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Frontiers in Immunology 2023In the present scenario, immunization is of utmost importance as it keeps us safe and protects us from infectious agents. Despite the great success in the field of... (Review)
Review
In the present scenario, immunization is of utmost importance as it keeps us safe and protects us from infectious agents. Despite the great success in the field of vaccinology, there is a need to not only develop safe and ideal vaccines to fight deadly infections but also improve the quality of existing vaccines in terms of partial or inconsistent protection. Generally, subunit vaccines are known to be safe in nature, but they are mostly found to be incapable of generating the optimum immune response. Hence, there is a great possibility of improving the potential of a vaccine in formulation with novel adjuvants, which can effectively impart superior immunity. The vaccine(s) in formulation with novel adjuvants may also be helpful in fighting pathogens of high antigenic diversity. However, due to the limitations of safety and toxicity, very few human-compatible adjuvants have been approved. In this review, we mainly focus on the need for new and improved vaccines; the definition of and the need for adjuvants; the characteristics and mechanisms of human-compatible adjuvants; the current status of vaccine adjuvants, mucosal vaccine adjuvants, and adjuvants in clinical development; and future directions.
Topics: Humans; Adjuvants, Vaccine; Vaccines; Immunization; Vaccination; Adjuvants, Immunologic
PubMed: 36911719
DOI: 10.3389/fimmu.2023.1043109 -
Current Opinion in Pediatrics Dec 2020Childhood obesity, with persistent chronic inflammation, is a worldwide epidemic. Obesity causes dysregulation throughout the immune system, affecting the balance and... (Review)
Review
PURPOSE OF REVIEW
Childhood obesity, with persistent chronic inflammation, is a worldwide epidemic. Obesity causes dysregulation throughout the immune system, affecting the balance and levels of cytokines, adipokines, and innate and adaptive immune cells. The present review focuses on the impact of obesity on immune function in children: altering the baseline activation state of immune cells and affecting the ability of the host to combat pathogens and malignancy and respond appropriately to vaccination.
RECENT FINDINGS
Obesity causes dysregulation of the immune system. Single-cell RNA-sequencing of adipose tissue and resident immune cells is quantifying the impact of obesity on the frequency of immune cell subsets and their states. The system-wide alterations in immune function in obesity are most evident upon perturbation, including the response to infection (e.g. increased risk of severe COVID-19 in the ongoing pandemic), vaccination, and malignancy. However, mechanistic research in pediatric obesity is limited and this impacts our ability to care for these children.
SUMMARY
We must better understand baseline and perturbed immune health in obese children to determine how to account for altered frequency and function of humoral and cellular immune components in acute infection, during vaccine design and when considering therapeutic options for this complex, medically vulnerable group.
Topics: Adipokines; Adipose Tissue; Child; Cytokines; Humans; Immune System; Immunity, Cellular; Immunity, Humoral; Infections; Pediatric Obesity; Vaccination
PubMed: 33105275
DOI: 10.1097/MOP.0000000000000953 -
Sports Health 2018Immunizations are a cornerstone of preventive care and an important consideration for team physicians caring for athletes. (Review)
Review
CONTEXT
Immunizations are a cornerstone of preventive care and an important consideration for team physicians caring for athletes.
EVIDENCE ACQUISITION
A PubMed search was performed from August 2016 through May 2017 as well as a website review of the Centers for Disease Control and Prevention, World Health Organization, and Immunization Action Coalition.
STUDY DESIGN
Clinical review.
LEVEL OF EVIDENCE
Level 4.
RESULTS
By keeping abreast of diseases endemic to nations to which athletes may be traveling as well as the vaccination status of the athletes, team physicians can provide appropriate advice regarding immunization and prevention of disease.
CONCLUSION
There are a host of regularly updated reliable websites to assist the team physician in these recommendations.
Topics: Athletes; Endemic Diseases; Humans; Immunization Schedule; Infection Control; Travel; Travel-Related Illness; Vaccination
PubMed: 30059267
DOI: 10.1177/1941738118788279 -
PLoS Pathogens May 2023Understanding immune mechanisms that mediate malaria protection is critical for improving vaccine development. Vaccination with radiation-attenuated Plasmodium...
Understanding immune mechanisms that mediate malaria protection is critical for improving vaccine development. Vaccination with radiation-attenuated Plasmodium falciparum sporozoites (PfRAS) induces high level of sterilizing immunity against malaria and serves as a valuable tool for the study of protective mechanisms. To identify vaccine-induced and protection-associated responses during malarial infection, we performed transcriptome profiling of whole blood and in-depth cellular profiling of PBMCs from volunteers who received either PfRAS or noninfectious mosquito bites, followed by controlled human malaria infection (CHMI) challenge. In-depth single-cell profiling of cell subsets that respond to CHMI in mock-vaccinated individuals showed a predominantly inflammatory transcriptome response. Whole blood transcriptome analysis revealed that gene sets associated with type I and II interferon and NK cell responses were increased in prior to CHMI while T and B cell signatures were decreased as early as one day following CHMI in protected vaccinees. In contrast, non-protected vaccinees and mock-vaccinated individuals exhibited shared transcriptome changes after CHMI characterized by decreased innate cell signatures and inflammatory responses. Additionally, immunophenotyping data showed different induction profiles of vδ2+ γδ T cells, CD56+ CD8+ T effector memory (Tem) cells, and non-classical monocytes between protected vaccinees and individuals developing blood-stage parasitemia, following treatment and resolution of infection. Our data provide key insights in understanding immune mechanistic pathways of PfRAS-induced protection and infective CHMI. We demonstrate that vaccine-induced immune response is heterogenous between protected and non-protected vaccinees and that inducted-malaria protection by PfRAS is associated with early and rapid changes in interferon, NK cell and adaptive immune responses. Trial Registration: ClinicalTrials.gov NCT01994525.
Topics: Humans; Animals; Malaria, Falciparum; Malaria; Plasmodium falciparum; Malaria Vaccines; Vaccination; Interferons; Immunity; Sporozoites
PubMed: 37195999
DOI: 10.1371/journal.ppat.1011051 -
Clinical Microbiology Reviews Jun 2023Clostridioides difficile infection (CDI) represents a significant challenge to public health. C. difficile-associated mortality and morbidity have led the U.S. CDC to... (Review)
Review
Clostridioides difficile infection (CDI) represents a significant challenge to public health. C. difficile-associated mortality and morbidity have led the U.S. CDC to designate it as an urgent threat. Moreover, recurrence or relapses can occur in up to a third of CDI patients, due in part to antibiotics being the primary treatment for CDI and the major cause of the disease. In this review, we summarize the current knowledge of innate immune responses, adaptive immune responses, and the link between innate and adaptive immune responses of the host against CDI. The other major determinants of CDI, such as C. difficile toxins, the host microbiota, and related treatments, are also described. Finally, we discuss the known therapeutic approaches and the current status of immunization strategies for CDI, which might help to bridge the knowledge gap in the generation of therapy against CDI.
Topics: Humans; Clostridioides difficile; Immunity, Innate; Vaccination; Clostridium Infections
PubMed: 37162338
DOI: 10.1128/cmr.00157-22 -
Communicable Diseases Intelligence... Mar 2021Australian Immunisation Register data have been analysed for children aged < 5 years, focusing on changes in vaccination coverage at standard age milestones (12, 24 and... (Review)
Review
Australian Immunisation Register data have been analysed for children aged < 5 years, focusing on changes in vaccination coverage at standard age milestones (12, 24 and 60 months) between 2018 and 2019. 'Fully vaccinated' coverage in 2019 increased by 0.1-0.4% at the three age milestones to 94.3% at 12 months, 90.2% at 24 months (in the context of additional antigens required at 24 months) and 94.2% at 60 months. Rotavirus vaccine coverage (2 doses) increased from 90.9% in 2018 to 91.9% in 2019. 'Fully vaccinated' coverage in Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Indigenous) children increased by 0.5-1.1% in 2019, reaching 92.9% at 12 months, 88.9% at 24 months and 96.9% at the 60 months (2.7 percentage points higher than in children overall). Recorded influenza vaccination coverage in children aged 6 months to < 5 years increased by 11.4 percentage points to 42.7% in Indigenous children in 2019, and by 15.6 percentage points to 41.8% in children overall. Longstanding issues with timeliness of vaccination in Indigenous children persisted, although the disparity between Indigenous and non-Indigenous children in on-time coverage (within 30 days of due date), for vaccines due at 4 months of age, decreased from 10.4-10.7 to 9.6-9.8 percentage points between 2018 and 2019. The timeliness of 'fully vaccinated' coverage was also examined at earlier age milestones (3 months after due date of last scheduled vaccine) of 9, 15, 21 and 51 months, by Indigenous status, socioeconomic status and remoteness of area of residence. Coverage in children living in the least-advantaged residential area quintile was 2.6-2.7% lower than that for those living in the most-advantaged quintile at the 9-, 15- and 21-month milestones, although these disparities were 0.5-1.5 percentage points lower than in 2018. Coverage at the earlier milestones in Indigenous children in remote areas was 1.5-6.7% percentage points lower than that for Indigenous children in major cities and regional areas, although there were some improvements since 2018. Importantly, although Indigenous children had lower coverage for the second dose of measles-mumps-rubella vaccine at 24 months (92.7% versus 93.3% overall), coverage increased to 98.8% at 60 months; coverage was also high overall at 96.4%, above the 95% target critical to measles control. In conclusion, this report demonstrates continuing improvements across a range of immunisation indicators in Australia in 2019. However, some issues with timeliness persist, particularly in Indigenous and socioeconomically disadvantaged children. New coverage targets for earlier protection in the first 2 years of life may be indicated, along with a review of current 'fully vaccinated' assessment algorithms, particularly at the 60-month age milestone.
Topics: Australia; Child; Child, Preschool; Humans; Immunization Programs; Infant; Measles-Mumps-Rubella Vaccine; Vaccination; Vaccination Coverage
PubMed: 33823758
DOI: 10.33321/cdi.2020.45.18 -
Vaccine Jun 2020Atherosclerosis, the major underlying cause of cardiovascular diseases (CVD), is the number one killer globally. The disease pathogenesis involves a complex interplay... (Review)
Review
Atherosclerosis, the major underlying cause of cardiovascular diseases (CVD), is the number one killer globally. The disease pathogenesis involves a complex interplay between metabolic and immune components. Although lipid-lowering drugs such as statins curb the risks associated with CVD, significant residual inflammatory risk remains. Substantial evidence from experimental models and clinical studies has established the role of inflammation and immune effector mechanisms in the pathogenesis of atherosclerosis. Several stages of the disease are affected by host-mediated antigen-specific adaptive immune responses that play either protective or proatherogenic roles. Therefore, strategies to boost an anti-atherogenic humoral and T regulatory cell response are emerging as preventative or therapeutic strategies to lowering inflammatory residual risks. Vaccination holds promise as an efficient, durable and relatively inexpensive approach to induce protective adaptive immunity in atherosclerotic patients. In this review, we discuss the status and opportunities for a human atherosclerosis vaccine. We describe (1) some of the immunomodulatory therapeutic interventions tested in atherosclerosis (2) the immune targets identified in pre-clinical and clinical investigations (3) immunization strategies evaluated in animal models (4) past and ongoing clinical trials to examine the safety and efficacy of human atherosclerosis vaccines and (5) strategies to improve and optimize vaccination in humans (antigen selection, formulation, dose and delivery).
Topics: Adaptive Immunity; Animals; Atherosclerosis; Humans; Inflammation; Mice; Vaccination; Vaccines
PubMed: 31964554
DOI: 10.1016/j.vaccine.2019.12.039 -
MBio Jun 2022Understanding immune memory to COVID-19 vaccines is critical for the design and optimal vaccination schedule for curbing the COVID-19 pandemic. Here, we assessed the...
Understanding immune memory to COVID-19 vaccines is critical for the design and optimal vaccination schedule for curbing the COVID-19 pandemic. Here, we assessed the status of humoral and cellular immune responses at 1, 3, 6, and 12 months after two-dose CoronaVac vaccination. A total of 150 participants were enrolled, and 136 of them completed the study through the 12-month endpoint. Our results show that, at 1 month after vaccination, both binding and neutralizing antibodies could be detected; the seropositive rate of binding antibodies and seroconversion rate of neutralizing antibodies were 99% and 50%, respectively. From 3 to 12 months, the binding and neutralizing antibodies declined over time. At 12 months, the binding and neutralizing antibodies were still detectable and significantly higher than the baseline. Gamma interferon (IFN-γ) and interleukin 2 (IL-2) secretion specifically induced by the receptor-binding domain (RBD) persisted at high levels until 6 months and could be observed at 12 months, while the levels of IL-5 and granzyme B (GzmB) were hardly detected, demonstrating a Th1-biased response. In addition, specific CD4 T central memory (T), CD4 effector memory (T), CD8 T, and CD8 terminal effector (T) cells were all detectable and functional up to 12 months after the second dose, as the cells produced IFN-γ, IL-2, and GzmB in response to stimulation of SARS-CoV-2 RBD. Our work provides evidence that CoronaVac induced not only detectable binding and neutralizing antibody responses, but also functional SARS-CoV-2-specific CD4 and CD8 memory T cells for up to 12 months. CoronaVac is an inactivated vaccine containing whole-virion SARS-CoV-2, which has been approved in 43 countries for emergency use as of 26 November 2021. However, the long-term immune persistence of the CoronaVac vaccine is still unknown. Here, we reported the status of the persistence of antibodies and cellular responses within 12 months after two doses of CoronaVac. Such data are crucial to inform ongoing and future vaccination strategies to combat COVID-19.
Topics: Antibodies, Neutralizing; Antibodies, Viral; CD8-Positive T-Lymphocytes; COVID-19; COVID-19 Vaccines; Humans; Immunity, Cellular; Immunity, Humoral; Interleukin-2; Pandemics; SARS-CoV-2; Vaccination; Vaccines, Inactivated
PubMed: 35475648
DOI: 10.1128/mbio.00181-22 -
Human Vaccines & Immunotherapeutics Jul 2020In the last two decades, the childhood vaccination coverage in most low and middle-income countries including India has increased. Additional vaccines are being offered... (Review)
Review
In the last two decades, the childhood vaccination coverage in most low and middle-income countries including India has increased. Additional vaccines are being offered through national immunization programs as well as through private sector and the benefits of vaccination are reaching to more children than ever. This has resulted in major decrease in vaccine preventable diseases and contributed to decline in the morbidity and mortality rates. This development is expected to result in epidemiological transition (which is already happening) and mandates for policies and strategies to extend the benefit of available vaccines and vaccination beyond traditionally target age groups to include the adults, elderly and the at-risk populations. This article reviews the present status of adult vaccination in India and proposes a few approaches to move towards life course vaccination.
Topics: Adult; Aged; Child; Humans; Immunization Programs; India; Vaccination; Vaccination Coverage; Vaccines
PubMed: 31743073
DOI: 10.1080/21645515.2019.1692564 -
BMC Infectious Diseases Jan 2022Diphtheria is a contagious vaccine-preventable disease that contributes to the high morbidity and mortality among under 5 children, especially in Yemen. As a consequence...
BACKGROUND
Diphtheria is a contagious vaccine-preventable disease that contributes to the high morbidity and mortality among under 5 children, especially in Yemen. As a consequence of war and collapse of the health system, a fatal epidemic occurred at the end of 2017. This study aims to describe the epidemiology of diphtheria by time, place, and person and vaccination status of affected children.
METHODS
A study was conducted in Sada'a governorate by using accumulative line list of diphtheria from November 2017 to September 2020 at electronic Integrated Disease Early Warning System (eIDEWS). The case definition of WHO was adopted. Data was analyzed by Microsoft Excel and Epi info- version 7.2 and multivariable logistic analysis used for identifying significant associated factors.
RESULTS
747 cases were met of WHO case definition. The annual peak of cases started during week 31 and weak 49. Males were slightly more than females (51% vs 49%) and about 35% of cases involved children aged 10 to < 15 years. The overall incidence of diphtheria and case fatality rate (CFR) were 69/ 100,000 and 6.4%, respectively. The highest CFR was among age groups under 5 years 11% (P < 0.001) and among females was 8%. Dysphagia and swollen lymph nodes were the predominant symptoms 98%, 92%, respectively. Based on the Vaccination status, the percentage of unvaccinated and unknown were 53% and 41% respectively, with CFR 11% among cases who received one dose. Furthermore, the most case were from Sahar 40% with case fatality rate 8% and the highest CFR was significantly higher among cases in border and ongoing conflict district (P < 0.05).
CONCLUSIONS
The findings highlight that diphtheria is still an ongoing cause of morbidity and mortality among under 5 children in Sada'a that is rising with the low diphtheria immunization coverage. Therefore, concomitant efforts should now focus on improving and monitoring routine immunization across all age groups and healthcare services, especially in borders and continuing conflict districts.
Topics: Child; Child, Preschool; Diphtheria; Disease Outbreaks; Female; Humans; Infant; Male; Vaccination; Vaccination Coverage; Yemen
PubMed: 35016630
DOI: 10.1186/s12879-022-07033-x