Age and immunity: What is "immunosenescence"?

Cancer cell-intrinsic mechanisms driving acquired immune tolerance

Immune evasion is a hallmark of cancer, enabling tumors to survive contact with the host immune system and evade the cycle of immune recognition and destruction. Here, we review the current understanding of the cancer cell-intrinsic factors driving immune evasion. We focus on T cells as key effectors of anti-cancer immunity and argue that cancer cells evade immune destruction by gaining control over pathways that usually serve to maintain physiological tolerance to self. Using this framework, we place recent mechanistic advances in the understanding of cancer immune evasion into broad categories of control over T cell localization, antigen recognition, and acquisition of optimal effector function. We discuss the redundancy in the pathways involved and identify knowledge gaps that must be overcome to better target immune evasion, including the need for better, routinely available tools that incorporate the growing understanding of evasion mechanisms to stratify patients for therapy and trials.

Influence of age and fitness level on immune responses of T and NK cells in healthy physically active subjects after strenuous aerobic exercise: a cross-sectional study

Aim

The aim of this study is to analyze whether immune responses after strenuous exercise are influenced by chronological age and fitness level in physically active healthy men.

Methods

Cross-sectional study with a sample of 32 physically active men. Participants were divided into two groups based on chronological age (younger: age 21.8 ± 1.8 vs. older: age 34.6 ± 8.3) and subsequently regrouped and divided based on fitness level (More conditioned: excellent and superior VO2max vs. Less conditioned: VO2max: weak, regular and good). Fitness was classified according to VO2max levels obtained by a treadmill test using a gas analyzer. Before and immediately after the ergospirometry test, blood samples were collected for evaluation of immunological markers: leukocytes, neutrophils, lymphocytes and subpopulations.

Results

Chronological age had a moderate effect on CD3+CD4+ lymphocyte count (effect size: 0.204) and CD4/CD8 ratio (effect size: 0.278), favoring older subjects. The level of physical fitness had no significant effect on the analyzed immunological markers.

Conclusions

Immune responses observed immediately after strenuous exercise may be more dependent on chronological age than on fitness level in healthy, physically active men.

Immunosenescence and Immune Exhaustion Are Associated with Levels of Protein-Bound Uremic Toxins in Patients on Hemodialysis

BACKGROUND

The accumulation of protein-bound uremic toxins (PBUTs) in chronic kidney disease may affect patients' immune status. The aim of the study was to evaluate their potential impacts on lymphocyte alterations in patients on hemodialysis (HD).

METHODS

The plasma levels of PBUTs were assessed in 54 patients on HD and 31 healthy individuals, using ultra-performance liquid chromatography. The results correlated with the senescent and exhausted status of lymphocytes, based on certain surface molecules, analyzed by flow cytometry.

RESULTS

The plasma levels of PBUTs were significantly increased in the patients on HD compared with the healthy controls. The patients with residual kidney function had reduced hippuric acid (HA) levels, total (p = 0.03) and free (p = 0.04), and free IxS levels (p = 0.02). The total and free HA levels correlated negatively with less differentiated subpopulations, CD4+CD45RA+CD31+ (p = 0.037 and p = 0.027), CD8+CD28+CD57- (p = 0.01, p = 0.01), and naïve B cells (CD19+IgD+CD27-) (p = 0.04, p = 0.03). Both the total and the free pCS levels correlated positively with exhausted CD4 cells, p = 0.02 and p = 0.01, respectively. A multivariate analysis showed that IxS and age were the main independent parameters implicated in the reduction intotal CD4 and B lymphocytes and their naïve and early differentiated subsets.

CONCLUSIONS

Increased PBUTs levels are associated with immune disturbances of patients on HD, HA, and IxS in the immunosenescent and pCS in the immunoexhaustion alterations.

Temporal trends, sex differences, and age-related disease influence in Neutrophil, Lymphocyte count and Neutrophil to Lymphocyte-ratio: results from InCHIANTI follow-up study

BACKGROUND

Neutrophils and lymphocytes represent the larger percentage of all white blood cells, they vary with age, with a progressive increase of the ratio in the first years of life, and then tend to remain at similar levels in steady state condition during adult age. Neutrophils to lymphocytes-ratio (NL-ratio) was proposed as an effective and low-cost marker to monitor and predict the evolution of several clinical conditions. The main objective of the study is to analyze its temporal trend variation, over twenty years' follow-up, according to age, sex, and main clinical diagnosis, in a large representative Italian population.

METHODS

The InCHIANTI study enrolled representative samples from the registry list of two towns in Tuscany, Italy. Baseline data were collected in 1998, and last follow-up visits were made in 2015-18. 1343 out of the 1453 participants enrolled were included, and consented to donate a blood sample. All subjects were assessed and followed for life-style, clinical condition, physical performance, and underwent an instrumental diagnostic session.

RESULTS

The NL-ratio showed a statistically significant interaction between birth-cohort and time of the study (p-value = 0.005). A gender dimorphism was recognized in the neutrophils absolute count and in the NL-ratio. Moreover, in female participants only, those who reported CHF had lower neutrophil-count and NL-ratio; whereas an increase in creatinine clearance was directly associated with NL-ratio. In male subjects, an increase of BMI was inversely associated with both NL-ratio and neutrophils-count during the follow-up; a similar association but in the opposite direction was observed in female participants.

CONCLUSION

NL-ratio is a more reliable predictor of healthy aging than absolute lymphocytes and/or neutrophils counts. It is associated with the changes induced by disease, lifestyle, and environmental challenges in the immune system. NL-ratio confirms the gender dimorphism in the occurrence of inflammation-driven diseases, thus providing additional evidence for the necessity of tailored sex-specific measures to prevent and treat such diseases.

Effect of Ramadan fasting on salivary IgA, serum IgA, IL-17, and IL-22 levels

Background: nutritional factors might affect the number and function of immune cells for instance the production of cytokines and immunoglobulins. Ramadan fasting is intermittent abstinence from eating and drinking for almost four weeks. Aim: The present study aimed to investigate the influence of intermittent fasting on serum IgA, salivary IgA (sIgA), interleukin (IL)-17, and IL-22 levels. Methods: 40 healthy men aged 19-29 years were evaluated before and during the fourth week of Ramadan fasting for IgA levels by the nephelometric method as well as salivary IgA (sIgA), IL-17, and IL-22 amounts using enzyme-linked immunosorbent assay (ELISA). Results: serum IgA levels reduced significantly at the end of Ramadan fasting (225.8 ± 87 vs. 196 ± 70 mg/dl) (p-value<0.001); however, sIgA amounts did not differ between before and the last week of Ramadan. Serum IL-17 reduced significantly (2.93 ± 1.51 vs. 2.17 ± 1.33 pg/ml) (p-value = 0.006) whereas IL-22 levels remained approximately unchanged. Summary: four weeks of intermittent fasting during Ramadan reduced the serum levels of IgA and IL-17 but did not affect the production of sIgA and IL-22. These findings indicate a limited impact of intermittent fasting on mucosal immunity.

Real-world effectiveness of COVID-19 vaccines: A retrospective cohort study of vaccinated individuals in Jazan, Saudi Arabia

BACKGROUND

COVID-19 (Coronavirus Disease 2019) vaccinations are a critical control measure for the coronavirus pandemic that began in 2019. Several COVID-19 vaccines have been developed, and their effectiveness will almost certainly vary.

OBJECTIVE

This study aimed to assess how effective two doses of the Pfizer and Oxford-AstraZeneca vaccines were in preventing SARS-CoV-2 infection six months after administration.

METHODS

This is a retrospective cohort study of adult individuals from the Jazan Region of Saudi Arabia who received their second dose of the COVID-19 vaccine [Pfizer and Oxford-AstraZeneca (ASZ)] between April and June 2021. The monitoring and follow-up period continued until the end of January 2022. Data were retrieved from the Health Electronic Surveillance Network and National Vaccination Records. Logistic regression was performed to assess the risk of COVID-19 infection among the vaccinated subjects.

RESULTS

This study included randomly enrolled 4458 participants in Jazan who received two doses of the COVID-19 vaccine during the research period. The majority of them received the Pfizer vaccine (3136/4458; 70.3%), while the remaining received the ASZ vaccine (1322/4458; 29.7%). The study participants' mean age was 59.7 years, with a male-to-female ratio of 1.9:1.0 (2920:1538). The results showed that the Pfizer and ASZ vaccines' protection against infection decreased from 93.2% and 90.2%, respectively, during the first three months, to 68.5% and 68.1% after a six-month interval. In the current study population, being Saudi Arabian, younger as well as having longer intervals between vaccines or crossing a 6-month period after the second vaccine dose were factors linked to higher rates of breakthrough infections.

CONCLUSION

Our findings revealed variations in the efficacy of different COVID-19 vaccine types against COVID-19 breakthrough infections. The Pfizer (mRNA-based) vaccine was found to be relatively more effective than the ASZ (DNA-based) vaccine.

Risk factors for death in hospitalized COVID-19 patients in Africa: A systematic review and meta-analysis

BACKGROUND

The coronavirus disease 2019 has quickly spread worldwide since it first appeared in Wuhan, China, in late 2019. The most affected country in Africa was South Africa. This study aimed to identify the risk factors for death in hospitalized COVID-19 patients in Africa.

METHODS

We conducted a systematic review following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. We searched articles from the following database: PubMed, Embase, Cochrane Library, Medline, and COVID-19 Research Database. We used Google Scholar for gray literature. The language used in this article was English. The last search was conducted on January 15, 2023. Pooled HRs, or ORs, and 95% confidence intervals, were calculated separately to identify the risk factors for death in hospitalized COVID-19 patients. Heterogeneity was assessed by Cochran's Q statistic and the I2 test. The Egger test was used to assess publication bias. Subgroup analysis was performed to determine the source of heterogeneity. Data analysis was performed using Stata version 17. A P value < .05 was considered significant.

RESULTS

A total of 16,600 articles were obtained from the database search; finally, 16 articles met the inclusion criteria and were eligible for data extraction. The analysis revealed that the pooled prevalence of mortality in hospitalized COVID-19 patients was 13.9%. Advanced age was a significant risk factor for death in hospitalized COVID-19 patients, with the pooled coronavirus mortality HR and OR being 3.73 (95% CI: 2.27-5.19) and 1.04 (95% CI: 1.02-1.06), respectively. In addition, male gender (pOR 1.23; 95% CI: 1.07-1.40), patients with diabetes mellitus (DM) (pOR 1.26; 95% CI: 1.01-1.51), hypertension (HTN) (pOR 1.56; 95% CI: 1.27-1.85), chronic kidney disease (CKD) (pHR 5.43; 95% CI: 0.18-10.67), severe or critical conditions (pOR 9.04; 95% CI: 3.14-14.94) had a significantly increased risk of coronavirus-related mortality. The main limitations of the present study stem from the predominant use of published studies, which could introduce publication bias.

CONCLUSION

According to this study, advanced age, male gender, hypertension, diabetes mellitus, chronic kidney disease, and severe or critical condition were clinical risk factors associated with death outcomes in hospitalized COVID-19 patients in Africa.

Temporal trends, sex differences, and age-related disease influence in Neutrophil, Lymphocyte count and Neutrophil to Lymphocyte-ratio. Results from InCHIANTI follow-up study

Background Neutrophils and lymphocytes represent the larger percentage of all white bloodcells, they vary with age, with a progressive increase of the ratio in the first years of life, and then tend to remain at similar levels in steady state condition during adult age. Neutrophils to lymphocytes-ratio (NL-ratio) was proposed as an effective and low-cost marker to monitor and predict the evolution of severalclinical conditions. The main objective of the study is to analyze its temporal trend variation, over twenty years' follow-up, according to age, sex, and main clinical diagnosis, in a large representative Italian population. Methods The InCHIANTI study enrolled representative samples from the registry list of two towns in Tuscany, Italy. Baseline data were collected in 1998, and last follow-up visits were made in 2015-18. 1343 out of the 1453 participants enrolled were included, and consented to donate a blood sample. All subjects were assessed and followed for life-style, clinical condition, physical performance, and underwent an instrumental diagnostic session. Results The NL-ratio showed a statistically significant interaction between birth-cohort and time of the study (p-value=0.005). A gender dimorphism was recognized in the neutrophils absolute count and in the NL-ratio. Moreover, in female participants only, those who reported CHF had lower neutrophil-count and NL-ratio; whereas an increase in creatinine clearance was directly associated with NL-ratio. In male subjects, an increase of BMI was inversely associated with both NL-ratio and neutrophils-count during the follow-up; a similar association but in the opposite direction was observed in female participants. Conclusion NL-ratio is a more reliable predictor of healthy aging than absolute lymphocytes and/or neutrophils counts. It is associated with the changes induced by disease, lifestyle, and environmental challenges in the immune system. NL-ratio confirms the gender dimorphism in the occurrence of inflammation-driven diseases, thus providing additional evidence for the necessity of tailored sex-specific measures to prevent and treat such diseases.

Obesity-induced thymic involution and cancer risk

Declining thymic functions associated either with old age (i.e., age-related thymic involution), or with acute involution as a result of stress, infectious disease, or cytoreductive therapies (e.g., chemotherapy/radiotherapy), have been associated with cancer development. A key mechanism underlying such increased cancer risk is the thymus-dependent debilitation of adaptive immunity, which is responsible for orchestrating immunoediting mechanisms and tumor immune surveillance. In the past few years, a blooming set of evidence has intriguingly linked obesity with cancer development and progression. The majority of such studies has focused on obesity-driven chronic inflammation, steroid/sex hormone and adipokine production, and hyperinsulinemia, as principal factors affecting the tumor microenvironment and driving the development of primary malignancy. However, experimental observations about the negative impact of obesity on T cell development and maturation have existed for more than half a century. Here, we critically discuss the molecular and cellular mechanisms of obesity-driven thymic involution as a previously underrepresented intermediary pathology leading to cancer development and progression. This knowledge could be especially relevant in the context of childhood obesity, because impaired thymic function in young individuals leads to immune system abnormalities, and predisposes to various pediatric cancers. A thorough understanding behind the molecular and cellular circuitries governing obesity-induced thymic involution could therefore help towards the rationalized development of targeted thymic regeneration strategies for obese individuals at high risk of cancer development.

Metabolism and senescence in the immune microenvironment of osteosarcoma: focus on new therapeutic strategies

Osteosarcoma is a highly aggressive and metastatic malignant tumor. It has the highest incidence of all malignant bone tumors and is one of the most common solid tumors in children and adolescents. Osteosarcoma tissues are often richly infiltrated with inflammatory cells, including tumor-associated macrophages, lymphocytes, and dendritic cells, forming a complex immune microenvironment. The expression of immune checkpoint molecules is also high in osteosarcoma tissues, which may be involved in the mechanism of anti-tumor immune escape. Metabolism and senescence are closely related to the immune microenvironment, and disturbances in metabolism and senescence may have important effects on the immune microenvironment, thereby affecting immune cell function and immune responses. Metabolic modulation and anti-senescence therapy are gaining the attention of researchers as emerging immunotherapeutic strategies for tumors. Through an in-depth study of the interconnection of metabolism and anti- senescence in the tumor immune microenvironment and its regulatory mechanism on immune cell function and immune response, more precise therapeutic strategies can be developed. Combined with the screening and application of biomarkers, personalized treatment can be achieved to improve therapeutic efficacy and provide a scientific basis for clinical decision-making. Metabolic modulation and anti- senescence therapy can also be combined with other immunotherapy approaches, such as immune checkpoint inhibitors and tumor vaccines, to form a multi-level and multi-dimensional immunotherapy strategy, thus further enhancing the effect of immunotherapy. Multidisciplinary cooperation and integrated treatment can optimize the treatment plan and maximize the survival rate and quality of life of patients. Future research and clinical practice will further advance this field, promising more effective treatment options for patients with osteosarcoma. In this review, we reviewed metabolic and senescence characteristics in the immune microenvironment of osteosarcoma and related immunotherapies, and provide a reference for development of more personalized and effective therapeutic strategies.

Anti-Inflammatory Effects of Nutritionally Relevant Concentrations of Oleuropein and Hydroxytyrosol on Peripheral Blood Mononuclear Cells: An Age-Related Analysis

Immunosenescence and inflammaging facilitate the insurgence of chronic diseases. The Mediterranean diet is a non-invasive intervention to improve the chronic low-grade inflammatory status associated with aging. Olive oil oleuropein (OLE) and hydroxytyrosol (HT) demonstrated a controversial modulatory action on inflammation in vitro when tested at concentrations exceeding those detectable in human plasma. We studied the potential anti-inflammatory effects of OLE and HT at nutritionally relevant concentrations on peripheral blood mononuclear cells (PBMCs) as regards cell viability, frequency of leukocyte subsets, and cytokine release, performing an age-focused analysis on two groups of subjects: Adult (age 18-64 years) and Senior (age ≥ 65 years). OLE and HT were used alone or as a pre-treatment before challenging PBMCs with lipopolysaccharide (LPS). Both polyphenols had no effect on cell viability irrespective of LPS, but 5 µM HT had an LPS-like effect on monocytes, reducing the intermediate subset in Adult subjects. OLE and HT had no effect on LPS-triggered release of TNF-α, IL-6 and IL-8, but 5 µM HT reduced IL-10 secretion by PBMCs from Adult vs. Senior group. In summary, nutritionally relevant concentrations of OLE and HT elicit no anti-inflammatory effect and influence the frequency of immune cell subsets with age-related different outcomes.

Inflammation and aging: signaling pathways and intervention therapies

Aging is characterized by systemic chronic inflammation, which is accompanied by cellular senescence, immunosenescence, organ dysfunction, and age-related diseases. Given the multidimensional complexity of aging, there is an urgent need for a systematic organization of inflammaging through dimensionality reduction. Factors secreted by senescent cells, known as the senescence-associated secretory phenotype (SASP), promote chronic inflammation and can induce senescence in normal cells. At the same time, chronic inflammation accelerates the senescence of immune cells, resulting in weakened immune function and an inability to clear senescent cells and inflammatory factors, which creates a vicious cycle of inflammation and senescence. Persistently elevated inflammation levels in organs such as the bone marrow, liver, and lungs cannot be eliminated in time, leading to organ damage and aging-related diseases. Therefore, inflammation has been recognized as an endogenous factor in aging, and the elimination of inflammation could be a potential strategy for anti-aging. Here we discuss inflammaging at the molecular, cellular, organ, and disease levels, and review current aging models, the implications of cutting-edge single cell technologies, as well as anti-aging strategies. Since preventing and alleviating aging-related diseases and improving the overall quality of life are the ultimate goals of aging research, our review highlights the critical features and potential mechanisms of inflammation and aging, along with the latest developments and future directions in aging research, providing a theoretical foundation for novel and practical anti-aging strategies.

Innate and adaptive immunity to SARS-CoV-2 and predisposing factors

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), has affected all countries worldwide. Although some symptoms are relatively mild, others are still associated with severe and even fatal clinical outcomes. Innate and adaptive immunity are important for the control of SARS-CoV-2 infections, whereas a comprehensive characterization of the innate and adaptive immune response to COVID-19 is still lacking and the mechanisms underlying immune pathogenesis and host predisposing factors are still a matter of scientific debate. Here, the specific functions and kinetics of innate and adaptive immunity involved in SARS-CoV-2 recognition and resultant pathogenesis are discussed, as well as their immune memory for vaccinations, viral-mediated immune evasion, and the current and future immunotherapeutic agents. We also highlight host factors that contribute to infection, which may deepen the understanding of viral pathogenesis and help identify targeted therapies that attenuate severe disease and infection.

Immunosenescence and Skin: A State of Art of Its Etiopathogenetic Role and Crucial Watershed for Systemic Implications

Immunosenescence is a complex multifactorial phenomenon consisting of wide-ranging remodeling of the immune system during the life span, resulting in an age-related qualitative-quantitative decline of immune cells and cytokines. A growing body of evidence in the international literature is highlighting the etiopathogenetic role of skin immunosenescence in the onset of various dermatologic conditions. Skin immunosenescence also serves as an interesting watershed for the onset of system-wide conditions in the context of allergic inflammation. Moreover, in recent years, an increasingly emerging and fascinating etiopathogenetic parallelism has been observed between some mechanisms of immunosenescence, both at cutaneous and systemic sites. This would help to explain the occurrence of apparently unconnected comorbidities. Throughout our review, we aim to shed light on emerging immunosenescent mechanisms shared between dermatologic disorders and other organ-specific diseases in the context of a more extensive discussion on the etiopathogenetic role of skin immunosenescence. A promising future perspective would be to focus on better understanding the mutual influence between skin and host immunity, as well as the influence of high inter-individual variability on immunosenescence/inflammaging. This can lead to a more comprehensive "immunobiographic" definition of each individual.

COVID-19 in Adult Patients with Hematological Malignancies-Lessons Learned after Three Years of Pandemic

The COVID-19 pandemic is undoubtedly the most difficult health challenge of the 21st century with more than 600 million laboratory-confirmed SARS-CoV-2 infections and over 6.5 million deaths worldwide. The coronavirus pandemic contributed to rapid development of mRNA vaccines, which, along with new antiviral drugs, have been the subject of extensive research for many decades. Nevertheless, elderly, multi-morbid and immunocompromised patients continue to face a more severe clinical course and a higher risk of death from COVID-19, even now that the risk of COVID-19 in the general population is significantly reduced due to the introduction of global vaccination strategies. In this paper, we present the mechanisms of increased susceptibility to infectious complications and the evolution of the clinical course of COVID-19 in patients with hematological malignancies, taking into account the mutation of the virus and the introduction of vaccines and new antiviral drugs. We also present current recommendations for prophylactic and therapeutic management in patients with hematological malignancies.

Immunology of Aging: the Birth of Inflammaging

The inflammaging concept was introduced in 2000 by Prof. Franceschi. This was an evolutionary or rather a revolutionary conceptualization of the immune changes in response to a lifelong stress. This conceptualization permitted to consider the lifelong proinflammatory process as an adaptation which could eventually lead to either beneficial or detrimental consequences. This dichotomy is influenced by both the genetics and the environment. Depending on which way prevails in an individual, the outcome may be healthy longevity or pathological aging burdened with aging-related diseases. The concept of inflammaging has also revealed the complex, systemic nature of aging. Thus, this conceptualization opens the way to consider age-related processes in their complexity, meaning that not only the process but also all counter-processes should be considered. It has also opened the way to add new concepts to the original one, leading to better understanding of the nature of inflammaging and of aging itself. Finally, it showed the way towards potential multimodal interventions involving a holistic approach to optimize the aging process towards a healthy longevity.

[Cytomegalovirus disease in immunosuppressed patients with necrotizing pauci-immune glomerulonephritis]

INTRODUCTION

Renal involvement due to necrotizing pauci-immune glomerulonephritis (PIGN) associated with small vessel vasculitis requires the use of immunosuppressive. Associated side effects include an increased risk of infectious processes, such as cytomegalovirus (CMV) disease; therefore, there are no recommendations on its management in the various clinical practice guidelines (CPG).

OBJECTIVE

To study the incidence of CMV disease and its determinants.

PATIENTS AND METHODS

Patients with histological diagnosis of necrotizing pauci-immune glomerulonephritis in the last 10 years, who were determined the viral load of CMV, analyzing the determinants of its occurrence.

RESULTS

Forty-four biopsies were performed during the study period. Eleven patients (25%) developed CMV disease; all had received immunosuppressive treatment. Four (30.8%) died during admission. The determinants of CMV disease were age (for every 10 years OR: 3.0, 95% CI: 1.0-8.9, p = 0.012), and plasma albumin (for each g/L OR: 0.8, 95% CI: 0.6-1.0, p = 0.012).

CONCLUSIONS

The incidence of CMV disease in immunocompromised patients due to PIGN is high, with high mortality. It would be necessary to include strategies in the CPGs to prevent it.

Vitamin D, Cellular Senescence and Chronic Kidney Diseases: What Is Missing in the Equation?

As life expectancy increases in many countries, the prevalence of age-related diseases also rises. Among these conditions, chronic kidney disease is predicted to become the second cause of death in some countries before the end of the century. An important problem with kidney diseases is the lack of biomarkers to detect early damage or to predict the progression to renal failure. In addition, current treatments only retard kidney disease progression, and better tools are needed. Preclinical research has shown the involvement of the activation of cellular senescence-related mechanisms in natural aging and kidney injury. Intensive research is searching for novel treatments for kidney diseases as well as for anti-aging therapies. In this sense, many experimental shreds of evidence support that treatment with vitamin D or its analogs can exert pleiotropic protective effects in kidney injury. Moreover, vitamin D deficiency has been described in patients with kidney diseases. Here, we review recent evidence about the relationship between vitamin D and kidney diseases, explaining the underlying mechanisms of the effect of vitamin D actions, with particular attention to the modulation of cellular senescence mechanisms.

Bibliometric and visualization analysis of global research trends on immunosenescence (1970-2021)

BACKGROUND

Immunosenescence, the aging of the immune system, leads to a decline in the body's adaptability to the environment and plays an important role in various diseases. Immunosenescence has been widely studied in recent years. However, to date, no relevant bibliometric analyses have been conducted. This study aimed to analyze the foundation and frontiers of immunosenescence research through bibliometric analysis.

METHODS

Articles and reviews on immunosenescence from 1970 to 2021 were obtained from the Web of Science Core Collection. Countries, institutions, authors, journals, references, and keywords were analyzed and visualized using VOSviewer and CiteSpace. The R language and Microsoft Excel 365 were used for statistical analyses.

RESULTS

In total, 3763 publications were included in the study. The global literature on immunosenescence research has increased from 1970 to 2021. The United States was the most productive country with 1409 papers and the highest H-index. Italy had the highest average number of citations per article (58.50). Among the top 10 institutions, 50 % were in the United States. The University of California was the most productive institution, with 159 articles. Kroemer G, Franceschi C, Goronzy JJ, Solana R, and Fulop T were among the top 10 most productive and co-cited authors. Experimental Gerontology (n = 170) published the most papers on immunosenescence. The analysis of keywords found that current research focuses on "inflammaging", "gut microbiota", "cellular senescence", and "COVID-19".

CONCLUSIONS

Immunosenescence research has increased over the years, and future cooperation and interaction between countries and institutions must be expanded. The connection between inflammaging, gut microbiota, age-related diseases, and immunosenescence is a current research priority. Individualized treatment of immunosenescence, reducing its negative effects, and promoting healthy longevity will become an emerging research direction.

Vaccines for the Prevention of Coronavirus Disease 2019 in Older Adults

Institutionalized and community-dwelling older adults have been greatly impacted by the coronavirus disease 2019 (COVID-19) pandemic with increased morbidity and mortality. The advent of vaccines and their widespread use in this population has brought about a dramatic turnaround in COVID-19 outcomes. The immunogenicity and effectiveness of the various vaccine options worldwide are discussed. Optimization of vaccine usage will still be important to maximize protection due to reduced initial immunity, development of variant strains, and fading of immunity over time. There are also lessons learned specific to older populations for future pandemics of novel pathogens.

Sex/gender-related differences in inflammaging

Geroscience puts mechanisms of aging as a driver of the most common age-related diseases and dysfunctions. Under this perspective, addressing the basic mechanisms of aging will produce a better understanding than addressing each disease pathophysiology individually. Worldwide, despite greater functional impairment, life expectancy is higher in women than in men. Gender differences in the prevalence of multimorbidity lead mandatory to the understanding of the mechanisms underlying gender-related differences in multimorbidity patterns and disability-free life expectancy. Extensive literature suggested that inflammaging is at the crossroad of aging and age-related diseases. In this review, we highlight the main evidence on sex/gender differences in the mechanisms that foster inflammaging, i.e. the age-dependent triggering of innate immunity, modifications of adaptive immunity, and accrual of senescent cells, underpinning some biomarkers of inflammaging that show sex-related differences. In the framework of the "gender medicine perspective", we will also discuss how sex/gender differences in inflammaging can affect sex differences in COVID-19 severe outcomes.

Autopsies Revealed Pathological Features of COVID-19 in Unvaccinated vs. Vaccinated Patients

Background: In Italy, by the end of 2021, a new pandemic wave led to increased hospitalizations and death, even in some vaccinated people. We aimed to investigate the death of COVID-19-vaccinated patients who acquired infection and developed severe disease, and to assess differences with fatal COVID-19 in unvaccinated subjects by studying the pathological events triggered by SARS-CoV-2. Methods: Detailed autoptic examination was performed on five fully vaccinated compared to five unvaccinated patients. Histopathological analysis focused on the lung and heart, the two major affected organs. Results: COVID-19 caused, or contributed to death, in all the unvaccinated cases. By contrast, in vaccinated group, pre-existing pathologies played a major role, and death was not COVID-19-related in four out of five patients. These patients did not show the histological features of SARS-CoV-2 lung damage. Diffuse inflammatory macrophages infiltration recently emerged as the main feature of COVID-19 cardiac injury. Interestingly, the most striking difference between the two groups was the absence of increased macrophage infiltration in the heart of vaccinated patients. Conclusions: Results of this study confirm the efficacy of anti-SARS-CoV-2 vaccination in protecting organs from injury and support the need to maintain an adequate immune response by booster dose administration.

Effect of COVID-19 Vaccination on the In-Hospital Prognosis of Patients Admitted during Delta and Omicron Waves in Italy

All-cause mortality related to the SARS-CoV-2 infection has declined from the first wave to subsequent waves, probably through vaccination programs and the availability of effective antiviral therapies. Our study aimed to evaluate the impact of the SARS-CoV-2 vaccination on the prognosis of infected patients. Overall, we enrolled 545 subjects during the Delta variant wave and 276 ones during the Omicron variant wave. Data were collected concerning vaccination status, clinical parameters, comorbidities, lung involvement, laboratory parameters, and pharmacological treatment. Outcomes were admission to the intensive care unit (ICU) and 30-day all-cause mortality. Overall, the final sample included 821 patients with a mean age of 62 ± 18 years [range 18-100], and 59% were men. Vaccinated patients during the Delta wave were 37% (over ¾ with two doses), while during the Omicron wave they were 57%. Vaccinated patients were older (68 vs. 57 years), and 62% had at least one comorbidity Admission to the ICU was 20%, and the mortality rate at 30 days was 14%. ICU admissions were significantly higher during the Delta wave than during Omicron (OR 1.9, 95% CI 1.2-3.1), while all-cause mortality did not differ. Unvaccinated patients had a higher risk of ICU admission (OR 2.0, 95% CI 1.3-3.1) and 30-day all-cause mortality (OR 1.7, 95% CI 1.3-2.7). Results were consistent for both Delta and Omicron variants. Overall, vaccination with at least two doses was associated with a reduced need for ICU admission. Even one shot of the vaccine was associated with a significantly reduced 30-day mortality.

Severely ill and high-risk COVID-19 patients exhibit increased peripheral circulation of CD62L+ and perforin+ T cells

Introduction

The emergence of SARS-CoV-2, which causes COVID-19, has led to over 400 million reported cases worldwide. COVID-19 disease ranges from asymptomatic infection to severe disease and may be impacted by individual immune differences.

Methods

We used multiparameter flow cytometry to compare CD4+ and CD8+ T cell responses in severe (ICU admitted) and non-severe (admitted to observational unit) hospitalized COVID-19 patients.

Results

We found that patients with severe COVID- 19 had greater frequencies of CD4+ T cells expressing CD62L compared to non-severe patients and greater frequencies of perforin+ CD8+ T cells compared to recovered patients. Furthermore, greater frequencies of CD62L+ CD4+ and CD8+ T cells were seen in severely ill diabetic patients compared to non-severe and non-diabetic patients, and increased CD62L+ CD4+ T cells were also seen in severely ill patients with hypertension.

Discussion

This is the first report to show that CD62L+ T cells and perforin+ T cells are associated with severe COVID-19 illness and are significantly increased in patients with high-risk pre-existing conditions including older age and diabetes. These data provide a potential biological marker for severe COVID-19.

Exergame and/or conventional training-induced neuroplasticity and cognitive improvement by engaging epigenetic and inflammatory modulation in elderly women: A randomized clinical trial

OBJECTIVE

To evaluate the acute and long-term impact of exergaming (EXE) and conventional therapy (CON) in the peripheral levels of brain-derived neurotrophic factor (BDNF), inflammatory markers (interleukin [IL]-1b, IL-6, IL-8, and tumor necrosis factor-alpha [TNF-α]) and epigenetic mechanisms (global histone H3 and H4 acetylation levels in mononuclear cells) of healthy elderly women. We also evaluated the effect of intervention on cognitive performance in these individuals.

METHODS

Twenty-two elderly women were randomly assigned into two groups: EXE (n = 12) and CON (n = 10). Both interventions were performed twice a week for 6 weeks (12 sessions). Blood samples were obtained before intervention, after the first session, and 1 hour after the last session. Cognitive performance was evaluated before and after intervention.

RESULTS

Both EXE and CON interventions ameliorated cognitive performance, improved inflammatory profile, enhanced BDNF levels, and induced histone H4 and H3 hyperacetylation status in elderly women.

CONCLUSION

Our study demonstrated that the proposed interventions can be considered important strategies capable of promoting cognitive improvement in healthy elderly women. The acetylation status of histones and inflammatory cytokines are possible molecular mechanisms that mediate this beneficial response, being distinctly modulated by acute and long-term exposure.

Translational research into frailty from bench to bedside: Salivary biomarkers for inflammaging

Frailty is a complex physiological syndrome associated with adverse ageing and decreased physiological reserves. Frailty leads to cognitive and physical disability and is a significant cause of morbidity, mortality and economic costs. The underlying cause of frailty is multifaceted, including immunosenescence and inflammaging, changes in microbiota and metabolic dysfunction. Currently, salivary biomarkers are used as early predictors for some clinical diseases, contributing to the effective prevention and treatment of diseases, including frailty. Sample collection for salivary analysis is non-invasive and simple, which are paramount factors for testing in the vulnerable frail population. The aim of this review is to describe the current knowledge on the association between frailty and the inflammatory process and discuss methods to identify putative biomarkers in salivary fluids to predict this syndrome. This study describes the relationship between i.-inflammatory process and frailty; ii.-infectious, chronic, skeletal, metabolic and cognitive diseases with inflammation and frailty; iii.-inflammatory biomarkers and salivary fluids. There is a limited number of previous studies focusing on the analysis of inflammatory salivary biomarkers and frailty syndrome; hence, the study of salivary fluids as a source for biomarkers is an open area of research with the potential to address the increasing demands for frailty-associated biomarkers.

Sialic acid-mediated photochemotherapy enhances infiltration of CD8+ T cells from tumor-draining lymph nodes into tumors of immunosenescent mice

Immunoscenescence plays a key role in the initiation and development of tumors. Furthermore, immunoscenescence also impacts drug delivery and cancer therapeutic efficacy. To reduce the impact of immunosenescence on anti-tumor therapy, this experimental plan aimed to use neutrophils with tumor tropism properties to deliver sialic acid (SA)-modified liposomes into the tumor, kill tumor cells via SA-mediated photochemotherapy, enhance infiltration of neutrophils into the tumor, induce immunogenic death of tumor cells with chemotherapy, enhance infiltration of CD8⁺ T cells into the tumor-draining lymph nodes and tumors of immunosenescent mice, and achieve SA-mediated photochemotherapy. We found that CD8⁺ T cell and neutrophil levels in 16-month-old mice were significantly lower than those in 2- and 8-month-old mice; 16-month-old mice exhibited immunosenescence. The anti-tumor efficacy of SA-mediated non-photochemotherapy declined in 16-month-old mice, and tumors recurred after scabbing. SA-mediated photochemotherapy enhanced tumor infiltration by CD8⁺ T cells and neutrophils, induced crusting and regression of tumors in 8-month-old mice, inhibited metastasis and recurrence of tumors and eliminated the immunosenescence-induced decline in antitumor therapeutic efficacy in 16-month-old mice via the light-heat-chemical-immunity conversion.

Immune cell populations differ in patients undergoing revision total knee arthroplasty for arthrofibrosis

Arthrofibrosis following total knee arthroplasty (TKA) is a debilitating condition typically diagnosed based on clinical findings. To gain insight into the histopathologic immune cell microenvironment of arthrofibrosis, we assessed the extent of tissue fibrosis and quantified immune cell populations in specific tissue regions of the posterior capsule. We investigated specimens from three prospectively-collected, matched cohorts, grouped as patients receiving a primary TKA for osteoarthritis, revision TKA for arthrofibrosis, and revision TKA for non-arthrofibrotic, non-infectious reasons. Specimens were evaluated using hematoxylin and eosin staining, picrosirius red staining, immunofluorescence, and immunohistochemistry with Aperio®-based digital image analysis. Increased collagen deposition and increased number of α-SMA/ACTA2 expressing myofibroblasts were present in the arthrofibrosis group compared to the two non-arthrofibrotic groups. CD163 + macrophages were the most abundant immune cell type in any capsular sample with specific enrichment in the synovial tissue. CD163 + macrophages were significantly decreased in the fibrotic tissue region of arthrofibrosis patients compared to the patients with primary TKA, and significantly increased in adipose tissue region of arthrofibrotic specimens compared to non-arthrofibrotic specimens. Synovial CD117 + mast cells were significantly decreased in arthrofibrotic adipose tissue. Together, these findings inform diagnostic and targeted therapeutic strategies by providing insight into the underlying pathogenetic mechanisms of arthrofibrosis.

Effects of Oleuropein and Hydroxytyrosol on Inflammatory Mediators: Consequences on Inflammaging

Aging is associated with a low-grade, systemic inflammatory state defined as "inflammaging", ruled by the loss of proper regulation of the immune system leading to the accumulation of pro-inflammatory mediators. Such a condition is closely connected to an increased risk of developing chronic diseases. A number of studies demonstrate that olive oil phenolic compound oleuropein and its derivative hydroxytyrosol contribute to modulating tissue inflammation and oxidative stress, thus becoming attractive potential candidates to be used in the context of nutraceutical interventions, in order to ameliorate systemic inflammation in aging subjects. In this review, we aim to summarize the available data about the anti-inflammatory properties of oleuropein and hydroxytyrosol, discussing them in the light of molecular pathways involved in the synthesis and release of inflammatory mediators in inflammaging.

Efficacy and Safety of COVID-19 Vaccination in Older Adults: A Systematic Review and Meta-Analysis

Objective: To analyze the differences in efficacy and safety of different types of novel coronavirus pneumonia (COVID-19) vaccines in different age groups (young adults and elderly). Methods: Randomized controlled trials (RCTs) on COVID-19 vaccine in PubMed, Embase, Web of Science, and Cochrane library were searched by computer, and eight eligible studies were analyzed. Meta-analysis was performed using Stata 16.0 and RevMan5.4 software. Results: The mean geometric titer (GMT) of the virus in the elderly was significantly higher than that in the placebo group (SMD = 0.91, 95% CI (0.68, 1.15), p < 0.01), presenting no obvious difference compared with the young adults (SMD = 0.19, 95% CI (0.38, 0.01), p = 0.06). Meanwhile, the effect of multiple vaccinations was better than that of single vaccination (SMD = 0.83, 95% CI (0.33, 1.34), p < 0.01). However, the number of adverse events (AEs) in the elderly was lower than that in the young adults (OR = 0.35, 95% CI (0.29, 0.42), p < 0.01). Conclusions: The immunization effect of COVID-19 vaccine in the elderly is obvious, especially after multiple vaccinations, and the incidence of AEs in the elderly is low, which proves that the vaccination of the elderly is safe and effective.

Immune system modulation in aging: Molecular mechanisms and therapeutic targets

The function of the immune system declines during aging, compromising its response against pathogens, a phenomenon termed as "immunosenescence." Alterations of the immune system undergone by aged individuals include thymic involution, defective memory T cells, impaired activation of naïve T cells, and weak memory response. Age-linked alterations of the innate immunity comprise perturbed chemotactic, phagocytic, and natural killing functions, as well as impaired antigen presentation. Overall, these alterations result in chronic low-grade inflammation (inflammaging) that negatively impacts health of elderly people. In this review, we address the most relevant molecules and mechanisms that regulate the relationship between immunosenescence and inflammaging and provide an updated description of the therapeutic strategies aimed to improve immunity in aged individuals.

Sex differences in Guillain Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and experimental autoimmune neuritis

Guillain Barré syndrome (GBS) and its variants, and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP and its variants, are regarded as immune mediated neuropathies. Unlike in many autoimmune disorders, GBS and CIDP are more common in males than females. Sex is not a clear predictor of outcome. Experimental autoimmune neuritis (EAN) is an animal model of these diseases, but there are no studies of the effects of sex in EAN. The pathogenesis of GBS and CIDP involves immune response to non-protein antigens, antigen presentation through non-conventional T cells and, in CIDP with nodopathy, IgG4 antibody responses to antigens. There are some reported sex differences in some of these elements of the immune system and we speculate that these sex differences could contribute to the male predominance of these diseases, and suggest that sex differences in peripheral nerves is a topic worthy of further study.

Immunosenescence profiles of lymphocyte compartments and multiple long-term conditions (multimorbidity) in very old adults: The Newcastle 85+ Study

Immunosenescence, a decline in immune system function, has been linked to several age-related diseases and ageing syndromes. Very old adults (aged ≥ 85 years) live with multiple long-term conditions (MLTC, also known as multimorbidity)-a complex phenomenon of poor health defined by either counts, indices, or patterns, but little is known about the relationship between an ageing immune system and MLTC in this age group. We utilised baseline data from the Newcastle 85+ Study to investigate the associations between previously defined immunosenescence profiles of lymphocyte compartments and MLTC counts and patterns (from 16 chronic diseases/ageing syndromes). Seven hundred and three participants had MLTC and complete data for all 16 conditions, a median and mean of 5 (range 2-11) and 62.2% had ≥ 5 conditions. Three distinct MLTC patterns emerged by clustering: Cluster 1 ('Low frequency cardiometabolic-cerebrovascular diseases', n = 209), Cluster 2 ('High ageing syndromes-arthritis', n = 240), and Cluster 3 ('Hypertensive-renal impairment', n = 254). Although having a more senescent phenotype, characterised by higher frequency of CD4 and CD8 senescence-like effector memory cells and lower CD4/CD8 ratio, was not associated with MLTC compared with less senescent phenotype, the results warrant further investigation, including whether immunosenescence drives change in MLTC and influences MLTC severity in late adulthood.

Global Effect of COVID-19 Pandemic on Cancer Patients and its Treatment: A Systematic Review

Background

At a global level, the COVID-19 disease outbreak has had a major impact on health services and has induced disruption in routine care of health institutions, exposing cancer patients to severe risks. To provide uninterrupted tumor treatment throughout a pandemic lockdown is a major obstacle. Coronavirus disease (COVID-19) and its causative virus, SARS-CoV-2, stance considerable challenges for the management of oncology patients. COVID-19 presents particularly severe respiratory and systemic infection in aging and immunosuppressed individuals, including patients with cancer.

Objective

In the present review, we focused on emergent evidence from cancer sufferers that have been contaminated with COVID-19 and cancer patients who were at higher risk of severe COVID-19, and indicates that anticancer treatment may either rise COVID-19 susceptibility or have a duple therapeutic impact on cancer as well as COVID-19; moreover, how SARS-CoV-2 infection impacts cancer cells. Also, to assess the global effect of the COVID-19 disease outbreak on cancer and its treatment.

Methods

A literature survey was conducted using PubMed, Web of Science (WOS), Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and VIral Protein domain DataBase (VIP DB) between Dec 1, 2019 and Sep 23, 2021, for studies on anticancer treatments in patients with COVID-19. The characteristics of the patients, treatment types, mortality, and other additional outcomes were extracted and pooled for synthesis.

Results

This disease has a huge effect on sufferers who have cancer(s). Sufferers of COVID-19 have a greater percentage of tumor diagnoses than the rest of the population. Likewise, cancer and highest proportion is lung cancer sufferers are more susceptible to COVID-19 constriction than the rest of the population.

Conclusion

Sufferers who have both COVID-19 and tumor have a considerably elevated death risk than single COVID-19 positive patients overall. During the COVID-19 pandemic, there was a reduction in the screening of cancer and detection, and also deferral of routine therapies, which may contribute to an increase in cancer mortality there in future.

The DARC Side of Inflamm-Aging: Duffy Antigen Receptor for Chemokines (DARC/ACKR1) as a Potential Biomarker of Aging, Immunosenescence, and Breast Oncogenesis among High-Risk Subpopulations

The proclivity of certain pre-malignant and pre-invasive breast lesions to progress while others do not continues to perplex clinicians. Clinicians remain at a crossroads with effectively managing the high-risk patient subpopulation owing to the paucity of biomarkers that can adequately risk-stratify and inform clinical decisions that circumvent unnecessary administration of cytotoxic and invasive treatments. The immune system mounts the most important line of defense against tumorigenesis and progression. Unfortunately, this defense declines or "ages" over time-a phenomenon known as immunosenescence. This results in "inflamm-aging" or the excessive infiltration of pro-inflammatory chemokines, which alters the leukocyte composition of the tissue microenvironment, and concomitant immunoediting of these leukocytes to diminish their antitumor immune functions. Collectively, these effects can foster the sequelae of neoplastic transformation and progression. The erythrocyte cell antigen, Duffy antigen receptor for chemokines(DARC/ACKR1), binds and internalizes chemokines to maintain homeostatic levels and modulate leukocyte trafficking. A negative DARC status is highly prevalent among subpopulations of West African genetic ancestry, who are at higher risk of developing breast cancer and disease progression at a younger age. However, the role of DARC in accelerated inflamm-aging and malignant transformation remains underexplored. Herein, we review compelling evidence suggesting that DARC may be protective against inflamm-aging and, therefore, reduce the risk of a high-risk lesion progressing to malignancy. We also discuss evidence supporting that immunotherapeutic intervention-based on DARC status-among high-risk subpopulations may evade malignant transformation and progression. A closer look into this unique role of DARC could glean deeper insight into the immune response profile of individual high-risk patients and their predisposition to progress as well as guide the administration of more "cyto-friendly" immunotherapeutic intervention to potentially "turn back the clock" on inflamm-aging-mediated oncogenesis and progression.

Influenza Vaccination Reduces the Risk of Liver Cancer in Patients with Chronic Kidney Disease: A Nationwide Population-Based Cohort Study

Previous studies have indicated that influenza vaccination reduces the development of lung cancer. However, the protective effects of influenza vaccination on primary liver cancer in patients with chronic kidney disease (CKD) are unclear. This cohort study identified 12,985 patients aged at least 55 years who had received a diagnosis of CKD between 1 January 2001 and 31 December 2012 from the National Health Insurance Research Database of Taiwan. The patients were classified according to vaccination status. Propensity score matching was used to reduce selection bias. Cox proportional hazards regression analysis was used to evaluate the correlation between influenza vaccination and primary liver cancer in patients with CKD. The prevalence of primary liver cancer was lower in patients with CKD who had received an influenza vaccine (adjusted hazard ratio: 0.45, 95% confidence interval [CI]: 0.35−0.58, p < 0.001). The protective effects were observed regardless of sex, age, and comorbidities. Moreover, dose-dependent protective effects were observed. In the subgroup analysis, where the patients were classified by the number of vaccinations received, the adjusted hazard ratios for 1, 2−3, and ≥4 vaccinations were 0.86 (95% CI: 0.63−1.17), 0.45 (95% CI: 0.31−0.63), and 0.21 (95% CI: 0.14−0.33), respectively. In conclusion, influenza vaccination was associated with a lower incidence of liver cancer in patients with CKD.

Senescence of the immune defences and reproductive trade-offs in females of the mealworm beetle, Tenebrio molitor

In the theory of ageing, it has been assumed that ageing is associated with a decline in somatic defences, including the immune system, as a consequence of a trade-off with reproduction. While overall immunity suffers from age-related deterioration (immune senescence), the different components of the immune response appear to age differently. It is also likely that investment among the many arms of the immune system and reproduction with age is finely adjusted to the organisms' reproductive strategy. We investigated this possibility in females of Tenebrio molitor, a species of long-lived insect with reproductive strategies similar to those of long-lived mammals. We specifically tested the effects of immunological challenges imposed early or late in adult life on immune pathway activation as well as fertility early and late in life. We found complex patterns of changes in immune defences with age and age-specific immune challenges with contrasted relationships with female reproduction. While cellular and enzymatic defences showed signs of ageing, they did not trade-off with reproduction. By contrast, the induced antibacterial immune response was found to be unaffected by age and to be highly connected to female fecundity. These findings suggest that these immunological pathways have different functions with regard to female ageing in this insect species.

The Four Ws of the Fourth Dose COVID-19 Vaccines: Why, Who, When and What

With the emergence of SARS-CoV-2 variants, vaccine breakthrough is a major public health concern. With evidence of reduced neutralizing antibody activity against Omicron variants and fading antibody level after the third-dose booster vaccine, there are suggestions of a fourth-dose booster vaccine. In this review, the benefits of a fourth-dose booster is evaluated from four perspectives, including the effectiveness of the booster dose against virus variants (Why), susceptible groups of individuals who may benefit from additional booster dose (Who), selection of vaccine platforms to better enhance immunity (What) and appropriate intervals between the third and fourth booster dose (When). In summary, a fourth dose can temporarily boost the immune response against SARS-CoV-2 variants and can be considered for specific groups of individuals. A heterologous vaccine strategy using mRNA vaccine in individuals primed with inactivated vaccine may boost immunity against variants. The timing of the fourth dose should be individualized but an interval of 4 months after the third-dose booster is appropriate. A universal fourth booster dose is not necessary.

Calibrating a Comprehensive Immune Age Metric to Analyze the Cross Sectional Age-Related Decline in Cardiorespiratory Fitness

Cardiorespiratory fitness (CRF) is essential for sustained work ability in good health, but declines with aging, as does the functionality of the immune system, the latter process commonly referred to as immunosenescence. This study aimed to compare the capacity of immunosenescence biomarkers with chronological age for predicting low CRF in a cross-sectional sample recruited from the regional working population. CRF was determined by submaximal bicycle ergometer testing in a cross-sectional sample of 597 volunteers aged 20-70 years from the 'Dortmund Vital Study' (DVS, ClinicalTrials.gov Identifier: NCT05155397). Low CRF was scored if the ergometer test was not completed due to medical reasons or if the power output projected to a heart rate of 130 bpm divided by body mass was below sex-specific reference values of 1.25 W/kg for females and 1.5 W/kg for males, respectively. In addition to established biomarkers of immunosenescence, we calibrated a comprehensive metric of immune age to our data and compared its predictive capacity for low CRF to chronological age, while adjusting our analysis for the influence of sex, obesity, and the level of regular physical activity, by applying univariate and multiple logistic regression. While obesity, low physical activity, chronological and immune age were all associated with increased probability for low CRF in univariate analyses, multiple logistic regression revealed that obesity and physical activity together with immune age, but not chronological age, were statistically significant predictors of low CRF outcome. Sex was non-significant due to the applied sex-specific reference values. These results demonstrate that biological age assessed by our immunological metric can outperform chronological age as a predictor for CRF and indicate a potential role for immunosenescence in explaining the inter-individual variability of the age-related decline in cardiorespiratory fitness.

Immunodominance hierarchy after seasonal influenza vaccination

Current influenza vaccines elicit humoral immune responses against the hemagglutinin (HA) protein of influenza viruses. Different antigenic sites have been identified in the HA head as the main target of hemagglutination inhibition (HAI) antibodies (Sb, Sa, Cb, Ca1 and Ca2). To determine immunodominance (ID) of each site, we performed HAI assays against a panel of mutant viruses, each one lacking one of the classically defined antigenic sites and compared it to wild type (Wt). Agglutinating antibodies were measured before and after vaccination in two different regimens: Quadrivalent Influenza Vaccine (QIV) in young adults; or Adjuvanted Trivalent influenza Vaccine (ATIV) in elderly. Our results showed abs before vaccination were significantly reduced against all antigenic sites in the elderly and only against Sb and Ca2 in young adults compared to the Wt. Humoral response to vaccination was significantly reduced against all viruses compared to the Wt for the ATIV and only against Sb and Ca2 for the QIV. The strongest reduction was observed in all cases against Sb followed by Ca2. We concluded that ID profile was clearly dominated by Sb followed by Ca2. Additionally, the antibody response evolved with age, increasing the response towards less immunodominant epitopes of HA head. Adjuvants can positively influence ID hierarchy broadening responses towards multiple antigenic sites of HA head.

Composition of the infiltrating immune cells in the brain of healthy individuals: effect of aging

Immune cells infiltrating the central nervous system (CNS) are involved in the defense against invading microbes as well as in the pathogenesis of neuroinflammatory diseases. In these conditions, the presence of several types of immune and inflammatory cells have been demonstrated. However, some studies have also reported low amounts of immune cells that have been detected in the CNS of healthy individuals, but the cell types present have not been systematically analyzed. To do this, we now used brain samples from The Genotype- Tissue Expression (GTEx) project to analyze the relative abundance of 22 infiltrating leukocyte types using a digital cytometry tool (CIBERSORTx). To characterize cell proportions in different parts of the CNS, samples from 13 different anatomic brain regions were used. The data obtained demonstrated that several leukocyte types were present in the CNS. Six leukocyte types (CD4 memory resting T cells, M0 macrophages, plasma cells, CD8 T cells, CD4 memory activated T cells, and monocytes) were present with a proportion higher than 0.05, i.e. 5%. These six cell types were present in most brain regions with only insignificant variation. A consistent association with age was seen with monocytes, CD8 T cells, and follicular helper T cells. Taken together, these data show that several infiltrating immune cell types are present in the non-diseased CNS tissue and that the proportions of infiltrating cells are affected by age in a manner that is consistent with literature on immunosenecence and inflammaging.

A comparative review on the anti-nutritional factors of herbal tea concoctions and their reduction strategies

Tea is an important beverage consumed worldwide. Of the different types of tea available, herbal tea is an important beverage consumed owing to its popularity as a drink and stress relieving factors, several different herbal concoctions made from seeds, leaves, or roots are currently consumed and sold as herbal teas. The herbal teas are not the usual tea but "tisanes." They are caffeine free and popular for their medicinal property or immune boosters. Herbal tea formulations are popularly sold and consumed by millions owing to their health benefits as they are rich in antioxidants and minerals. However, plants are also known to contain toxic and anti-nutritional factors. Anti-nutritional factors are known to interfere with the metabolic process and hamper the absorption of important nutrients in the body. These anti-nutritional factors include saponins, tannins, alkaloids, oxalates, lectins, goitrogens, cyanogens, and lethogens. These chemicals are known to have deleterious effects on human health. Therefore, it is important to understand and assess the merits and demerits before consumption. Also, several techniques are currently used to process and reduce the anti-nutrients in foods. This review is focused on comparing the contents of various anti-nutritional factors in some underutilized plants of North-East India used as herbal tea along with processing methods that can be used to reduce the level of these anti-nutrients.

Age-related macular degeneration and myeloproliferative neoplasms - A common pathway

DANSK RESUMÉ (DANISH SUMMARY): Aldersrelateret makuladegeneration (AMD) er den hyppigste årsag til uopretteligt synstab og blindhed i højindkomstlande. Det er en progredierende nethindesygdom som gradvist fører til ødelaeggelse af de celler som er ansvarlige for vores centralsyn. De tidlige stadier er ofte asymptomatiske, imens senstadie AMD, som opdeles i to former, neovaskulaer AMD (nAMD) og geografisk atrofi (GA), begge udviser gradvist synstab, dog generelt med forskellig hastighed. Tidlig AMD er karakteriseret ved tilstedevaerelsen af druser og pigmentforandringer i nethinden mens nAMD og GA udviser henholdsvis karnydannelse i og atrofi af nethinden. AEtiologien er multifaktoriel og udover alder omfatter patogenesen miljø- og genetiske risikofaktorer. Forskning har specielt fokuseret på lokale forandringer i øjet hvor man har fundet at inflammation spiller en betydelig rolle for udviklingen af sygdommen, men flere studier tyder også på at systemiske forandringer og specielt systemisk inflammation spiller en vaesentlig rolle i patogenesen. De Philadelphia-negative myeloproliferative neoplasier (MPNs) er en gruppe af haematologiske kraeftsygdomme med en erhvervet genetisk defekt i den tidlige pluripotente stamcelle som medfører en overproduktion af en eller flere af blodets modne celler. Sygdommene er fundet at udvikle sig i et biologisk kontinuum fra tidligt cancerstadie, essentiel trombocytose (ET) over polycytaemi vera (PV) og endelig til det sene myelofibrose stadie (PMF). Symptomer hos disse patienter skyldes isaer den aendrede sammensaetning af blodet, hyperviskositet, kompromitteret mikrocirkulation og nedsat vaevsgennemblødning. Den øgede morbiditet og mortalitet beror i høj grad på tromboembolier, blødninger og leukemisk transformation. En raekke mutationer som driver MPN sygdommene er identificeret, bl.a. JAK2V617F-mutationen som medfører en deregulering JAK/STAT signalvejen, der bl.a. har betydning for cellers vaekst og overlevelse. Et tidligere stort registerstudie har vist at patienter med MPNs har en øget risiko for neovaskulaer AMD og et pilotstudie har vist øget forekomst af intermediaer AMD. Dette ønsker vi at undersøge naermere i et større studie i dette Ph.d.- projekt. Flere studier har også vist at kronisk inflammation spiller en vigtig rolle for både initiering og udvikling af den maligne celleklon hos MPNs og herfra er en "Human Inflammationsmodel" blevet udviklet. Siden er MPN sygdommene blevet anvendt som "model sygdomme" for en tilsvarende inflammationsmodel for udvikling af Alzheimers sygdom. I dette Ph.d.-projekt vil vi tilsvarende forsøge at undersøge systemisk inflammation i forhold til forekomst af druser. Det vil vi gøre ved at sammenligne systemiske immunologiske markører som tidligere er undersøgt hos patienter med AMD og sammenligne med MPN. Specielt er vi interesseret i systemiske immunologiske forskelle på patienter med MPN og druser (MPNd) og MPN med normale nethinder (MPNn). Denne afhandling består af to overordnede studier. I Studie I, undersøgte vi forekomsten af retinale forandringer associeret med AMD hos 200 patienter med MPN (artikel I). Studie II, omhandlede immunologiske ligheder ved AMD og MPN, og var opdelt i yderligere tre delstudier hvor vi undersøgte hhv. systemiske markører for inflammation, aldring og angiogenese (artikel II, III og IV). Vi undersøgte markørerne i fire typer af patienter: nAMD, intermediaer AMD (iAMD), MPNd og MPNn. Undersøgelsen af forskelle mellem MPNd og MPNn, vil gøre det muligt at identificere forandringer i immunsystemet som kunne vaere relevante for AMD-patogenesen. Vi vil endvidere sammenholde resultaterne for patienter med MPN med patienter som har iAMD og nAMD. I studie I (Artikel I) fandt vi at patienter med MPN har en signifikant højere praevalens af store druser og AMD tidligere i livet sammenlignet med estimater fra tre store befolkningsundersøgelser. Vi fandt også at forekomst af druser var associeret med højere neutrofil-lymfocyt ratio, hvilket indikerer et højere niveau af kronisk inflammation i patienterne med druser sammenlignet med dem uden druser. I studie II (Artikel II, III og IV) fandt vi flere immunologiske forskelle mellem patienter med MPNd og MPNn. Da vi undersøgte markører for inflammation, fandt vi en højere grad af systemisk inflammation i MPNd end MPNn. Dette blev vist ved en højere inflammationsscore (udregnet på baggrund af niveauer af pro-inflammatoriske markører), en højere neutrofil-lymfocyt ratio, samt indikationer på et dereguleret komplementsystem. Ved undersøgelse af aldringsmarkører fandt vi tegn på accelereret immunaldring hos MPNd i forhold til MPNn, hvilket kommer til udtryk ved en større procentdel af "effector memory T celler". Endelig fandt vi en vaesentlig lavere ekspression af CXCR3 på T celler og monocytter hos patienter med nAMD sammenlignet med iAMD, MPNd og MPNn. Dette er i overensstemmelse med tidligere studier hvor CXCR3 ekspression er fundet lavere end hos raske kontroller. Derudover fandt vi en faldende CXCR3 ekspression på monocytter over det biologiske MPN-kontinuum. Disse studier indikerer en involvering af CXCR3 i både nAMD og PMF, begge sygdomsstadier som er karakteriseret ved angiogenese og fibrose. Ud fra resultaterne af denne afhandling kan vi konkludere at forekomsten af druser og AMD hos MPN er øget i forhold til baggrundsbefolkningen. Endvidere viser vores resultater at systemisk inflammation muligvis spiller en vaesentlig større rolle i udviklingen af AMD end tidligere antaget. Vi foreslår derfor en AMD-model (Figur 18) hvor inflammation kan initiere og accelerere den normale aldersafhaengige akkumulation af affaldsstoffer i nethinden, som senere udvikler sig til druser, medførende øget lokal inflammation og med tiden tidlig og intermediaer AMD. Dette resulterer i den øgede risiko for udvikling til de invaliderende senstadier af AMD. ENGLISH SUMMARY: Age-related macular degeneration (AMD) is the most common cause of irreversible vision loss and blindness in high-income countries. It is a progressive retinal disease leading to damage of the cells responsible for central vision. The early stages of the disease are often asymptomatic, while late-stage AMD, which is divided into two entities, neovascular AMD and geographic atrophy (GA), both show vision loss, though generally with different progression rates. Drusen and pigmentary abnormalities in the retina characterise early AMD, while nAMD and GA show angiogenesis in and atrophy of the retina, respectively. The aetiology is multifactorial and, in addition to ageing, which is the most significant risk factor for developing AMD, environmental- and genetic risk factors are implicated in the pathogenesis. Research has focused on local changes in the eye where inflammation has been found to play an essential role, but studies also point to systemic alterations and especially systemic inflammation to be involved in the pathogenesis. The Philadelphia-negative myeloproliferative neoplasms (MPN) are a group of haematological cancers with an acquired genetic defect of the pluripotent haematopoietic stem cell, characterised by excess haematopoiesis of the myeloid cell lineage. The diseases have been found to evolve in a biological continuum from early cancer state, essential thrombocythemia, over polycythaemia vera (PV), to the advanced myelofibrosis stage (PMF). The symptoms in these patients are often a result of the changes in the blood composition, hyperviscosity, microvascular disturbances, and reduced tissue perfusion. The major causes of morbidity and mortality are thromboembolic- and haemorrhagic events, and leukemic transformation. A group of mutations that drive the MPNs has been identified, e.g., the JAK2V617F mutation, which results in deregulation of the JAK/STAT signal transduction pathway important, for instance, in cell differentiation and survival. A previous large register study has shown that patients with MPNs have an increased risk of neovascular AMD, and a pilot study has shown an increased prevalence of intermediate AMD. We wish to study this further in a larger scale study. Several studies have also shown that systemic inflammation plays an essential role in both the initiation and progression of the malignant cell clone in MPNs. From this knowledge, a "Human inflammation model" has been developed. Since then, the MPNs has been used as model diseases for a similar inflammation model for the development of Alzheimer's disease. In this PhD project, we would like to investigate systemic inflammation in relation to drusen presence. We will do this by comparing systemic immunological markers previously investigated in patients with AMD and compare with MPN. We are primarily interested in systemic immunological differences between patients with MPN and drusen (MPNd) and MPN with normal retinas (MPNn). This thesis consists of two main studies. Study I investigated the prevalence of retinal changes associated with AMD and the prevalence of different AMD stages in 200 patients with MPN (paper I). Study II examined immunological similarities between AMD and MPNs. This study was divided into three substudies exploring systemic markers of inflammation, ageing and angiogenesis, respectively. This was done in four types of patients: nAMD, intermediate AMD (iAMD), MPNd and MPNn. Investigating, differences between MPNd and MPNn, will make it possible to identify changes in the immune system, relevant for AMD pathogenesis. Additionally, we will compare patients with MPNs with patients with iAMD and nAMD. In study I (Paper I), we found that patients with MPNs have a significantly higher prevalence of large drusen and consequently AMD from an earlier age compared to the estimates from three large population-based studies. We also found that drusen prevalence was associated with a higher neutrophil-to-lymphocyte ratio indicating a higher level of chronic low-grade inflammation in patients with drusen compared to those without drusen. In study II (papers II, III and IV), we found immunological differences between patients with MPNd and MPNn. When we investigated markers of inflammation, we found a higher level of systemic inflammation in MPNd than MPNn. This was indicated by a higher inflammation score (based on levels of pro-inflammatory markers), a higher neutrophil-to-lymphocyte ratio, and indications of a deregulated complement system. When examining markers of ageing, we found signs of accelerated immune ageing in MPNd compared to MPNn, shown by more senescent effector memory T cells. Finally, when exploring a marker of angiogenesis, we found a lower CXCR3 expression on monocytes and T cells in nAMD compared to iAMD, MPNd and MPNn, in line with previous studies of nAMD compared to healthy controls. Further, we found decreasing CXCR3 expression over the MPN biological continuum. These studies indicate CXCR3 involvement in both nAMD and PMF, two disease stages characterised by angiogenesis and fibrosis. From the results of this PhD project, we can conclude that the prevalence of drusen and AMD is increased in patients with MPN compared to the general population. Further, our results show that systemic inflammation may play a far more essential role in AMD pathogenesis than previously anticipated. We, therefore, propose an AMD model (Figure 18) where inflammation can initiate and accelerate the normal age-dependent accumulation of debris in the retina, which later evolve into drusen, resulting in increased local inflammation, and over time early- and intermediate AMD. This results in the increased risk of developing the late debilitating stages of AMD.

Cellular Senescence and Periodontitis: Mechanisms and Therapeutics

Periodontitis is a chronic inflammatory disease which increases in prevalence and severity in the older population. Aging is a leading risk factor for periodontitis, which exacerbates alveolar bone loss and results in tooth loss in the elderly. However, the mechanism by which aging affects periodontitis is not well understood. There is considerable evidence to suggest that targeting cellular senescence could slow down the fundamental aging process, and thus alleviate a series of age-related pathological conditions, likely including alveolar bone loss. Recently, it has been discovered that the senescent cells accumulate in the alveolar bone and promote a senescence-associated secretory phenotype (SASP). Senescent cells interacting with bacteria, together with secreted SASP components altering the local microenvironment and inducing paracrine effects in neighboring cells, exacerbate the chronic inflammation in periodontal tissue and lead to more alveolar bone loss. This review will probe into mechanisms underlying excessive alveolar bone loss in periodontitis with aging and discuss potential therapeutics for the treatment of alveolar bone loss targeting cellular senescence and the SASP. Inspecting the relationship between cellular senescence and periodontitis will lead to new avenues of research in this field and contribute to developing potential translatable clinical interventions to mitigate or even reverse the harmful effects of aging on oral health.

Effects of physical distancing by COVID-19 pandemic on diet quality, neurological and immunological markers, and fecal microbiota of Brazilian older women

Physical distancing was used to prevent transmission of COVID-19, however there are concerns that this may promote harmful impacts on health, such as reduced levels of physical practice and changes in food intake and gut microbiota composition. This study evaluated the impacts of 6 months physical distancing on Brazilian older women upon body mass index (BMI), strength, physical activity level (IPAQ), eating habits, neurological markers (brain-derived neurotrophic factor-BDNF and cortisol), cytokines (IL-2, IL-5, IL-6, IL-10, interferon-IFN-γ, tumor necrosis factor-TNF-α), aging-associated markers (vascular endothelial growth factor-VEGF, insulin-like growth factor-IGF-1, klotho and thymic stromal lymphopoietin-TSLP), besides specific groups of fecal microbiota. Fifteen women, over 60 years old, residents of São Paulo state (Brazil), were evaluated in March and in September 2020. The older adult women, with a mean age 66 ± 6.2 years presented significantly increased BMI and high effect size for non-protective foods consumption, reduced light physical activity and strength 6 months following the physical distancing. Furthermore, the serum concentration of IFN-γ, IGF-1, and IFN-γ/IL-5 were significantly higher, while lower concentration of IL-2 and IL-5 were observed 6 months after the physical distancing. Significant increase was noted only to Blautia spp. abundance after 6 months of physical distancing. Several correlations were observed at both before and after physical distancing, however, interestingly, many of them were lost or inverted 6 months following, while new ones emerged. Taken together, these results showed that lifestyle changes and stress conditions addressed by physical distancing from the COVID-19 pandemic impacted the health of older women included in the present study. Therefore, future follow-up studies are essential to propose interventions in order to restore the health conditions observed before the pandemic period, and thus to maintain the quality of life of older adults in different socioeconomic contexts.

Nutritional senolytics and senomorphics: Implications to immune cells metabolism and aging – from theory to practice

Aging is a natural physiological process, but one that poses major challenges in an increasingly aging society prone to greater health risks such as diabetes, cardiovascular disease, cancer, frailty, increased susceptibility to infection, and reduced response to vaccine regimens. The loss of capacity for cell regeneration and the surrounding tissue microenvironment itself is conditioned by genetic, metabolic, and even environmental factors, such as nutrition. The senescence of the immune system (immunosenescence) represents a challenge, especially when associated with the presence of age-related chronic inflammation (inflammaging) and affecting the metabolic programming of immune cells (immunometabolism). These aspects are linked to poorer health outcomes and therefore present an opportunity for host-directed interventions aimed at both eliminating senescent cells and curbing the underlying inflammation. Senotherapeutics are a class of drugs and natural products that delay, prevent, or reverse the senescence process – senolytics; or inhibit senescence-associated secretory phenotype – senomorphics. Natural senotherapeutics from food sources – nutritional senotherapeutics – may constitute an interesting way to achieve better age-associated outcomes through personalized nutrition. In this sense, the authors present herein a framework of nutritional senotherapeutics as an intervention targeting immunosenescence and immunometabolism, identifying research gaps in this area, and gathering information on concluded and ongoing clinical trials on this subject. Also, we present future directions and ideation for future clinical possibilities in this field.

2022 AAHA Canine Vaccination Guidelines

These guidelines are an update and extension of previous AAHA peer-reviewed canine vaccination guidelines published in 2017. Vaccination is a cornerstone of canine preventive healthcare and one of the most cost-effective ways of maintaining a dog's health, longevity, and quality of life. Canine vaccination also serves a public health function by forming a barrier against several zoonotic diseases affecting dogs and humans. Canine vaccines are broadly categorized as containing core and noncore immunizing antigens, with administration recommendations based on assessment of individual patient risk factors. The guidelines include a comprehensive table listing canine core and noncore vaccines and a recommended vaccination and revaccination schedule for each vaccine. The guidelines explain the relevance of different vaccine formulations, including those containing modified-live virus, inactivated, and recombinant immunizing agents. Factors that potentially affect vaccine efficacy are addressed, including the patient's prevaccination immune status and vaccine duration of immunity. Because animal shelters are one of the most challenging environments for prevention and control of infectious diseases, the guidelines also provide recommendations for vaccination of dogs presented at or housed in animal shelters, including the appropriate response to an infectious disease outbreak in the shelter setting. The guidelines explain how practitioners can interpret a patient's serological status, including maternally derived antibody titers, as indicators of immune status and suitability for vaccination. Other topics covered include factors associated with postvaccination adverse events, vaccine storage and handling to preserve product efficacy, interpreting product labeling to ensure proper vaccine use, and using client education and healthcare team training to raise awareness of the importance of vaccinations.

Age-associated alterations in immune function and inflammation

Immunosenescence is a term used to describe the age-related changes in the immune system. Immunosenescence is associated with complex alterations and dysregulation of immune function and inflammatory processes. Age-related changes in innate immune responses including alterations in chemotactic, phagocytic, and natural killing functions, impaired antigen presenting capacity, and dysregulated inflammatory response have been described. The most striking and best characterized feature of immunosenescence is the decline in both number and function of T cells. With age there is decreased proliferation, decreased number of antigen-naïve T cells, and increased number of antigen-experienced memory T cells. This decline in naïve T cell population is associated with impaired immunity and reduced response to new or mutated pathogens. While the absolute number of peripheral B cells appears constant with age, changes in B cell functions including reduced antibody production and response and cell memory have been described. However, the main alteration in cell-mediated function that has been reported across all species with aging is those observed in in T cell. These T cell mediated changes have been shown to contribute to increased susceptibility to infection and cancer in older adults. In addition to functional and phenotype alterations in immune cells, studies demonstrate that circulating concentrations of inflammatory mediators in older adults are higher than those of young. This low grade, chronic inflammatory state that occurs in the context of aging has been termed "inflammaging". This review will focus on age-related changes in the immune system including immunosenescence and inflammation as well as the functional consequences of these age-related alterations for the aged.