scholarly journals Long-term live imaging reveals cytosolic immune responses of host hepatocytes against Plasmodium infection and parasite escape mechanisms

Autophagy ◽  
2015 ◽  
Vol 11 (9) ◽  
pp. 1561-1579 ◽  
Author(s):  
Monica Prado ◽  
Nina Eickel ◽  
Mariana De Niz ◽  
Anna Heitmann ◽  
Carolina Agop-Nersesian ◽  
...  
Keyword(s):  
Immune Responses ◽  
Live Imaging ◽  
Plasmodium Infection

scholarly journals Inflammatory Neuropsychiatric Disorders and COVID-19 Neuroinflammation

2021 ◽  
pp. 1-55
Author(s):  
Siu Wa Tang ◽  
Daiga Helmeste ◽  
Brian Leonard
Keyword(s):  
Immune Responses ◽  
Clinical Management ◽  
Neuronal Damage ◽  
Treatment Resistance ◽  
Neuropsychiatric Disorders ◽  
Acute Stage ◽  
Management Approach ◽  
Neuropsychiatric Diseases ◽  
Anti Inflammatory

Abstract Neuropsychiatric sequalae to COVID-19 infection are beginning to emerge, like previous Spanish influenza and SARS episodes. Streptococcal infection in pediatric patients causing OCD (PANDAS) is another recent example of an infection-based psychiatric disorder. Inflammation associated with neuropsychiatric disorders has been previously reported but there is no standard clinical management approach established. Part of the reason is that it is unclear what factors determine the specific neuronal vulnerability and the efficacy of anti-inflammatory treatment in neuroinflammation. The emerging COVID-19 data suggested that in the acute stage, wide-spread neuronal damage appears to be the result of abnormal and overactive immune responses and cytokine storm is associated with poor prognosis. It is still too early to know if there are long term specific neuronal or brain regional damages associated with COVID-19, resulting in distinct neuropsychiatric disorders. In several major psychiatric disorders where neuroinflammation is present, patients with abnormal inflammatory markers may also experience less than favorable response or treatment resistance when standard treatment is used alone. Evidence regarding the benefits of co-administered anti-inflammatory agents such as COX-2 inhibitor is encouraging in selected patients though may not benefit others. Disease modifying therapies are increasingly being applied to neuropsychiatric diseases characterized by abnormal or hyperreactive immune responses. Adjunct anti-inflammatory treatment may benefit selected patients and is definitely an important component of clinical management in the presence of neuroinflammation.

scholarly journals Cardiac Cell Therapy: Insights into the Mechanisms of Tissue Repair

2021 ◽  
Vol 22 (3) ◽  
pp. 1201
Author(s):  
Hsuan Peng ◽  
Kazuhiro Shindo ◽  
Renée R. Donahue ◽  
Ahmed Abdel-Latif
Keyword(s):  
Stem Cell ◽  
Immune Responses ◽  
Tissue Repair ◽  
Molecular Mechanisms ◽  
Clinical Evidence ◽  
Current Knowledge ◽  
Cell Delivery ◽  
Cardiac Cell Therapy ◽  
Stem Cell Treatment

Stem cell-based cardiac therapies have been extensively studied in recent years. However, the efficacy of cell delivery, engraftment, and differentiation post-transplant remain continuous challenges and represent opportunities to further refine our current strategies. Despite limited long-term cardiac retention, stem cell treatment leads to sustained cardiac benefit following myocardial infarction (MI). This review summarizes the current knowledge on stem cell based cardiac immunomodulation by highlighting the cellular and molecular mechanisms of different immune responses to mesenchymal stem cells (MSCs) and their secretory factors. This review also addresses the clinical evidence in the field.

scholarly journals COVID-19: Mechanisms of Vaccination and Immunity

Vaccines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 404 ◽  
Author(s):  
Daniel E. Speiser ◽  
Martin F. Bachmann
Keyword(s):  
Immune Responses ◽  
Clinical Management ◽  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Public Life ◽  
High Affinity ◽  
Vaccination Strategies ◽  
Detailed Evaluation ◽  
Pros And Cons

Vaccines are needed to protect from SARS-CoV-2, the virus causing COVID-19. Vaccines that induce large quantities of high affinity virus-neutralizing antibodies may optimally prevent infection and avoid unfavorable effects. Vaccination trials require precise clinical management, complemented with detailed evaluation of safety and immune responses. Here, we review the pros and cons of available vaccine platforms and options to accelerate vaccine development towards the safe immunization of the world’s population against SARS-CoV-2. Favorable vaccines, used in well-designed vaccination strategies, may be critical for limiting harm and promoting trust and a long-term return to normal public life and economy.

scholarly journals Posttranslational Regulation of IL-23 Production Distinguishes the Innate Immune Responses to Live Toxigenic versus Heat-Inactivated Vibrio cholerae

mSphere ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Ana A. Weil ◽  
Crystal N. Ellis ◽  
Meti D. Debela ◽  
Taufiqur R. Bhuiyan ◽  
Rasheduzzaman Rashu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Cholera Toxin ◽  
Vibrio Cholerae ◽  
Protective Immunity ◽  
Innate Immune ◽  
Posttranslational Regulation ◽  
Content Type ◽  
In Cells ◽  
Cholera Vaccines

ABSTRACT Vibrio cholerae infection provides long-lasting protective immunity, while oral, inactivated cholera vaccines (OCV) result in more-limited protection. To identify characteristics of the innate immune response that may distinguish natural V. cholerae infection from OCV, we stimulated differentiated, macrophage-like THP-1 cells with live versus heat-inactivated V. cholerae with and without endogenous or exogenous cholera holotoxin (CT). Interleukin 23A gene (IL23A) expression was higher in cells exposed to live V. cholerae than in cells exposed to inactivated organisms (mean change, 38-fold; 95% confidence interval [95% CI], 4.0 to 42; P < 0.01). IL-23 secretion was also higher in cells exposed to live V. cholerae than in cells exposed to inactivated V. cholerae (mean change, 5.6-fold; 95% CI, 4.4 to 11; P < 0.001). This increase in IL-23 secretion was more marked than for other key innate immune cytokines (e.g., IL-1β and IL-6) and dependent on exposure to the combination of both live V. cholerae and CT. While IL-23 secretion was reduced following stimulation with either heat-inactivated wild-type V. cholerae or a live isogenic ctxAB mutant of V. cholerae, the addition of exogenous CT restored IL-23 secretion in combination with the live isogenic ctxAB mutant V. cholerae, but not when it was paired with stimulation by heat-inactivated V. cholerae. The posttranslational regulation of IL-23 under these conditions was dependent on the activity of the cysteine protease cathepsin B. In humans, IL-23 promotes the differentiation of Th17 cells to T follicular helper cells, which maintain and support long-term memory B cell generation after infection. Based on these findings, the stimulation of IL-23 production may be a determinant of protective immunity following V. cholerae infection. IMPORTANCE An episode of cholera provides better protection against reinfection than oral cholera vaccines, and the reasons for this are still under study. To better understand this, we compared the immune responses of human cells exposed to live Vibrio cholerae with those of cells exposed to heat-killed V. cholerae (similar to the contents of oral cholera vaccines). We also compared the effects of active cholera toxin and the inactive cholera toxin B subunit (which is included in some cholera vaccines). One key immune signaling molecule, IL-23, was uniquely produced in response to the combination of live bacteria and active cholera holotoxin. Stimulation with V. cholerae that did not produce the active toxin or was killed did not produce an IL-23 response. The stimulation of IL-23 production by cholera toxin-producing V. cholerae may be important in conferring long-term immunity after cholera.

scholarly journals Seroconversion rates following 2 doses of measles- mumps- rubella vaccination given at the ages 12 and 18 months: data for possible additional dose at older age

2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Hana Saffar ◽  
Sayed Jaber Mousavi ◽  
Hiva Saffar ◽  
Mohammad-Reza Parsaei ◽  
Gholam-Reza Ghorbani ◽  
...  
Keyword(s):  
Immune Responses ◽  
Age Groups ◽  
High Rate ◽  
Healthy Children ◽  
Mmr Vaccine ◽  
Vaccine Failure ◽  
Iranian Children ◽  
Rubella Vaccination ◽  
Infant Pair

Abstract Background Despite high rate of vaccination coverage with 2-doses of measles containing vaccine among Iranian children, outbreaks of measles occurred among different age groups and fully vaccinated subjects. Although the main reason for these outbreaks is unknown, however, vaccine failure was supposed to be an important cause. This study was designed to determine the seroconversion rates to measles- mumps- rubella (MMR) vaccine currently in use among Iranian children. Methods This prospective study was conducted among healthy children older than 12 months who were candidates of scheduled MMR vaccination. Blood samples were obtained from each mother- infant pair just before vaccination, and from infants 4–6 weeks after MMR1 and MMR2 immunization. Collected sera were tested for specific lgG antibodies against MMR agents using ELISA method. The proportion of seroprotected subjects among mother- infant pairs before vaccination as well as the prevalence rates of seroconversion after MMR1 and MMR2 vaccination were calculated. Collected data were analyzed using descriptive statistical methods. Results During 22-months study period, 92 mother- infant pairs were participated. Seroimmunity rates against MMR viruses were 85.8%, 84.7% and 86.9% for mothers, and 3.2%, 2.1% and 1.0% for children, respectively. After MMR1 vaccination from 52 seronegative children, 80.7%, 78.8% and 75% were seroconverted. These rates increased to 94.8%, 89.7% and 94.8% after the MMR2 vaccination. Also, the specific immunity was enhanced among seropositive children. Conclusion Majority of the mothers and few infants were immune to MMR viruses prior to MMR1 vaccination. Immune responses detected after MMR1 injection, and overall seroconversion rates achieved after 2-doses of MMR vaccination were less than expected and inadequate to preserve long-term protection against MMR agents.

scholarly journals The Role of Interferons in Driving Susceptibility to Asthma Following Bronchiolitis: Controversies and Research Gaps

2021 ◽  
Vol 12 ◽  
Author(s):  
Heidi Makrinioti ◽  
Andrew Bush ◽  
James Gern ◽  
Sebastian Lennox Johnston ◽  
Nikolaos Papadopoulos ◽  
...  
Keyword(s):  
Immune Responses ◽  
Acute Infection ◽  
Respiratory Viruses ◽  
Future Research ◽  
Innate Immune Responses ◽  
Asthmatic Children ◽  
Recurrent Wheeze ◽  
The Relationship

Bronchiolitis is the most common cause of hospitalization in infancy and is associated with a higher risk for the development of childhood asthma. However, not all children hospitalized with bronchiolitis will develop asthma. The mechanisms underlying asthma development following bronchiolitis hospitalization are complex. Immune responses to respiratory viruses may underlie both bronchiolitis severity and long-term sequela (such as asthma). Interferons (IFNs) are important components of innate immune responses to respiratory viruses and could influence both asthma development and asthma exacerbations. However, the nature of the relationship between interferon production and wheezing illnesses is controversial. For example, low peripheral blood IFN responses at birth have been linked with recurrent wheeze and asthma development. In contrast, there is evidence that severe illnesses (e.g., hospitalization for bronchiolitis) are associated with increased IFN responses during acute infection (bronchiolitis hospitalization) and a higher risk for subsequent asthma diagnosis. Furthermore, mechanistic studies suggest that bronchial epithelial cells from asthmatic children have impaired IFN responses to respiratory viruses, which may enable increased viral replication followed by exaggerated secondary IFN responses. This review aims to discuss controversies around the role of IFNs as drivers of susceptibility to asthma development following bronchiolitis hospitalization. Past evidence from both mechanistic and cohort studies are discussed. We will highlight knowledge gaps that can inform future research study design.

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