect of prior viral exposure on immune responses to Ebola virus glycoprotein (GP), shown previously to protect against lethal hemorrhagic fever in animals, was studied. Prior exposure to ADV substantially reduced the cellular and humoral immune responses to GP expressed by ADV, while exposure to vaccinia inhibited vaccine-induced cellular but not humoral responses to GP expressed by vaccinia. This inhibition was largely overcome by priming with a DNA expression vector before boosting with the viral vector. Though heterologous viral vectors for priming and boosting can also overcome this effect, the paucity of such clinical viral vectors may limit their use. In summary, it is possible to counteract prior viral immunity by priming with a nonviral, DNA vaccine.

scholarly journals Humoral Immune Responses against the Mycobacteriumtuberculosis 38-Kilodalton, MTB48, and CFP-10/ESAT-6 Antigens in Tuberculosis

2010 ◽  
Vol 17 (3) ◽  
pp. 372-375 ◽  
Author(s):  
Xueqiong Wu ◽  
Yourong Yang ◽  
Junxian Zhang ◽  
Bangying Li ◽  
Yan Liang ◽  
...  
Keyword(s):  
Immune Responses ◽  
Healthy Subjects ◽  
Enzyme Linked Immunosorbent Assay ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Single Antigen ◽  
Human Sera ◽  
Low Sensitivity ◽  
Humoral Responses ◽  
Culture Negative

ABSTRACT The diagnosis of smear-negative and culture-negative patients with active tuberculosis (TB) is challenging. The detection of Mycobacterium tuberculosis-specific antibodies in human sera has been an important diagnostic aid. However, detection of antibody responses to a single antigen usually has a low sensitivity for diagnosis of TB. In this study, humoral immune responses against recombinant M. tuberculosis 38-kDa, MTB48, and CFP-10/ESAT-6 (culture filtrate protein 10/6-kDa early secreted antigen target of M. tuberculosis) antigens in 250 Chinese TB patients and 260 healthy subjects were evaluated by an enzyme-linked immunosorbent assay (ELISA). The levels of antibodies against those antigens in TB patients, even in bacterium-negative ones, were significantly higher than those in healthy subjects (P < 0.001). The serodiagnostic sensitivities to detect antibodies against individual antigens, i.e., recombinant M. tuberculosis 38-kDa, MTB48, and CFP-10/ESAT-6 antigens, in TB patients were 73.6%, 73.2%, and 60.4%, respectively, with specificities of 85.4%, 77.7%, and 73.8%, respectively. Importantly, the sensitivity to positively detect humoral responses to one of the antigens increased further. Our data suggest that the humoral immune responses to M. tuberculosis antigens in TB patients are heterogeneous. The 38-kDa, MTB48, and CFP-10/ESAT-6 antigens can be used as the cocktail antigens in the serodiagnosis of active TB, especially for smear- or culture-negative TB cases.

scholarly journals Longitudinal immune dynamics of mild COVID-19 define signatures of recovery and persistence

2021 ◽  
Author(s):  
Aarthi Talla ◽  
Suhas V Vasaikar ◽  
Maria P Lemos ◽  
Zoe Moodie ◽  
Mark-Phillip Lee Pebworth ◽  
...  
Keyword(s):  
Immune Responses ◽  
Acute Infection ◽  
Early Time ◽  
Chromatin Accessibility ◽  
Outpatient Setting ◽  
Correlated Data ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Serum Proteomics ◽  
Humoral Responses

SARS-CoV-2 has infected over 160 million and caused more than 3 million deaths to date. Most individuals (>80%) have mild symptoms and recover in the outpatient setting, but detailed studies of immune responses have focused primarily on moderate to severe COVID-19. We deeply profiled the longitudinal immune response in individuals with mild COVID beginning with early time points post-infection (1-15 days) and proceeding through convalescence to >100 days after symptom onset. We correlated data from single cell analyses of peripheral blood cells, serum proteomics, virus-specific cellular and humoral immune responses, and clinical metadata. Acute infection was characterized by vigorous coordinated innate and adaptive activation, including an early cellular and proteomic signature that correlated with the amplitude of virus-specific humoral responses after day 30. We characterized signals associated with recovery and convalescence to define a new signature of inflammatory cytokines, gene expression, and chromatin accessibility that persists in individuals with post-acute sequelae of SARS-CoV-2 infection (PASC).

scholarly journals Strong humoral immune responses against SARS-CoV-2 Spike after BNT162b2 mRNA vaccination with a sixteen-week interval between doses

2021 ◽  
Author(s):  
Alexandra Tauzin ◽  
Shang Yu Gong ◽  
Guillaume Beaudoin-Bussieres ◽  
Dani Vezina ◽  
Romain Gasser ◽  
...  
Keyword(s):  
Public Health ◽  
Immune Responses ◽  
Vaccine Efficacy ◽  
Standard Regimen ◽  
Effector Functions ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Health Authorities ◽  
Public Health Authorities ◽  
Humoral Responses

While the standard regimen of the BNT162b2 mRNA vaccine includes two doses administered three weeks apart, some public health authorities decided to space them, raising concerns about vaccine efficacy. Here, we analyzed longitudinal humoral responses including antibody binding, Fc-mediated effector functions and neutralizing activity against the D614G strain but also variants of concern and SARS-CoV-1 in a cohort of SARS-CoV-2 naive and previously infected individuals, with an interval of sixteen weeks between the two doses. While the administration of a second dose to previously infected individuals did not significantly improve humoral responses, we observed a significant increase of humoral responses in naive individuals after the 16-weeks delayed second shot, achieving similar levels as in previously infected individuals. Our results highlight strong vaccine-elicited humoral responses with an extended interval BNT162b2 vaccination for naive individuals.

scholarly journals A Bivalent, Spherical Virus-Like Particle Vaccine Enhances Breadth of Immune Responses against Pathogenic Ebola Viruses in Rhesus Macaques

2020 ◽  
Vol 94 (9) ◽  
Author(s):  
Karnail Singh ◽  
Bishal Marasini ◽  
Xuemin Chen ◽  
Lingmei Ding ◽  
Jaang-Jiun Wang ◽  
...  
Keyword(s):  
Immune Responses ◽  
Neutralizing Antibodies ◽  
Ebola Virus ◽  
Vaccine Development ◽  
Rhesus Macaques ◽  
Pathogenic Species ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Novel Approach ◽  
Virus Like Particle

ABSTRACT The 2013–2016 Ebola outbreak in West Africa led to accelerated efforts to develop vaccines against these highly virulent viruses. A live, recombinant vesicular stomatitis virus-based vaccine has been deployed in outbreak settings and appears highly effective. Vaccines based on replication-deficient adenovirus vectors either alone or in combination with a multivalent modified vaccinia Ankara (MVA) Ebola vaccine also appear promising and are progressing in clinical evaluation. However, the ability of current live vector-based approaches to protect against multiple pathogenic species of Ebola is not yet established, and eliciting durable responses may require additional booster vaccinations. Here, we report the development of a bivalent, spherical Ebola virus-like particle (VLP) vaccine that incorporates glycoproteins (GPs) from Zaire Ebola virus (EBOV) and Sudan Ebola virus (SUDV) and is designed to extend the breadth of immunity beyond EBOV. Immunization of rabbits with bivalent Ebola VLPs produced antibodies that neutralized all four pathogenic species of Ebola viruses and elicited antibody-dependent cell-mediated cytotoxicity (ADCC) responses against EBOV and SUDV. Vaccination of rhesus macaques with bivalent VLPs generated strong humoral immune responses, including high titers of binding, as well as neutralizing antibodies and ADCC responses. VLP vaccination led to a significant increase in the frequency of Ebola GP-specific CD4 and CD8 T cell responses. These results demonstrate that a novel bivalent Ebola VLP vaccine elicits strong humoral and cellular immune responses against pathogenic Ebola viruses and support further evaluation of this approach as a potential addition to Ebola vaccine development efforts. IMPORTANCE Ebola outbreaks result in significant morbidity and mortality in affected countries. Although several leading candidate Ebola vaccines have been developed and advanced in clinical testing, additional vaccine candidates may be needed to provide protection against different Ebola species and to extend the durability of protection. A novel approach demonstrated here is to express two genetically diverse glycoproteins on a spherical core, generating a vaccine that can broaden immune responses against known pathogenic Ebola viruses. This approach provides a new method to broaden and potentially extend protective immune responses against Ebola viruses.

Optimization of Expression and Purification of Recombinant Mouse plac1

2022 ◽  
Author(s):  
Shaghayegh Rahdan ◽  
Seyed Alireza Razavi ◽  
Mahboobeh Nazari ◽  
Sorour Shojaeian ◽  
Fazel Shokri ◽  
...  
Keyword(s):  
Immune Responses ◽  
Recombinant Proteins ◽  
Culture Medium ◽  
Ectopic Expression ◽  
Expression And Purification ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Wide Range ◽  
Humoral Responses ◽  
And Control

Background: Placenta-specific 1 (PLAC1) is one of the recently-discovered Cancer-Testis-Placenta (CTP) antigen with restricted normal tissue and ectopic expression in a wide range of cancer cells from different histological origins. The production of recombinant human PLAC1 has already been optimized; however, no study has been reported so far on the production and purification of mouse plac1. In this study, mouse plac1 expression and purification was optimized in a prokaryotic system and the effects of the generated proteins on inducing humoral responses in mice were investigated. Methods: A fusion protein containing full extracellular domain of mouse plac1, immunostimulatory peptides, tetanus toxin P2P30 and PADRE and KDEL3 signal (main plac1), and the same fragment without immunostimulatory peptides (control plac1) was produced. To optimize production and purification steps, different parameters including bacterial strain, cultivation temperature, cultivation time, IPTG concentration, culture medium, and also different buffers for purification of the recombinant proteins were tested. After confirming the identity of recombinant plac1 proteins with Western Blotting (WB) and ELISA assays, these proteins were subcutaneously injected in mice with Freund's adjuvant and the anti-plac1 antibody response was detected by ELISA. Results: The optimal expression level of main and control plac1 was obtained in BL21 (DE3) and TB culture medium in the presence of 0.25 mM IPTG after 24 hr of induction at 15°C. The buffer containing 2% sarkosyl produced higher yield and purity. Our results showed specific reactivity of anti-human recombinant plac1 polyclonal antibody with both main and control plac1 recombinant proteins in WB and ELISA analysis. Both proteins induced humoral responses in mice; however, anti-plac1  antibody titer was significantly higher in sera of mice immunized with main compared to control plac1. Conclusion: In this study, an optimized protocol for production and purification of mouse plac1 was reported and it was shown that insertion of immunostimulatory peptides in gene construct could efficiently enhance humoral immune responses against mouse plac1, which could potentially augment cellular immune responses against plac1 leading to more effective anti-cancer responses.

scholarly journals Humoral Immune Responses of Tuberculosis Patients in Brazil Indicate Recognition of Mycobacterium tuberculosis MPT-51 and GlcB

2008 ◽  
Vol 15 (3) ◽  
pp. 579-581 ◽  
Author(s):  
Cristina Melo Cardoso Almeida ◽  
Arioldo C. Vasconcelos ◽  
André Kipnis ◽  
Ana Lúcia Andrade ◽  
Ana Paula Junqueira-Kipnis
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Immune Responses ◽  
Immunosorbent Assay ◽  
Immunoglobulin M ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tuberculosis Patients ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Humoral Responses

ABSTRACT The humoral responses to recombinant MPT-51 and GlcB was determined by using an enzyme-linked immunosorbent assay. Levels of immunoglobulin M (IgM) against MPT-51 and IgG against GlcB were higher among tuberculosis (TB) patients than among control individuals. When the MPT-51 and GlcB assays were combined, 90.8% specificity and 75.5% sensitivity were observed. MPT-51 and GlcB were recognized in the humoral responses of Brazilian TB patients.

scholarly journals Immune responses in mice induced by multi-epitope DNA vaccine and protein vaccine of Crimean-Congo Hemorrhagic Fever Virus

2019 ◽  
Author(s):  
Meilipaiti Yusufu ◽  
Alai Shalitanati ◽  
Huan Yu ◽  
Abulimiti Moming ◽  
Yijie Li ◽  
...  
Keyword(s):  
Immune Responses ◽  
Dna Vaccine ◽  
Hemorrhagic Fever ◽  
Control Group ◽  
Protein Vaccine ◽  
Crimean Congo Hemorrhagic Fever ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Significant Difference ◽  
Double Copy

AbstractCrimean-Congo Hemorrhagic Fever (CCHF), caused by the CCHF virus (CCHFV), is a severe tick borne zoonosis widely distributed in over 30 countries and regions. Currently, there is no licensed vaccine available for CCHF in China. To evaluate the cellular and humoral immune responses induced by multi-epitope DNA and protein vaccine of CCHF in BALB/c mice, a multi-epitope gene (MEPX) segment with tandem including six highly conservative and immunedominant B cell epitopes was designed based on the analysis of hydrophilicity and antigenic determinant sites in amino acid sequences of nucleoprotein and glycoprotein from CCHFV strain YL04057. The single and double-copy multi-epitope gene (MEPX and MEPX2) were respectively cloned into the eukaryotic expression vector pVAX I to construct the recombinant (r) plasmid pVAX-MEPX and pVAX-MEPX2 as DNA vaccines. The results of immunofluorescence in vitro showed that the pVAX-MEPX and pVAX-MEPX2 could be expressed in 293T cells. The recombinant prokaryotic plasmid pET-32a-MEPX and pET-32a-MEPX2 constructed previously were transformed them into E. coli BL21 (DE3), and recombinant multi-epitope proteins (rMEPX and rMEPX2) were obtained and purificated by Nickel affinity chromatography. Western blot results showed that rMEPX and rMEPX2 had good antigenicity. BALB/c mice were immunized with DNA vaccine alone, protein vaccine alone, and DNA prime followed by recombinant protein boost immunization strategy, respectively. After three immunizations, MTT assay, cytokine content assay, and ELISA assay for antibody titers were used to evaluate the immune response. The proliferation of mouse specific T lymphocytes in the enhanced by pVAX-MEPX2 combined with rMEPX2 boosting group was significant, and the expression levels of serum IFN-γ and IL-4 in mice were as high as 118.67 pg/mL and 135.33 pg/mL with significant difference compared to the control group (p<0.01), and serum antibody titer could reach up to 4.1×105. Double-copy multi-epitope vaccines groups (pVAX-MEPX2+ rMEPX2) generated better cellular and humoral immune responses by DNA prime-protein vaccine boost combinatorial immunization. This result could lay the foundation for the development of CCHFV multi-epitope vaccine candidates.

scholarly journals Humoral Responses and Serological Assays in SARS-CoV-2 Infections

2020 ◽  
Vol 11 ◽  
Author(s):  
Yannick Galipeau ◽  
Matthew Greig ◽  
George Liu ◽  
Matt Driedger ◽  
Marc-André Langlois
Keyword(s):  
Immune Responses ◽  
Vaccine Development ◽  
Cross Reactivity ◽  
The Novel ◽  
Epidemiological Models ◽  
Humoral Immune ◽  
Health Measures ◽  
Humoral Immune Responses ◽  
Humoral Responses ◽  
Vaccination Campaigns

In December 2019, the novel betacoronavirus Severe Acute Respiratory Disease Coronavirus 2 (SARS-CoV-2) was first detected in Wuhan, China. SARS-CoV-2 has since become a pandemic virus resulting in hundreds of thousands of deaths and deep socioeconomic implications worldwide. In recent months, efforts have been directed towards detecting, tracking, and better understanding human humoral responses to SARS-CoV-2 infection. It has become critical to develop robust and reliable serological assays to characterize the abundance, neutralization efficiency, and duration of antibodies in virus-exposed individuals. Here we review the latest knowledge on humoral immune responses to SARS-CoV-2 infection, along with the benefits and limitations of currently available commercial and laboratory-based serological assays. We also highlight important serological considerations, such as antibody expression levels, stability and neutralization dynamics, as well as cross-reactivity and possible immunological back-boosting by seasonal coronaviruses. The ability to accurately detect, measure and characterize the various antibodies specific to SARS-CoV-2 is necessary for vaccine development, manage risk and exposure for healthcare and at-risk workers, and for monitoring reinfections with genetic variants and new strains of the virus. Having a thorough understanding of the benefits and cautions of standardized serological testing at a community level remains critically important in the design and implementation of future vaccination campaigns, epidemiological models of immunity, and public health measures that rely heavily on up-to-date knowledge of transmission dynamics.

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