Systemic immune response of gnotobiotic mice infected with porcine circovirus type 2 after administration of Lactobacillus reuteri L26 Biocenol™

2018 ◽  
Vol 9 (6) ◽  
pp. 951-961
Author(s):  
D. Mudroňová ◽  
V. Karaffová ◽  
T. Csank ◽  
J. Király ◽  
V. Revajová ◽  
...  

In our previous study we confirmed an antiviral activity of probiotic Lactobacillus reuteri L26 which was mediated by stimulation of local intestinal immunity. The aim of this paper was to evaluate the influence of L. reuteri L26 on the systemic immune response in gnotobiotic mice infected with porcine circovirus type 2 (PCV2). A total of 30 germ-free mice were divided into 3 groups and animals in noninfected and infected control groups (NC and IC; n=10) received sterile de Man-Rogosa-Sharpe broth for 7 days and animals in experimental group L+PCV (n=10) were inoculated with L. reuteri L26. Subsequently, mice in L+PCV and IC groups were infected with PCV2; however, mice in the control group received virus cultivation medium (mock). The results showed an increase of percentage of cytotoxic cells (CD8+ and CD49b+CD8-) and oxidative burst of phagocytes, up-regulation of the gene expression of RANTES, granulocyte-macrophage colony-stimulating factor, interferon-γ and immunoglobulin A in blood above all in the later phase of infection (14 dpi) in L+PCV group accompanied by higher load of PCV2 in the serum. These findings indicate that L. reuteri L26 has a potential to induce systemic immune reaction, but in gnotobiotic mice immune stimulation can increase virus replication.

2017 ◽  
Vol 8 (3) ◽  
pp. 367-378 ◽  
Author(s):  
V. Karaffová ◽  
T. Csank ◽  
D. Mudroňová ◽  
J. Király ◽  
V. Revajová ◽  
...  

Probiotic bacteria are frequently used for prevention of bacterial infections of the gastrointestinal tract, but there are only limited studies on their efficacy against viral gut infections in animals. The aim of this study was to investigate the effect of probiotic Lactobacillus reuteri L26 BiocenolTM on the innate and adaptive immune responses in germ-free Balb/c mice, experimentally infected by porcine circovirus type 2 (PCV2), which confers immunosuppressive effect. A total of 30 six-week-old female mice were divided into 3 groups and animals in experimental group LPCV (n=10) were inoculated with L. reuteri L26, animals in the control group (C; n=10) and experimental group PCV (n=10) received sterile De Man-Rogosa-Sharpe broth for 7 days. Subsequently, mice from both experimental groups were infected with PCV2; however, mice in the control group received virus cultivation medium (mock). Virus load in faeces, ileum and mesenteric lymph nodes (MLN); as well as gene expression of selected cytokines, immunoglobulin A (IgA) and polymeric Ig receptor (PIgR) in the ileum, and percentage of CD8+, CD19+ and CD49b+CD8- cells in the MLN were evaluated. Our results showed that L. reuteri significantly decreased the amount of PCV2 in faeces and in the ileum, and up-regulated the gene expression of chemokines, interferon (IFN)-γ, IgA and PIgR in the ileum. Increased IFN-γ mRNA level was accompanied by higher proportion of natural killer cells and up-regulated IgA and PIgR gene expressions were in accordance with significantly higher percentage of CD19+ lymphocytes in the MLN. These findings indicate that probiotic L. reuteri has an antiviral effect on PCV2 in the intestine which is mediated by stimulation of local gut immune response.


2000 ◽  
Vol 13 (2) ◽  
pp. 143-153 ◽  
Author(s):  
ROMAN M. POGRANICHNYY ◽  
KYOUNG-JIN YOON ◽  
PERRY A. HARMS ◽  
SABRINA L. SWENSON ◽  
JEFFREY J. ZIMMERMAN ◽  
...  

2013 ◽  
Vol 110 (6) ◽  
pp. 1053-1060 ◽  
Author(s):  
Wenkai Ren ◽  
Yinghui Li ◽  
Xinglong Yu ◽  
Wei Luo ◽  
Gang Liu ◽  
...  

The present study was conducted to evaluate the immune-enhancing effects of dietaryl-glutamine supplementation in porcine circovirus type 2 (PCV2)-infected mice, and to examine the clearance effects of glutamine against PCV2 in experimentally infected mice. A total of sixty Kunming female mice were infected with PCV2 at a dose of 100 TCID50(50 % tissue culture infection dose) by intraperitoneal injection after 2 weeks of dietaryl-glutamine supplementation orl-alanine supplementation (as the control (isonitrogenous) group). The measured variables on 3rd, 5th, 7th, 9th and 11th d post-infection (dpi) included: (1) PCV2 virus loaded in the liver, spleen, heart, lung, kidney, ovary and serum was determined by real-time PCR; (2) IL-2, IL-6, IL-10, interferon (IFN)-α, IFN-γ and C-reactive protein levels in serum were measured by ELISA; (3) serum total superoxide dismutase activity was measured spectrophotometrically at 550 nm absorbance. Dietaryl-glutamine supplementation significantly increased serum IL-2 levels on the 3rd (P< 0·01), 5th (P< 0·01), 7th (P< 0·05) and 9th dpi, significantly (P< 0·05) increased serum IL-6 levels on 3rd dpi, significantly (P< 0·05) increased serum IFN-γ levels on the 9th and 11th dpi and significantly decreased (P< 0·01) serum IL-10 levels on the 9th and 11th dpi, compared with those in the control group. Meanwhile, the PCV2 virus genome was detected sporadically throughout the experimental period in both groups. Taken together, the present results suggest that dietaryl-glutamine supplementation enhances immune function in PCV2-infected mice.


2017 ◽  
Vol 65 (1) ◽  
pp. 135-146 ◽  
Author(s):  
Yu Mao ◽  
Jin Jun Li ◽  
Yuan Liu ◽  
Wei Dong ◽  
Pei Pang ◽  
...  

Porcine circovirus type 2- (PCV2-) associated reproductive disorders and enteritis have commonly been observed on PCV2-contaminated pig farms in recent years. In order to investigate disorders of intestinal immunity in piglets infected by PCV2 during the fetal period, 9 PCV2b-infected piglets and 6 non-infected piglets at one day of age were selected and euthanised prior to suckling. Samples of mesenteric lymph nodes (MLNs) and duodena were collected to investigate factors related to intestinal immunity and to detect lymphocytic apoptosis. The results indicated that there were no significant changes in the levels of IL-2, IL-10 and transforming growth factor-β (TGF-β) in the PCV2b-infected piglets but IFN-γ levels were significantly lower (P < 0.01) and IL-4 levels were significantly higher (P < 0.05) in infected piglets than in the controls. Furthermore, lymphocytic apoptosis increased in PCV2b-infected piglets and CD4+ to CD8+ ratios were lower in these piglets than in the controls. These findings suggest vertical transmission of PCV2b to fetuses, leading to an imbalance of intestinal immune function in piglets.


2003 ◽  
Vol 77 (20) ◽  
pp. 11232-11243 ◽  
Author(s):  
M. Fenaux ◽  
T. Opriessnig ◽  
P. G. Halbur ◽  
X. J. Meng

ABSTRACT Porcine circovirus type 2 (PCV2) is the primary causative agent of postweaning multisystemic wasting syndrome (PMWS), whereas the ubiquitous porcine circovirus type 1 (PCV1) is nonpathogenic for pigs. We report here the construction and characterization of two chimeric infectious DNA clones of PCV1 and PCV2. The chimeric PCV1-2 clone contains the PCV2 capsid gene cloned in the backbone of the nonpathogenic PCV1 genome. A reciprocal chimeric PCV2-1 DNA clone was also constructed by replacing the PCV2 capsid gene with that of PCV1 in the backbone of the PCV2 genome. The PCV1, PCV2, and chimeric PCV1-2 and PCV2-1 DNA clones were all shown to be infectious in PK-15 cells, and their growth characteristics in vitro were determined and compared. To evaluate the immunogenicity and pathogenicity of the chimeric infectious DNA clones, 40 specific-pathogen-free (SPF) pigs were randomly assigned into five groups of eight pigs each. Group 1 pigs received phosphate-buffered saline as the negative control. Group 2 pigs were each injected in the superficial inguinal lymph nodes with 200 μg of the PCV1 infectious DNA clone. Group 3 pigs were each similarly injected with 200 μg of the PCV2 infectious DNA clone, group 4 pigs were each injected with 200 μg of the chimeric PCV1-2 infectious DNA clone, and group 5 pigs were each injected with 200 μg of the reciprocal chimeric PCV2-1 infectious DNA clone. As expected, seroconversion to antibodies to the PCV2 capsid antigen was detected in group 3 and group 4 pigs. Group 2 and 5 pigs all seroconverted to PCV1 antibody. Gross and microscopic lesions in various tissues of animals inoculated with the PCV2 infectious DNA clone were significantly more severe than those found in pigs inoculated with PCV1, chimeric PCV1-2, and reciprocal chimeric PCV2-1 infectious DNA clones. These data indicated that the chimeric PCV1-2 virus with the immunogenic ORF2 capsid gene of pathogenic PCV2 cloned into the nonpathogenic PCV1 genomic backbone induces a specific antibody response to the pathogenic PCV2 capsid antigen but is attenuated in pigs. Future studies are warranted to evaluate the usefulness of the chimeric PCV1-2 infectious DNA clone as a genetically engineered live-attenuated vaccine against PCV2 infection and PMWS.


2011 ◽  
Vol 18 (11) ◽  
pp. 1865-1871 ◽  
Author(s):  
K. C. O'Neill ◽  
H. G. Shen ◽  
K. Lin ◽  
M. Hemann ◽  
N. M. Beach ◽  
...  

ABSTRACTPorcine circovirus type 2 (PCV2) vaccines have become widely used since they became available in 2006. It is not uncommon for producers to use PCV2 vaccines in pigs younger than what is approved by manufacturers. The objective of this study was to determine the efficacy of a chimeric and a subunit PCV2 vaccine administered at 5 or 21 days of age. Forty-eight PCV2-naïve piglets were randomly divided into six groups of eight pigs each. Vaccination was done at day 5 or day 21, followed by triple challenge with PCV2, porcine parvovirus (PPV), and porcine reproductive and respiratory syndrome virus (PRRSV) at day 49. Vaccinated pigs seroconverted to PCV2 approximately 14 days postvaccination and had a detectable neutralizing antibody response by 21 days postvaccination regardless of age at vaccination. At day 49, the pigs vaccinated with the chimeric vaccine had significantly higher levels of neutralizing antibodies than the pigs vaccinated with the subunit vaccine. After challenge, vaccinated pigs had significantly decreased levels of PCV2 viremia and a decreased prevalence and severity of microscopic lesions compared to the positive-control group, which had severe lymphoid lesions associated with abundant PCV2 antigen, compatible with PCV-associated disease. The results of this study indicate that, under the conditions of this study, vaccination of PCV2-naïve pigs at day 5 or day 21 resulted in development of a detectable humoral immune response and provided reduction or complete protection against PCV2 viremia and PCV2-associated lesions after triple challenge with PCV2, PPV, and PRRSV.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Ruihan Shi ◽  
Lei Hou ◽  
Jue Liu

AbstractPorcine circovirus type 2 (PCV2), which serves as a major causative agent of PCV2-associated diseases and causes severe loss to the pig industry worldwide, can dysregulate the immune response and induce immunosuppression in PCV2-infected pigs. Similar to PCV2, porcine circovirus type 3 (PCV3), a newly identified swine circovirus which might be closely associated with porcine dermatitis and nephropathy syndrome, reproductive disorder, and multisystemic inflammatory responses, also interferes with host immune defense. Interaction between host immune system and PCVs is considered to be a crucial determinant of pathogenicity in pigs. Here, we sought to briefly discuss the current knowledge regarding the interaction of porcine circovirus type 2 and/or 3 with host immune cells and immune responses to better depict the viral immunomodulatory capacity, pathogenic mechanisms, and the future research direction in host immune responses to infection with PCV2 and PCV3.


Sign in / Sign up

Export Citation Format

Share Document