scholarly journals Type IVB Pilus Operon Promoter Controlling Expression of the Severe Acute Respiratory Syndrome-Associated Coronavirus Nucleocapsid Gene in Salmonella enterica Serovar Typhi Elicits Full Immune Response by Intranasal Vaccination

2007 ◽  
Vol 14 (8) ◽  
pp. 990-997 ◽  
Author(s):  
Fengling Luo ◽  
Yong Feng ◽  
Min Liu ◽  
Pingfei Li ◽  
Qin Pan ◽  
...  

ABSTRACT Attenuated Salmonella enterica serovar Typhi strains have been considered to be attractive as potential live oral delivery vector vaccines because of their ability to elicit the full array of immune responses in humans. In this study, we constructed an attenuated S. enterica serovar Typhi strain stably expressing conserved nucleocapsid (N) protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) by integrating the N gene into the pilV gene, which was under the control of the type IVB pilus operon promoter in S. enterica serovar Typhi. BALB/c mice were immunized with this recombinant strain through different routes: intranasally, orogastrically, intraperitoneally, and intravenously. Results showed that the intranasal route caused the highest production of specific immunoglobulin G (IgG), IgG2a, and secretory IgA, where IgG2a was imprinted as a Th1 cell bias. Moreover, this recombinant live vaccine induced significantly high levels of specific cytotoxic T-lymphocyte activities and increased gamma interferon-producing T cells compared with the parental strain. Our work provides insights into how the type IVB pilus operon promoter controlling SARS-CoV N gene expression in Salmonella might be attractive for a live-vector vaccine against SRAS-CoV infection, for it could induce mucosal, humoral, and cellular immune responses. Our work also indicates that the type IVB pilus operon promoter controlling foreign gene expression in Salmonella can elicit full immune responses by intranasal vaccination.

2014 ◽  
Vol 21 (6) ◽  
pp. 799-807 ◽  
Author(s):  
Chetan V. Jawale ◽  
John Hwa Lee

ABSTRACTTheEscherichia coliheat-labile enterotoxin B subunit (LTB) is a potent vaccine adjuvant.Salmonella entericaserovar Enteritidis ghosts carrying LTB (S. Enteritidis-LTB ghosts) were genetically constructed using a novel plasmid, pJHL187-LTB, designed for the coexpression of the LTB and E lysis proteins.S. Enteritidis-LTB ghosts were characterized using scanning electron microscopy to visualize their transmembrane tunnel structures. The expression of LTB inS. Enteritidis-LTB ghost preparations was confirmed by immunoblot and enzyme-linked immunosorbent assays. The parenteral adjuvant activity of LTB was demonstrated by immunizing chickens with eitherS. Enteritidis-LTB ghosts orS. Enteritidis ghosts. Chickens were intramuscularly primed at 5 weeks of age and subsequently boosted at 8 weeks of age. In total, 60 chickens were equally divided into three groups (n= 20 for each): group A, nonvaccinated control; group B, immunized withS. Enteritidis-LTB ghosts; and group C, immunized withS. Enteritidis ghosts. Compared with the nonimmunized chickens (group A), the immunized chickens (groups B and C) exhibited increased titers of plasma IgG and intestinal secretory IgA antibodies. The CD3+CD4+subpopulation of T cells was also significantly increased in both immunized groups. Among the immunized chickens, those in group B exhibited significantly increased titers of specific plasma IgG and intestinal secretory IgA (sIgA) antibodies compared with those in group C, indicating the immunomodulatory effects of the LTB adjuvant. Furthermore, both immunized groups exhibited decreased bacterial loads in their feces and internal organs. These results indicate that parenteral immunization withS. Enteritidis-LTB ghosts can stimulate superior induction of systemic and mucosal immune responses compared to immunization withS. Enteritidis ghosts alone, thus conferring efficient protection against salmonellosis.


2008 ◽  
Vol 76 (5) ◽  
pp. 1940-1951 ◽  
Author(s):  
Hakim Echchannaoui ◽  
Matteo Bianchi ◽  
David Baud ◽  
Martine Bobst ◽  
Jean-Christophe Stehle ◽  
...  

ABSTRACT Cervical cancer, the second leading cause of cancer deaths in women, is the consequence of high-risk human papillomavirus (HPV) infections. Toward the development of therapeutic vaccines that can induce both innate and adaptive mucosal immune responses, we analyzed intravaginal (ivag) vaccine delivery of live attenuated Salmonella enterica serovar Typhimurium expressing HPV16L1 as a model antigen. Innate immune responses were examined in cervicovaginal tissues by determining gene expression patterns by microarray analysis using nylon membranes imprinted with cDNA fragments coding for inflammation-associated genes. At 24 h, a wide range of genes, including those for chemokines and Th1- and Th2-type cytokine and chemokine receptors were up-regulated in mice ivag immunized with Salmonella compared to control mice. However, the majority of transcripts returned to their steady-state levels 1 week after immunization, suggesting a transient inflammatory response. Indeed, cervicovaginal histology of immunized mice showed a massive, but transient, infiltration of macrophages and neutrophils, while T cells were still increased after 7 days. Ivag immunization also induced humoral and antitumor immune responses, i.e., serum and vaginal anti-HPV16VLP antibody titers similar to those induced by oral immunization, and significant protection in tumor protection experiments using HPV16-expressing C3 tumor cells. These results show that ivag immunization with live attenuated Salmonella expressing HPV16 antigens modulates the local mucosal gene expression pattern into a transient proinflammatory profile, elicits strong systemic and mucosal immunity against HPV16, and confers protection against HPV16 tumor cells subcutaneously implanted in mice. Examination of the efficacy with which ivag HPV16E7E6 Salmonella induces regression of tumors located in cervicovaginal tissue is warranted.


2021 ◽  
Author(s):  
Kaori Sano ◽  
Disha Bhavsar ◽  
Gagandeep Singh ◽  
Daniel Floda ◽  
Komal Srivastava ◽  
...  

AbstractMucosal immune responses are critical to prevent respiratory infections but it is unclear to what extent antigen specific mucosal secretory IgA (SIgA) antibodies are induced by mRNA vaccination in humans. We analyzed, therefore, paired serum and saliva samples from study participants with and without COVID-19 at multiple timepoints before and after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination. Our results suggest that the level of mucosal SIgA responses induced by mRNA vaccination depend on pre-existing immunity. Indeed, vaccination induced only a weak mucosal SIgA response in individuals without pre-existing mucosal antibody responses to SARS-CoV-2 while SIgA induction after vaccination was efficient in COVID-19 survivors. Our data indicate that vaccinated seropositive individuals were able to swiftly induce relatively high anti-spike SIgA responses by boosting pre-existing mucosal immunity. In contrast, seronegative individuals did not have pre-existing anti-SARS-CoV-2 or cross-reacting anti-HCoV SIgA antibodies prior to vaccination, and, thus, little or no anti-SARS-CoV-2 SIgA antibodies were induced by vaccination in these individuals.


2011 ◽  
Vol 18 (7) ◽  
pp. 1041-1045 ◽  
Author(s):  
Hongmei Jiao ◽  
Zhiming Pan ◽  
Yuelan Yin ◽  
Shizhong Geng ◽  
Lin Sun ◽  
...  

ABSTRACTSeveral studies have reported that intramuscular injection of DNA vaccines against infectious bronchitis virus (IBV) induces protective immune responses. In the present study, we developed oral and nasal DNA vaccines that carried the S1 gene and N gene of IBV delivered by attenuatedSalmonella entericaserovar Typhimurium strains SL/pV-S1 and SL/pV-N, respectively. The safety and stability of recombinantSalmonellavaccine were evaluated. Following oral and nasal administration to chickens, the serum and mucosal samples were collected and antibodies against IBV were measured. Chickens were then challenged with IBV strain M41 by the nasal-ocular route 3 weeks after boosting. The results showed that oral and nasal immunization with coadministered SL/pV-S1 and SL/pV-N elicited significant IBV-specific humoral and mucosal immune responses and conferred protective efficacy against IBV challenge higher than that in chickens immunized only with SL/pV-S1. The current study shows that novel DNA vaccines delivered by attenuatedS.Typhimurium may be promising candidates for the prevention of infectious bronchitis (IB).These vaccines are efficacious, easily produced economically, and able to be delivered orally and nasally rather than injected. Coadministration of SL/pV-S1 and SL/pV-N may represent an effective mucosal vaccination regimen.


2009 ◽  
Vol 2009 (2) ◽  
pp. 206-212 ◽  
Author(s):  
Xiu-Mei SHENG ◽  
Xin-Xiang HUANG ◽  
Ling-Xiang MAO ◽  
Chao-Wang ZHU ◽  
Shun-Gao XU ◽  
...  

2020 ◽  
Vol 27 (20) ◽  
pp. 3330-3345
Author(s):  
Ana G. Rodríguez-Hernández ◽  
Rafael Vazquez-Duhalt ◽  
Alejandro Huerta-Saquero

Nanomaterials have become part of our daily lives, particularly nanoparticles contained in food, water, cosmetics, additives and textiles. Nanoparticles interact with organisms at the cellular level. The cell membrane is the first protective barrier against the potential toxic effect of nanoparticles. This first contact, including the interaction between the cell membranes -and associated proteins- and the nanoparticles is critically reviewed here. Nanoparticles, depending on their toxicity, can cause cellular physiology alterations, such as a disruption in cell signaling or changes in gene expression and they can trigger immune responses and even apoptosis. Additionally, the fundamental thermodynamics behind the nanoparticle-membrane and nanoparticle-proteins-membrane interactions are discussed. The analysis is intended to increase our insight into the mechanisms involved in these interactions. Finally, consequences are reviewed and discussed.


1988 ◽  
Vol 263 (28) ◽  
pp. 13983-13986
Author(s):  
P R Dobner ◽  
A S Tischler ◽  
Y C Lee ◽  
S R Bloom ◽  
S R Donahue
Keyword(s):  
N Gene ◽  

2021 ◽  
Vol 22 (3) ◽  
pp. 1118
Author(s):  
Abdulaziz Alamri ◽  
Derek Fisk ◽  
Deepak Upreti ◽  
Sam K. P. Kung

Dendritic cells (DC) connect the innate and adaptive arms of the immune system and carry out numerous roles that are significant in the context of viral disease. Their functions include the control of inflammatory responses, the promotion of tolerance, cross-presentation, immune cell recruitment and the production of antiviral cytokines. Based primarily on the available literature that characterizes the behaviour of many DC subsets during Severe acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19), we speculated possible mechanisms through which DC could contribute to COVID-19 immune responses, such as dissemination of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to lymph nodes, mounting dysfunctional inteferon responses and T cell immunity in patients. We highlighted gaps of knowledge in our understanding of DC in COVID-19 pathogenesis and discussed current pre-clinical development of therapies for COVID-19.


Sign in / Sign up

Export Citation Format

Share Document