Changes in immune function with age

3D Mitochondrial Structure in Aging Human Skeletal Muscle: Insights into MFN-2 Mediated Changes

Age-related atrophy of skeletal muscle, is characterized by loss of mass, strength, endurance, and oxidative capacity during aging. Notably, bioenergetics and protein turnover studies have shown that mitochondria mediate this decline in function. Although exercise has been the only therapy to mitigate sarcopenia, the mechanisms that govern how exercise serves to promote healthy muscle aging are unclear. Mitochondrial aging is associated with decreased mitochondrial capacity, so we sought to investigate how aging affects mitochondrial structure and potential age-related regulators. Specifically, the three-dimensional (3D) mitochondrial structure associated with morphological changes in skeletal muscle during aging requires further elucidation. We hypothesized that aging causes structural remodeling of mitochondrial 3D architecture representative of dysfunction, and this effect is mitigated by exercise. We used serial block-face scanning electron microscopy to image human skeletal tissue samples, followed by manual contour tracing using Amira software for 3D reconstruction and subsequent analysis of mitochondria. We then applied a rigorous in vitro and in vivo exercise regimen during aging. Across 5 human cohorts, we correlate differences in magnetic resonance imaging, mitochondria 3D structure, exercise parameters, and plasma immune markers between young (under 50 years) and old (over 50 years) individuals. We found that mitochondria we less spherical and more complex, indicating age-related declines in contact site capacity. Additionally, aged samples showed a larger volume phenotype in both female and male humans, indicating potential mitochondrial swelling. Concomitantly, muscle area, exercise capacity, and mitochondrial dynamic proteins showed age-related losses. Exercise stimulation restored mitofusin 2 (MFN2), one such of these mitochondrial dynamic proteins, which we show is required for the integrity of mitochondrial structure. Furthermore, we show that this pathway is evolutionarily conserved as Marf, the MFN2 ortholog in Drosophila, knockdown alters mitochondrial morphology and leads to the downregulation of genes regulating mitochondrial processes. Our results define age-related structural changes in mitochondria and further suggest that exercise may mitigate age-related structural decline through modulation of mitofusin 2.

Inflammatory processes in the prefrontal cortex induced by systemic immune challenge: Focusing on neurons

Peripheral immune challenge induces neurobiological alterations in the brain and related neuropsychiatric symptoms both in humans and other mammals. One of the best known physiological effects of systemic inflammation is sickness behavior. However, in addition to this depression-like state, there are other cognitive outcomes of peripherally induced neuroinflammation that can be linked to the dysfunction of higher-order cortical areas, such as the prefrontal cortex (PFC). As the physiological activity of the PFC is largely based on the balanced interplay of excitatory pyramidal cells and inhibitory interneurons, it may be hypothesized that neuroinflammatory processes result in a shift of excitatory/inhibitory balance, which is a common hallmark of several neuropsychiatric conditions. Indeed, many data suggest that peripherally induced neuroinflammation is strongly associated with molecular and functional changes in PFC neurons leading to disturbances in their synaptic networks. Different experimental approaches may cause some incongruence in the reviewed data. However, it is commonly agreed that acute systemic inflammation leads to changes in the excitatory/inhibitory balance in the PFC by proinflammatory signaling at the brain borders and in the brain parenchyma. These cellular changes result in altered local and brain-wide network activity inducing disturbances in the top-down control of goal-directed behavior and cognition regulated by the PFC. Lipopolysaccharide (LPS)-treated rodents are the most widely used experimental models of peripherally induced neuroinflammation, so the majority of the reviewed data come from studies utilizing the LPS model. This may limit their general interpretation regarding the neuronal effects of peripheral immune activation. In addition, several biological variables (e.g., sex, age) can influence the PFC effects of systemic immune challenge, not only the nature and severity of immune activation. Therefore, it would be desirable to investigate inflammation-related neuronal changes in the PFC using other models of systemic inflammation as well, and to focus on the targeted fine-tuning of the affected cell types via common molecular mechanisms of the immune and nervous systems.

The effectiveness of influenza vaccine among elderly Chinese: A regression discontinuity design based on Yinzhou regional health information platform

In China, a free influenza vaccination policy is being implemented among individuals aged 70 years and over in Zhejiang province during the COVID-19 pandemic. The objective was to assess the effectiveness of influenza vaccine in reducing hospitalization and mortality in the elderly. We used data from the Regional Health Information Platform in Yinzhou located in Zhejiang province and applied a regression discontinuity design to estimate the intention-to-treat effect on admission and mortality rates by month of age in the population who was near the age of 70 years threshold. At age 70 years, the influenza vaccination rate increased by 29.1% (95% CI, 28.2% to 29.9%) compared to those under 70 in the study population. When turning age 70 years, the potential effectiveness of receiving influenza vaccine was 8.2% (95% CI, -36.8% to 51.3%) for total hospitalization and the evaluation of vaccine effectiveness was 13.1% (95% CI, -34.2 to 61.8) for the all-cause mortality. An increase in the influenza vaccination rate was associated with a weak decline in most outcomes, but no significance was found for all outcomes. Influenza vaccination had a limited effect on hospital admission and mortality for the free influenza vaccination program that can be related to the low vaccination rate among the Chinese elderly. Supplementation strategies and future studies may be needed to expand immunization coverage and validate this finding, and further provide a reference for other cities to promote the free influenza vaccination policy in China, especially under circumstances of the COVID-19 pandemic.

Long-term PM2.5 exposure and sepsis mortality in a US medicare cohort

Background

Risk factors contributing to sepsis-related mortality include clinical conditions such as cardiovascular disease, chronic lung disease, and diabetes, all of which have also been shown to be associated with air pollution exposure. However, the impact of chronic exposure to air pollution on sepsis-related mortality has been little studied. 

Methods

In a cohort of 53 million Medicare beneficiaries (228,439 sepsis-related deaths) living across the conterminous United States between 2000 and 2008, we examined the association of long-term PM_2.5 exposure and sepsis-related mortality. For each Medicare beneficiary (ages 65–120), we estimated the 12-month moving average PM_2.5 concentration for the 12 month before death, for their ZIP code of residence using well validated GIS-based spatio-temporal models. Deaths were categorized as sepsis-related if they have ICD-10 codes for bacterial or other sepsis. We used Cox proportional hazard models to assess the association of long-term PM_2.5 exposure on sepsis-related mortality. Models included strata for age, sex, race, and ZIP code and controlled for neighborhood socio-economic status (SES). We also evaluated confounding through adjustment of neighborhood behavioral covariates.

Results

A 10 μg/m³ increase in 12-month moving average PM_2.5 was associated with a 9.1% increased risk of sepsis mortality (95% CI: 3.6–14.9) in models adjusted for age, sex, race, ZIP code, and SES. HRs for PM_2.5 were higher and statistically significant for older (> 75), Black, and urban beneficiaries. In stratified analyses, null associations were found for younger beneficiaries (65–75), beneficiaries who lived in non-urban ZIP codes, and those residing in low-SES urban ZIP codes.

Conclusions

Long-term PM_2.5 exposure is associated with elevated risks of sepsis-related mortality.

Correlation between nutritional status and oral health quality of life, self-efficacy of older inpatients and the influencing factors

OBJECTIVE

This study explores the relationship between nutritional status and oral health quality of life, the self-efficacy of older inpatients and the correlative factors.

METHODS

In this study, the convenience sampling method was used to select 307 older inpatients in the southern section of the Renji Hospital affiliated to Shanghai Jiao Tong University School of Medicine from October to December 2020 as the main research participants. A mini nutritional assessment questionnaire was used to assess nutritional status, and the Chinese version of a geriatric oral health assessment index questionnaire was used to determine the oral health quality of life. Self-efficacy was assessed by a general self-efficacy scale questionnaire. Descriptive statistics were used to analyse data using the SPSS 22.0 software. Pearson correlation and multiple linear regression analysis were applied to explore the correlation between variables and factors concerned with nutritional status, respectively.

RESULTS

The results of this study showed that the self-efficacy and oral health quality of life of older inpatients were at a moderate level. Among the patients, 263 had one or more tooth defects, and only 128 had oral restorations or wore dentures. The risk of malnutrition in hospitalised older patients was 37.1%, and the incidence of malnutrition was 13.4%. The risk factors of nutritional status of older patients were age, oral-related quality of life, prealbumin index, self-efficacy, chronic disease, monthly income and tooth defect (P < 0.05).

CONCLUSION

The incidence of malnutrition and malnutrition risk in hospitalised older patients is relatively high. The main associated factors include age, tooth defect, oral health quality of life, self-efficacy, chronic disease status and monthly income. Therefore, older inpatients, especially those with prosthodontic problems, should carry out nutritional assessments, intervention and graded management as soon as possible to improve their self-efficacy, improve their nutrition and health status and reduce the incidence of a poor prognosis.

Transmissible cancer influences immune gene expression in an endangered marsupial, the Tasmanian devil (Sarcophilus harrisii)

Understanding the effects of wildlife diseases on populations requires insight into local environmental conditions, host defence mechanisms, host life‐history trade‐offs, pathogen population dynamics, and their interactions. The survival of Tasmanian devils (Sarcophilus harrisii) is challenged by a novel, fitness limiting pathogen, Tasmanian devil facial tumour disease (DFTD), a clonally transmissible, contagious cancer. In order to understand the devils’ capacity to respond to DFTD, it is crucial to gain information on factors influencing the devils’ immune system. By using RT‐qPCR, we investigated how DFTD infection in association with intrinsic (sex and age) and environmental (season) factors influences the expression of 10 immune genes in Tasmanian devil blood. Our study showed that the expression of immune genes (both innate and adaptive) differed across seasons, a pattern that was altered when infected with DFTD. The expression of immunogbulins IgE and IgM:IgG showed downregulation in colder months in DFTD infected animals. We also observed strong positive association between the expression of an innate immune gene, CD16, and DFTD infection. Our results demonstrate that sampling across seasons, age groups and environmental conditions are beneficial when deciphering the complex ecoevolutionary interactions of not only conventional host‐parasite systems, but also of host and diseases with high mortality rates, such as transmissible cancers.

Low COVID-19 impact in Africa: The multifactorial Nexus

Africa has defied predictions of being the worst hit by the novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which has devastated Europe, the Americas, and some Asian countries. However, with a current second and third wave of the COVID-19 pandemic across other continents, pertinent​ questions have arisen regarding the lower disease severity and seemingly better outcomes in most African countries. Several factors have been proposed as discussed in this review including, underreporting, quick lockdown measures, effective public health intervention, younger population structure, cross-immunity and experience from fighting previous epidemics, such as the Ebola virus outbreak, previous infections or vaccinations, genetic predisposition, and tropical climate. We have discussed the implications of these factors on the magnitude of the outbreak and the better-than-expected outcomes observed in Africa. In addition, other potential factors like vitamin-D deficiency and chronic non-communicable diseases could predispose non-African regions to severe COVID-19 outcome. Therefore, this review further advocates for research to understand the precise mechanisms responsible for the pandemic’s relatively mild impact in Africa and proposed recommendations to prevent an infection surge.

Immunosuppression Considerations for Older Kidney Transplant Recipients

PURPOSE OF REVIEW

While kidney transplantation improves the long-term survival of the majority of patients with end-stage kidney disease (ESKD), age-related immune dysfunction and associated comorbidities make older transplant recipients more susceptible to complications related to immunosuppression. In this review, we discuss appropriate management of immunosuppressive agents in older adults to minimize adverse events, avoid acute rejection, and maximize patient and graft survival.

RECENT FINDINGS

Physiological changes associated with senescence can impact drug metabolism and increase the risk of posttransplant infection and malignancy. Clinical trials assessing the safety and efficacy of immunosuppressive agents in older adults are lacking. Recent findings from U.S. transplant registry-based studies suggest that risk-adjusted death-censored graft failure is higher among older patients who received antimetabolite avoidance, mammalian target of rapamycin inhibitor (mTORi)-based, and cyclosporine-based regimens. Observational data suggest that risk-adjusted mortality may be increased in older patients who receive mTORi-based and cyclosporine-based regimens but lower in those managed with T-cell induction and maintenance steroid avoidance/withdrawal.

SUMMARY

Tailored immunosuppression management to improve patient and graft survival in older transplant recipients is an important goal of personalized medicine. Lower intensity immunosuppression, such as steroid-sparing regimens, appear beneficial whereas mTORi- and cyclosporine-based maintenance are associated with greater potential for adverse effects. Prospective clinical trials to assess the safety and efficacy of immunosuppression agents in older recipients are urgently needed.

The Effect of Influenza Vaccination for the Elderly on Hospitalization and Mortality: An Observational Study With a Regression Discontinuity Design

BACKGROUND

Observational studies using traditional research designs suggest that influenza vaccination reduces hospitalizations and mortality among elderly persons. Accordingly, health authorities in some countries prioritize vaccination of this population. Nevertheless, questions remain about this policy's effectiveness given the potential for bias and confounding in observational data.

OBJECTIVE

To determine the effectiveness of the influenza vaccine in reducing hospitalizations and mortality among elderly persons by using an observational research design that reduces the possibility of bias and confounding.

DESIGN

A regression discontinuity design was applied to the sharp change in vaccination rate at age 65 years that resulted from an age-based vaccination policy in the United Kingdom. In this design, comparisons were limited to individuals who were near the age-65 threshold and were thus plausibly similar along most dimensions except vaccination rate.

SETTING

England and Wales.

PARTICIPANTS

Adults aged 55 to 75 years residing in the study area during 2000 to 2014.

INTERVENTION

Seasonal influenza vaccine.

MEASUREMENTS

Hospitalization and mortality rates by month of age.

RESULTS

The data included 170 million episodes of care and 7.6 million deaths. Turning 65 was associated with a statistically and clinically significant increase in rate of seasonal influenza vaccination. However, no evidence indicated that vaccination reduced hospitalizations or mortality among elderly persons. The estimates were precise enough to rule out results from many previous studies.

LIMITATION

The study relied on observational data, and its focus was limited to individuals near age 65 years.

CONCLUSION

Current vaccination strategies prioritizing elderly persons may be less effective than believed at reducing serious morbidity and mortality in this population, which suggests that supplementary strategies may be necessary.

PRIMARY FUNDING SOURCE

National Institute on Aging.

Novel Cancer Therapeutics in Geriatrics: What is Unique to the Aging Patient?

With the worldwide trend of aging populations, the number of older adults who develop and survive cancer is likely to increase. In the last decade, oncology drug development has shifted away from conventional chemotherapeutics towards agents that can 'target' a driver mutation of a specific cancer or 'unleash' the patient's native immune system to attack the cancer-so-called molecularly targeted therapies and immunotherapeutics. The basic algorithms of cancer treatment in elderly patients are essentially the same as in younger patients; however, one needs to pay exceptional attention to the effects of co-morbidities, interaction with other drugs, and the organ function reserve of an older individual before determining his/her 'eligibility' for a specific cancer treatment modality. Despite the growing evidence of safety and effectiveness of combination chemotherapy in fit elderly patients, the data are still lacking concerning the use of currently approved targeted agents and immunotherapies. The current evidence, though limited, suggests reasonable tolerability with comparable efficacy in patients > 65 years old treated with immune-based therapies to that in younger controls; however, it is unclear if this leads to significant patient-relevant gains such as improved survival with an acceptable quality of life. Nonetheless, these newer agents remain better tolerated than cytotoxic chemotherapy in clinical practice, particularly in older patients. Alternatively, a personalized approach for elderly patients with consideration of the incidence and management of adverse effects, as well as strategies for optimizing efficacy in the context of an aging immune system, would be of utmost value in our aging cancer population. Future trials should also explore immune markers to predict response to these therapeutics in elderly patients, taking into consideration the effects of immunosenescence and immune modulation in aging hosts.

Aging and the immune response to organ transplantation

An increasing number of older people receive organ transplants for various end-stage conditions. Although organ transplantation is an effective therapy for older patients (i.e., older than 65 years of age), such as in end-stage renal disease, this therapy has not been optimized for older patients because of our lack of understanding of the effect of aging and the immune response to organ transplantation. Here, we provide an overview of the impact of aging on both the allograft and the recipient and its effect on the immune response to organ transplantation. We describe what has been determined to date, discuss existing gaps in our knowledge, and make suggestions on necessary future studies to optimize organ transplantation for older people.

Tuberculosis in haemodialysis patients: A single centre experience

We prospectively followed-up new patients of tuberculosis while on maintenance hemodialysis at a State Government-run tertiary care institute. Between 2000 and 2010, 1237 new patients were initiated on maintainence hemodialysis. The number of patients diagnosed with tuberculosis after initiation of hemodialysis was 131 (10.5% of 1237). The age was 46.4 ± 10.4 (range 8-85) years and there were 90 (68.7%) males. The number of patients diagnosed with tuberculosis on the basis of organ involvement were: Pulmonary-60, pleural effusion-31, lymph node-21, meningitis-8, pericardial effusion-7, peritoneum-2, latent tuberculosis-2. The incidence of tuberculosis in hemodialysis was found to be 105.9 per 1000 patient years. Male gender, diabetes mellitus, past history of tuberculosis, mining as an occupation, low serum albumin, and duration of hemodialysis more than 24 months, and unemployment were found to be significant risk-factors on univariate analysis.

Kidney transplantation and the ageing immune system

The world population is rapidly growing and ageing at a pace that is projected to continue for at least three decades. This shift towards an older populace has invariably increased the number of individuals with diseases related to ageing, such as chronic kidney disease. The increase in chronic kidney disease is associated with a growing number of elderly patients receiving kidney transplants. Understanding how the immune system changes with increasing age will help to define the risks of rejection and infection in the elderly population and will focus attention on the need for individualized immunosuppression for patients in this age group. This Review addresses what is currently known about ageing and the immune system, highlighting age-related changes that affect the outcome of transplantation in elderly individuals. The need for new strategies to improve outcomes in this growing population of elderly renal transplant recipients is also emphasized.

Discontinuation of anti-TNF-α therapy in a Chinese cohort of patients with rheumatoid arthritis

The aim of this retrospective study was to examine the predictors of discontinuation of anti-tumor necrosis factor (TNF) therapy due to adverse events in Chinese patients with rheumatoid arthritis (RA). Anti-TNF-related adverse events were recorded and analyzed in 217 consecutive patients with RA followed in our institution from 2003 to 2010. Time to discontinuation of anti-TNF-α therapy was estimated using survival analysis techniques. The anti-TNF agents administered were etanercept in 181 patients and adalimumab in 36 patients. The mean age at diagnosis was 45.2 ± 13.5 years, and mean age at initiation of anti-TNF therapy was 51.8 ± 13.0 years. The mean duration of anti-TNF agent use was 36.0 ± 26.5 months (range, 1.4-87.0; median, 26.4 months). Of the 217 patients, 39 (18.0 %) developed adverse events [etanercept in 34 (18.8 %] and adalimumab in 5 (13.9 %)] during the treatment period (tuberculosis in 5, bacterial infections in 19, virus infection in 7, neuropathy in 3, malignancy in 3, other drug-related events in 1, and appendicitis in 1). In patients with RA, older age (≥55 years) at initiation of anti-TNF therapy [odds ratio (OR), 3.20; 95 % confidence interval (CI), 1.67-6.20; p < 0.001], Cr ≥1.5 mg/dL (OR, 5.72; 95 % CI, 1.17-27.90; p = 0.031), and occurrence of adverse events (OR, 3.82; 95 % CI, 1.75-8.35; p = 0.001) were associated with increased likelihood of discontinuation of anti-TNF treatment. In the present study, a significant proportion (7.8 %, 17/217) of patients with RA discontinued anti-TNF treatment because of adverse events. In the elderly and in patients with renal insufficiency, caution is needed when starting anti-TNF treatment.

Physical activity and influenza-coded outpatient visits, a population-based cohort study

BACKGROUND

Although the benefits of physical activity in preventing chronic medical conditions are well established, its impacts on infectious diseases, and seasonal influenza in particular, are less clearly defined. We examined the association between physical activity and influenza-coded outpatient visits, as a proxy for influenza infection.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a cohort study of Ontario respondents to Statistics Canada's population health surveys over 12 influenza seasons. We assessed physical activity levels through survey responses, and influenza-coded physician office and emergency department visits through physician billing claims. We used logistic regression to estimate the risk of influenza-coded outpatient visits during influenza seasons. The cohort comprised 114,364 survey respondents who contributed 357,466 person-influenza seasons of observation. Compared to inactive individuals, moderately active (OR 0.83; 95% CI 0.74-0.94) and active (OR 0.87; 95% CI 0.77-0.98) individuals were less likely to experience an influenza-coded visit. Stratifying by age, the protective effect of physical activity remained significant for individuals <65 years (active OR 0.86; 95% CI 0.75-0.98, moderately active: OR 0.85; 95% CI 0.74-0.97) but not for individuals ≥ 65 years. The main limitations of this study were the use of influenza-coded outpatient visits rather than laboratory-confirmed influenza as the outcome measure, the reliance on self-report for assessing physical activity and various covariates, and the observational study design.

CONCLUSION/SIGNIFICANCE

Moderate to high amounts of physical activity may be associated with reduced risk of influenza for individuals <65 years. Future research should use laboratory-confirmed influenza outcomes to confirm the association between physical activity and influenza.

T-cell biology in aging, with a focus on lung disease

T cells are essential for defending hosts against microorganisms and malignancy as well as for regulating the development of immune-mediated inflammatory diseases like autoimmunity. Alterations in T-cell immunity occur with aging, affecting the function and proportions of T-cell subsets. Probably, the most noticeable age-associated change in T-cell immunity is an alteration in the frequency of naive and memory CD4+ and CD8+ T cells. In fact, the frequency of naive CD4+ and CD8+ T cells decreases with aging, whereas the frequency of memory CD4+ and CD8+ T cells increases. Also, changes in T-cell proliferation, cytokine production, memory response, and cytotoxicity as well as in regulatory T-cell number and function have been reported with aging. Such alterations could contribute to the development of infections, malignancies, and inflammatory diseases that rise with aging. Of interest, T cells are closely involved in the development of inflammatory airway and lung diseases including asthma and chronic obstructive pulmonary disease, which are prevalent in the elderly people. In addition, T cells play a major role in defending host against influenza virus infection, a serious medical problem with high morbidity and mortality in the elderly people. Thus, it is conceivable that altered T-cell immunity may account in part for the development of such respiratory problems with aging. Here, we will review the recent advances in T-cell immunity and its alteration with aging and discuss the potential effects of such changes on the lung.

An age-specific CD8+ T cell pathway that impairs the effectiveness of strategies to prolong allograft survival

Age-related decline in immunity can impair cell-mediated responses during an infection, malignancy, and acute allograft rejection. Although much research has been allocated to understand the immune responses that impact the former two conditions, the cellular mechanisms by which aging impacts the immune acceptance of organ allografts are not completely clear. In this study, we examined how recipient age impacts the efficacy of therapies that modulate immune recognition of allografts using an immunogenic murine skin transplant model. We found that costimulatory blockade-based treatment failed to extend allograft survival in older recipients to the same extent as that observed in younger recipients. CD8(+) T cells were critical for the inability of aged recipients to achieve maximal allograft survival. Although aged mice displayed a larger number of effector memory T cells prior to transplantation, these cells did not exhibit enhanced alloreactivity compared with young memory T cells. In contrast, naive aged CD8(+) T cells exhibited enhanced IFN-γ production to allostimulation compared with young naive T cells. Our results provide evidence that aging enhances CD8(+) T cell alloreactivity. This could impair the ability of costimulatory blockade-based therapies to prolong allograft survival. Thus, targeting CD8(+) T cells in humans may be a way to improve outcomes in older patients requiring immune modulatory therapy.

Mitochondrial Dysfunction and Oxidative Stress in Asthma: Implications for Mitochondria-Targeted Antioxidant Therapeutics

Asthma is a complex, inflammatory disorder characterized by airflow obstruction of variable degrees, bronchial hyper-responsiveness, and airway inflammation. Asthma is caused by environmental factors and a combination of genetic and environmental stimuli. Genetic studies have revealed that multiple loci are involved in the etiology of asthma. Recent cellular, molecular, and animal-model studies have revealed several cellular events that are involved in the progression of asthma, including: increased Th2 cytokines leading to the recruitment of inflammatory cells to the airway, and an increase in the production of reactive oxygen species and mitochondrial dysfunction in the activated inflammatory cells, leading to tissue injury in the bronchial epithelium. Further, aging and animal model studies have revealed that mitochondrial dysfunction and oxidative stress are involved and play a large role in asthma. Recent studies using experimental allergic asthmatic mouse models and peripheral cells and tissues from asthmatic humans have revealed antioxidants as promising treatments for people with asthma. This article summarizes the latest research findings on the involvement of inflammatory changes, and mitochondrial dysfunction/oxidative stress in the development and progression of asthma. This article also addresses the relationship between aging and age-related immunity in triggering asthma, the antioxidant therapeutic strategies in treating people with asthma.

Recipient-based approach to tailoring immunosuppression in liver transplantation

Improvements in the field of transplant immunosuppression (IS) have led to significant advances in long-term survival of liver transplant recipients. Despite this progress, survival rates vary depending on recipient, donor and/or perioperative factors. Tailoring IS based on recipient factors is of growing interest among health care providers involved in the care of organ transplant recipients. To date there is no consensus document addressing individualized IS therapy for liver transplant recipients. This review will discuss the information available on the effect of the various IS drugs on recipient-based factors such as age, ethnicity, and liver disease etiology.

A novel adjuvant for vaccine development in the aged

A conformationally-biased, response-selective agonist of human C5a(65-74) (EP67) activated antigen presenting cells (APC) from aged C57Bl/6 mice in vitro and the generation of antigen (Ag)-specific antibody (Ab) responses in aged mice in vivo. EP67, induced the release of the pro-inflammatory cytokines IL-6, TNFα, and INFγ from splenic APCs obtained from both aged and young mice. Both aged and young mice produced high Ag-specific IgG Ab titers when immunized with EP67-containing vaccines to ovalbumin (OVA-EP67) and to a protein (rPrp1) from the cell wall of Coccidioides (rPrp1-EP67). Immunization with EP67-containing vaccines resulted in higher IgG titers in both young and aged mice compared to mice immunized with OVA adsorbed to alum (OVA/alum) and Prp1 admixed with CpG (rPrp1 +CpG). Aged and young mice immunized with the EP67-containing vaccines generated higher titers of IgG1 and IgG2b relative to their aged-matched counterparts immunized with OVA/alum or Prp1 +CpG. These results indicate that EP67 induces humoral immunity in aged mice not obtainable with alum and CpG. These results support the use of EP67 as a potential vaccine adjuvant suited to the elderly.

The causes of acute Fever requiring hospitalization in geriatric patients: comparison of infectious and noninfectious etiology

Introduction. Infectious diseases may present with atypical presentations in the geriatric patients. While fever is an important finding of infections, it may also be a sign of noninfectious etiology. Methods. Geriatric patients who were hospitalized for acute fever in our infectious diseases unit were included. Acute fever was defined as presentation within the first week of fever above 37.3°C. Results. 185 patients were included (82 males and 103 females). Mean age was 69.7 ± 7.5 years. The cause of fever was an infectious disease in 135 and noninfectious disease in 32 and unknown in 18 of the patients. The most common infectious etiologies were respiratory tract infections (n = 46), urinary tract infections (n = 26), and skin and soft tissue infections (n = 23). Noninfectious causes of fever were rheumatic diseases (n = 8), solid tumors (n = 7), hematological diseases (n = 10), and vasculitis (n = 7). A noninfectious cause of fever was present in one patient with no underlying diseases and in 31 of 130 patients with underlying diseases. Conclusion. Geriatric patients with no underlying diseases generally had infectious causes of fever while noninfectious causes were responsible from fever in an important proportion of patients with underlying diseases.

Efficacy and safety of anti-tumour necrosis factor in elderly patients with rheumatoid arthritis: an observational study

This study aims to compare the efficacy and safety of anti-TNF agents in elderly (aged >or=65 years) and younger patients (aged 18-65 years) with active RA. The study involved 1,114 RA patients treated with anti-TNF drugs and followed-up for >6 months by LORHEN group, who were divided into two cohorts on the basis of their age (311 aged >or=65 and 803 aged <65 years) in order to evaluate 3-year outcomes and treatment discontinuations. Drug effectiveness was assessed by disease activity (DAS28 and EULAR response), functional status (HAQ) and serological parameters (ESR) at baseline and during anti-TNFalpha therapy; safety was evaluated on the basis of drug discontinuation rates. At baseline, the elderly patients showed greater disease activity (DAS28, ESR) and loss of joint function (HAQ, functional class; p < 0.05). During therapy, clinical and laboratory parameters (DAS28, ESR) improved in both groups without any statistically significant difference between them, whereas the difference in HAQ remained after 36 months of treatment (p < 0.05). Anti-TNFalpha therapy was discontinued by 123 of the elderly (42%) and 282 of the younger patients (36.6%) because of loss of efficacy (17.4% vs. 16.7%), severe adverse events (21.8% vs. 16.9%) or other reasons (2.7% vs. 3%). The number of adverse events was significantly higher in the elderly patients (p < 0.05). Anti-TNFalpha treatment reduced disease activity and led to functional improvement in both groups, although the baseline difference in HAQ remained statistically significant at the end of the follow-up. The elderly patients experienced more infective events.

Tumour necrosis factor-alpha antagonists in the management of rheumatoid arthritis in the elderly: a review of their efficacy and safety

Rheumatoid arthritis (RA) is a chronic inflammatory disease that frequently affects people aged >or=65 years, causing significant impairment with pain and functional disability. Elderly RA patients have specific problems, including co-morbid diseases, numerous concomitant medications, greater number of damaged joints as a result of longer disease duration and often a more severe disease presentation in elderly-onset RA. These factors, together with an age-related decline in the immune defence mechanisms, make elderly patients more vulnerable. The new era of biologic medications has made intensive treatment of RA patients possible. Anti-tumour necrosis factor-alpha (anti-TNFalpha) agents can cause a dramatic improvement in disease activity and functional capacity, making complete remission of RA a possible target. TNFalpha has been shown to play an important role in both the healthy aging process and age-related diseases such as RA. Targeting this cytokine in elderly patients is therefore reasonable. However, it is not clear whether treatment effects can be reached to the same extent in both elderly and younger patients and whether anti-TNFalpha treatment specifically increases the risk of certain adverse events in elderly RA patients. This review discusses the currently available evidence relating to the efficacy and safety of anti-TNFalpha medication in RA patients aged >or=65 years treated in clinical trials and observational studies. Despite a slightly less robust effect in elderly patients, anti-TNFalpha treatment has a similar long-term efficacy in patients aged >or=65 years and patients aged <65 years. The majority of the study results showed that anti-TNFalpha treatment does not elevate the risk of infections beyond the risk found in age-matched controls. When a moderate increase in risk was found, this occurred equally in elderly and younger patients. Furthermore, whereas anti-TNFalpha agents were found to be relatively safe in the treatment of elderly RA patients, treatment with corticosteroids significantly elevated the risk of serious infections. Corticosteroids are frequently used in elderly patients, but the evidence suggests that preference should increasingly be given to anti-TNFalpha agents, for which the expected benefits will mostly outweigh the modestly increased risks of associated adverse events.

New generation pharmacotherapy in elderly multiple myeloma patients

BACKGROUND

Observational databases have demonstrated that the overall prognosis of multiple myeloma patients has markedly improved over the past decade, yet the greatest strides have been attained in younger rather than older patients.

OBJECTIVE

To review recent clinical trials that include new generation agents (thalidomide, lenalidomide and bortezomib) and autologous stem cell transplantation in older multiple myeloma patients.

RESULTS

Conventional regimens such as melphalan plus prednisone can be improved with the addition of thalidomide or bortezomib: more patients attain complete and near-complete remission, and progression-free survival rates are nearly doubled. In addition, autologous hematopoietic stem cell transplantation studies show that this treatment approach can be used successfully in selected older myeloma patients in whom the toxicity profile of autotransplant and resulting overall survival may be similar to that obtained in the younger patient group.

CONCLUSIONS

In the advanced-age population, implementation of new therapies results in significant benefits in older as well as younger patients.

OX40-enhanced tumor rejection and effector T cell differentiation decreases with age

OX40 agonists have potent immunotherapeutic effects against a variety of murine tumors, yet it is unclear the role that age-related immune senescence plays on their efficacy. We found that middle-aged and elderly tumor-bearing mice (12 and 20 mo old, respectively) treated with anti-OX40 were less responsive compared with young mice 6 mo or less of age. Decreased tumor-free survival was observed in both male and female mice, and was not due to changes in the surface expression of OX40 on T cells in older animals. Enumeration of cytokine-producing effector T cells in tumor-bearing mice revealed a significant decline in these cells in the older mice treated with anti-OX40 compared with their younger counterparts. The decrease of this critical T cell population in middle-aged mice was not a result of inherent T cell deficiencies, but was revealed to be T cell extrinsic. Finally, combining IL-12, an innate cytokine, with anti-OX40 boosted levels of differentiated effector T cells in the older anti-OX40-treated mice and partially restored the defective antitumor responses in the middle-aged mice. Our data show that the anti-OX40-enhancement of tumor immunity and effector T cell numbers is decreased in middle-aged mice and was partially reversed by coadministration of the proinflammatory cytokine IL-12.

Aging augments IL-17 T-cell alloimmune responses

As increasing numbers of elderly patients require solid organ transplantation, the need to better understand how aging modifies alloimmune responses increases. Here, we examined whether aged mice exhibit augmented, donor-specific memory responses prior to transplantation. We found that elevated donor-specific IL-17, but not IFN-gamma, responses were observed in aged mice compared to young mice prior to transplantation. Further characterization of the heightened IL-17 alloimmune response with aging demonstrated that memory CD4(+) T cells were required. Reduced IL-2 alloimmune responses with age contributed to the elevated IL-17 phenotype in vitro, and treatment with an anti-IL-17 antibody delayed the onset of acute allograft rejection. In conclusion, aging leads to augmented, donor-specific IL-17 immune responses that are important for the timing of acute allograft rejection in aged recipients. IL-17 targeting therapies may be useful for averting transplant rejection responses in older transplant recipients.

Aging impairs recipient T cell intrinsic and extrinsic factors in response to transplantation

Background

As increasing numbers of older people are listed for solid organ transplantation, there is an urgent need to better understand how aging modifies alloimmune responses. Here, we investigated whether aging impairs the ability of donor dendritic cells or recipient immunity to prime alloimmune responses to organ transplantation.

Principal Findings

Using murine experimental models, we found that aging impaired the host environment to expand and activate antigen specific CD8⁺ T cells. Additionally, aging impaired the ability of polyclonal T cells to induce acute allograft rejection. However, the alloimmune priming capability of donor dendritic cells was preserved with aging.

Conclusion

Aging impairs recipient responses, both T cell intrinsic and extrinsic, in response to organ transplantation.

Aging impairs IFN regulatory factor 7 up-regulation in plasmacytoid dendritic cells during TLR9 activation

Plasmacytoid dendritic cells (pDCs) are innate sensors that produce IFN-alpha in response to viral infections. Determining how aging alters the cellular and molecular function of these cells may provide an explanation of increased susceptibility of older people to viral infections. Hence, we examined whether aging critically impairs pDC function during infection with HSV-2, a viral pathogen that activates TLR9. We found that impaired IFN-alpha production by aged murine pDCs led to impaired viral clearance with aging. Upon TLR9 activation, aged pDCs displayed defective up-regulation of IFN-regulatory factor 7, a key adaptor in the type I IFN pathway, as compared with younger counterparts. Aged pDCs had more oxidative stress, and reducing oxidative stress in aged pDCs partly recovered the age-induced IFN-alpha defect during TLR9 activation. In sum, aging impairs the type I IFN pathway in pDCs, and this alteration may contribute to the increased susceptibility of older people to certain viral infections.

Impaired dendritic cell function in aging leads to defective antitumor immunity

We recently reported that bone marrow-derived dendritic cells (DC) from aged miced are less effective than their young counterparts in inducing the regression of B16-ovalbumin (OVA) melanomas. To examine the underlying mechanisms, we investigated the effect of aging on DC tumor antigen presentation and migration. Although aging does not affect the ability of DCs to present OVA peptide((257-264)), DCs from aged mice are less efficient than those from young mice in stimulating OVA-specific T cells in vitro. Phenotypic analysis revealed a selective decrease in DC-specific/intracellular adhesion molecule type-3-grabbing nonintegrin (DC-SIGN) level in aged DCs. Adoptive transfer experiments showed defective in vivo DC trafficking in aging. This correlates with impaired in vitro migration and defective CCR7 signaling in response to CCL21 in aged DCs. Interestingly, vaccination of young mice using old OVA peptide((257-264))-pulsed DCs (OVA PP-DC) resulted in impaired activation of OVA-specific CD8(+) T cells in vivo. Effector functions of these T cells, as determined by IFN-gamma production and cytotoxic activity, were similar to those obtained from mice vaccinated with young OVA PP-DCs. A decreased influx of intratumor CD8(+) T cells was also observed. Importantly, although defective in vivo migration could be restored by increasing the number of old DCs injected, the aging defect in DC tumor surveillance and OVA-specific CD8(+) T-cell induction remained. Taken together, our findings suggest that defective T-cell stimulation contributes to the observed impaired DC tumor immunotherapeutic response in aging.

Cell autonomous expression of inflammatory genes in biologically aged fibroblasts associated with elevated NF-kappaB activity

BACKGROUND

Chronic inflammation is a well-known corollary of the aging process and is believed to significantly contribute to morbidity and mortality of many age-associated chronic diseases. However, the mechanisms that cause age-associated inflammatory changes are not well understood. Particularly, the contribution of cell stress responses to age-associated inflammation in 'non-inflammatory' cells remains poorly defined. The present cross-sectional study focused on differences in molecular signatures indicative of inflammatory states associated with biological aging of human fibroblasts from donors aged 22 to 92 years.

RESULTS

Gene expression profiling revealed elevated steady-state transcript levels consistent with a chronic inflammatory state in fibroblast cell-strains obtained from older donors. We also observed enhanced NF-kappaB DNA binding activity in a subset of strains, and the NF-kappaB profile correlated with mRNA expression levels characteristic of inflammatory processes, which include transcripts coding for cytokines, chemokines, components of the complement cascade and MHC molecules. This intrinsic low-grade inflammatory state, as it relates to aging, occurs in cultured cells irrespective of the presence of other cell types or the in vivo context.

CONCLUSION

Our results are consistent with the view that constitutive activation of inflammatory pathways is a phenomenon prevalent in aged fibroblasts. It is possibly part of a cellular survival process in response to compromised mitochondrial function. Importantly, the inflammatory gene expression signature described here is cell autonomous, i.e. occurs in the absence of prototypical immune or pro-inflammatory cells, growth factors, or other inflammatory mediators.

Acute bacterial meningitis

Despite advances in medical care including antibiotics and vaccines, meningitis still has a high morbidity and mortality rate, especially in certain high-risk patients. Early diagnosis with the administration of appropriate antibiotics remains the key element of management. This article highlights methods of diagnosis, differential diagnoses, treatment options, and complications of treating bacterial meningitis.

Epigenetics, aging, and autoimmunity

Immune senescence is associated with a decline in T- and B-cell immune responses. It is, therefore, perhaps surprising that aging is linked to the appearance of serological and clinical autoimmunity. Here we review the mechanisms that contribute to the increase in inflammatory and autoimmune responses in aging. The bulk of this review will focus on aging-associated changes in epigenetic mechanisms, and in particular DNA methylation, as this has emerged as an attractive mechanistic link between aging and autoimmunity.

The effect of aging and caloric restriction on murine CD8+ T cell chemokine receptor gene expression

Background

The mechanism explaining the increased disease susceptibility in aging is not well understood. CD8+ T cells are crucial in anti-viral and anti-tumor responses. Although the chemokine system plays a critical role in CD8+ T cell function, very little is known about the relationship between aging and the T cell chemokine system.

Results

In this study we have examined the effect of aging on murine CD8+ T cell chemokine receptor gene expression. Freshly isolated splenic CD8+ T cells from old C57BL/6 mice were found to have higher CCR1, CCR2, CCR4, CCR5 and CXCR5, and lower CCR7 gene expression compared to their younger cohort. Anti-CD3/anti-CD28 stimulation elicited a similar robust chemokine receptor response from young and old CD8+ T cells. Western blot analyses confirmed elevated protein level of CCR4 and CCR5 in aged CD8+ T cells. Increases in T cell CCR1 and CCR5 expression also correlate to increased in vitro chemotaxis response to macrophage-inflammatory protein-1 α(MIP-1α). Finally, caloric restriction selectively prevents the loss of CD8+ T cell CCR7 gene expression in aging to the level that is seen in young CD8+ T cells.

Conclusion

These findings are consistent with the notion that aging exists in a state of low grade pro-inflammatory environment. In addition, our results provide a potential mechanism for the reported aging-associated impaired T cell lymphoid homing and allograft response, and reduced survival in sepsis.

A case of very-late-onset systemic lupus erythematosus

A 93-year-old woman was admitted to our hospital because of fever. Radiographic findings revealed accumulation of pleural fluid. Moreover, blood tests revealed inflammation, lymphopenia, hypocomplementemia, positive for anti-nuclear antibody, and elevated anti-DNA antibody level. Therefore, the patient was diagnosed with pleuritis associated with systemic lupus erythematosus (SLE). Administration of prednisolone 20 mg/day resulted in a marked improvement in fever, pleuritis, and laboratory findings. We report a case of very-late-onset SLE that occurred at the age of 93.

Tolerance and effectiveness of anti–tumor necrosis factor α therapies in elderly patients with rheumatoid arthritis: A population-based cohort study

OBJECTIVE

Limited data have been published on tolerance to and efficacy of classic or biologic disease-modifying antirheumatic drugs in elderly patients with rheumatoid arthritis (RA). The goal of the present study was to evaluate the tolerance to and effectiveness of anti-tumor necrosis factor (anti-TNF) agents in elderly patients (> or =65 years old) with RA (ERA) in comparison with younger patients (YRA).

METHODS

The Swiss Clinical Quality Management program for RA is a longitudinal population-based cohort. All patients who had received at least 1 dose of anti-TNF agents between January 1997 and November 2005 were included and categorized according to their age. Tolerance was assessed by analyzing discontinuation rates of anti-TNF agents. Effectiveness of these agents was assessed by analyzing RA disease activity (Disease Activity Score in 28 joints [DAS28]) and functional disability (Health Assessment Questionnaire [HAQ]) after anti-TNF initiation.

RESULTS

Among 1,571 patients with RA treated with anti-TNF agents, 344 were > or =65 years of age at treatment initiation. Drug discontinuation rates (median time 3 years) and mean change in DAS28 scores at 2 years (-0.65 versus -0.58) were identical in ERA and YRA. However, HAQ score improved significantly less in ERA (-0.02) than in YRA (-0.1) and a subsequent analysis revealed that this finding was essentially due to patients >75 years of age.

CONCLUSION

Age in itself should not interfere with the decision to treat elderly patients with RA with anti-TNF agents. In a subset of patients ages >75 years, no functional improvement according to HAQ should be expected despite improvements in disease activity.

Effect of aging on bone marrow-derived murine CD11c+CD4-CD8alpha- dendritic cell function

Dendritic cells (DCs) are actively used as cellular adjuvant in cancer immunotherapy. However, although DC immunotherapies primarily target the elderly population, little is known about the effect of aging on DC functions. Here, we compared the T-cell stimulation, cytokine production, and tumor surveillance functions of bone marrow-derived CD11c(+)CD4(-)CD8alpha(-) DCs of old and young C57BL/6 mice. Old immature bone marrow-derived CD4(-)CD8alpha(-) DCs (imDCs) were 4 times less effective than were young DCs in stimulating syngeneic CD4(+) T-cell proliferation. Old imDCs also have decreased DC-specific/intracellular adhesion molecule type 3-grabbing, nonintegrin (DC-SIGN) expression compared to young DCs. Interestingly, mice treated with the ovalbumin peptide-pulsed young DCs exhibited significantly greater tumor regression than with ovalbumin peptide-pulsed old DCs. Old terminally differentiated bone marrow-derived DCs (tDC) also have increased interleukin-10, but decreased interleukin-6 and tumor necrosis factor-alpha production. Taken together, these results have important implications in the clinical application of DC-based tumor immunotherapy in elderly persons.

Murine [corrected] myeloid dendritic cell-dependent toll-like receptor immunity is preserved with aging

The immune response is the result of the interplay between innate and adaptive immunity, yet the impact of aging on this interaction is unclear. Addressing this fundamental question will be critical for the development of effective vaccines for the rapidly rising older subpopulation that manifests increased prevalence of malignancies and infections. Therefore, we undertook the current study to investigate whether aging impairs toll-like receptor (TLR) function in myeloid dendritic cells and whether this leads to reduced T-cell priming. Our results demonstrate that innate TLR immune priming function of myeloid bone marrow derived and splenic dendritic cells (DC) is preserved with aging using both allogeneic and infectious murine experimental systems. In contrast, aging impairs in vitro and in vivo intrinsic T-cell function. Therefore, our results demonstrate that myeloid DCs manifest preserved TLR-mediated immune responses with aging. However, aging critically impairs intrinsic adaptive T-cell function.

Changes in immune responses to oxidized LDL epitopes during aging in hypercholesterolemic apoE(−/−) mice

Atherosclerosis is a disease associated with aging and is subject to modulation by both the innate and adaptive immune system. The time course of age-dependent changes in immune regulation in the context of atherosclerosis has not been characterized. This study aims to describe alteration of the immune responses to oxidized LDL (oxLDL) during aging that is associated with changes in plaque size and phenotype in apoE(−/−) mice. Mice fed a Western diet were euthanized at 15–17, 36, or >52 wk of age. The descending aortas were stained for assessment of extent of atherosclerosis. Plaque lipid, macrophage, and collagen content were evaluated in aortic sinus lesions. The adaptive immune response to oxLDL was assessed using anti-malondialdehyde-oxidized LDL (MDA-LDL) and copper-oxidized LDL (Cu-oxLDL) IgG, and the innate immune response was assessed using anti-Cu-oxLDL and phosphorylcholine (PC) IgM. Aging was associated with a significant increase in plaque area and collagen content and a decrease in plaque macrophage and lipid content. MDA-LDL IgG significantly increased at 36 wk but was reduced in mice >52 wk. Cu-oxLDL IgG increased with age and IgG-apoB immune complexes were increased in the >52 wk group. Cu-oxLDL and PC IgM significantly increased with age. The expression of splenic cytokines such as IFN-γ, IL-4, and IL-10 increased with age. Our study shows a generalized increase in innate immune responses associated with progression of atherosclerosis and a less inflammatory and less lipid-containing plaque phenotype during aging. The adaptive immune response appeared to be less generalized, with a specific reduction in MDA-LDL IgG.

Infectious Emergencies in the Elderly

As life expectancy continues to rise, the number of geriatric patients will increase and the percentages of geriatric patients seen in the emergency department will reflect those numbers. Emergency physicians are responsible for making immediate diagnoses and initiating expeditious treatment. Infectious diseases in the elderly are more prevalent, challenging to diagnose, and are associated with greater morbidity and mortality than with the younger patient population.

Pharmacokinetic Considerations Relating to Tacrolimus Dosing in the Elderly

Relaxation of the upper age limits for solid organ transplantation coupled with improvements in post-transplant survival have resulted in greater numbers of elderly patients receiving immunosuppressant drugs such as tacrolimus. Tacrolimus is a potent agent with a narrow therapeutic window and large inter- and intraindividual pharmacokinetic variability. Numerous physiological changes occur with aging that could potentially affect the pharmacokinetics of tacrolimus and, hence, patient dosage requirements. Tacrolimus is primarily metabolised by cytochrome P450 (CYP) 3A enzymes in the gut wall and liver. It is also a substrate for P-glycoprotein, which counter-transports diffused tacrolimus out of intestinal cells and back into the gut lumen. Age-associated alterations in CYP 3A and P-glycoprotein expression and/or activity, along with liver mass and body composition changes, would be expected to affect the pharmacokinetics of tacrolimus in the elderly. However, interindividual variation in these processes may mask any changes caused by aging. More investigation is needed into the impact aging has on CYP and P-glycoprotein activity and expression. No single-dose, intense blood-sampling study has specifically compared the pharmacokinetics of tacrolimus across different patient age groups. However, five population pharmacokinetic studies, one in kidney, one in bone marrow and three in liver transplant recipients, have investigated age as a co-variate. None found a significant influence for age on tacrolimus bioavailability, volume of distribution or clearance. The number of elderly patients included in each study, however, was not documented and may have been only small. It is likely that inter- and intraindividual pharmacokinetic variability associated with tacrolimus increase in elderly populations. In addition to pharmacokinetic differences, donor organ viability, multiple co-morbidity, polypharmacy and immunological changes need to be considered when using tacrolimus in the elderly. Aging is associated with decreased immunoresponsiveness, a slower body repair process and increased drug adverse effects. Elderly liver and kidney transplant recipients are more likely to develop new-onset diabetes mellitus than younger patients. Elderly transplant recipients exhibit higher mortality from infectious and cardiovascular causes than younger patients but may be less likely to develop acute rejection. Elderly kidney recipients have a higher potential for chronic allograft nephropathy, and a single rejection episode can be more devastating. There is a paucity of information on optimal tacrolimus dosage and target trough concentration in the elderly. The therapeutic window for tacrolimus concentrations may be narrower. Further integrated pharmacokinetic-pharmacodynamic studies of tacrolimus are required. It would appear reasonable, based on current knowledge, to commence tacrolimus at similar doses as those used in younger patients. Maintenance dose requirements over the longer term may be lower in the elderly, but the increased variability in kinetics and the variety of factors that impact on dosage suggest that patient care needs to be based around more frequent monitoring in this age group.

Timing affects the efficacy of LDL immunization on atherosclerotic lesions in apo E (−/−) mice

BACKGROUND

Immunization of animals with LDL reduces atherosclerosis. However, whether the timing of immunization affects its efficacy is not known. In this study, we evaluated the influence of timing of immunization on the athero-protective effects of LDL immunization in apo E (-/-) mice.

METHODS AND RESULTS

Hypercholesterolemic apo E (-/-) mice were immunized with native LDL (nLDL) at age of 6-7 weeks old or at 20 weeks old. Compared to adjuvant group, mice that were immunized at the age of 6-7 weeks developed significantly smaller aortic sinus plaques with reduced gelatinolytic activity and increased collagen content. This was associated with an increase of oxidized LDL (oxLDL) antibody titer and a marked decrease in splenic IL-4 mRNA expression. Immunization at 20 weeks of age also increased oxLDL antibody titer but did not reduce plaque size, gelatinolytic activity or collagen content but resulted in a modest decrease in macrophage infiltration. Late immunization did not alter splenic IL-4 mRNA expression.

CONCLUSIONS

Our findings demonstrate that, only early nLDL immunization modulates humoral and cellular immune responses and affects plaques size and composition in apo E (-/-) mice, indicating the critical importance of timing of immunization for its antiatherogenic efficacy.

Increased incidence of pathological and clinical prostate cancer with age: age related alterations of local immune surveillance

PURPOSE

The incidence of prostate cancer dramatically increases with age. The etiology still awaits elucidation, and the question as to why it is so prominently a disease of aging remains unanswered. We offer an explanation by suggesting an age related deficient immune surveillance.

MATERIALS AND METHODS

Reports published in the scientific literature with relevance to cancer and immunity, immune senescence, blood-prostate barrier and immune privilege were identified using MEDLINE.

RESULTS

The existence of a blood-prostate barrier is a fair assumption, and the prostate may be considered an immune privileged site. With aging the prostate, a priori immunologically under surveilled, probably becomes more and more so. There is impaired function, transmigration and probably penetration into the gland of natural killer and other immune competent cells due to the onset of immune senescence coupled with impaired diapedesis and possible age related alterations in the blood-prostate barrier.

CONCLUSIONS

Apparently, with aging the immune surveillance of the already immune privileged prostate is progressively and further affected. This condition may result in the inability of the gland to eradicate emergent malignant cells.

Aging is associated with increased human T cell CC chemokine receptor gene expression

Leukocyte chemokine receptors (CR) are central to the pathogenesis of many human diseases, including human immunodeficiency virus-1 (HIV-1) infection. Elderly individuals infected with the HIV-1 virus have a shorter disease-free interval and worse clinic outcome. However, the reasons for this are unclear. We recently reported increased CC chemokine receptor (CCR) expression in CD4+ T cells in aged mice, but it is not known if similar changes occur in humans. In addition, it is unclear if the observed differences are related to aged-related expansion in the memory T cell compartment. In this report, we examined the effects of aging on CCR gene expression in human peripheral blood mononuclear cells (PBMCs), CD4+ T cells, and naive/memory T cells. Aging is found to be associated with increased CCR1-5 expression in PBMCs and CD4+ T cells. In addition, although the age-related increases in CCR expression occurred in both naive and memory T cells, the greatest changes were seen in the memory T cell subset. We propose that the observed aging-associated increase in T cell chemokine receptor expression may contribute to the worse clinical outcome of T cell chemokine receptor-dependent disease, such as HIV-1 infection, in the elderly.

Gender differences in mortality after hip fracture: the role of infection

Possible explanations for the observed gender difference in mortality after hip fracture were examined in a cohort of 804 men and women. Mortality during 2 years after fracture was identified from death certificates. Men were twice as likely as women to die, and deaths caused by pneumonia/influenza and septicemia showed the greatest increase.

INTRODUCTION

Men are more likely to die after hip fracture than women. Gender differences in predisposing factors and causes of death have not been systematically studied.

MATERIALS AND METHODS

Participants (173 men and 631 women) in the Baltimore Hip Studies cohort enrolled in 1990 and 1991, at the time of hospitalization for hip fracture, were followed longitudinally for 2 years. Cause-specific mortality 1 and 2 years after hip fracture, identified from death certificates, was compared by gender and to population rates.

RESULTS AND CONCLUSIONS

Men were twice as likely as women to die during the first and second years after hip fracture (odds ratio [OR], 2.28; 95% CI, 1.47, 3.54 and OR, 2.21; 95% CI, 1.48, 3.31). Prefracture medical comorbidity, type of fracture, type of surgical procedure, and postoperative complications did not explain the observed difference. Greatest increases in mortality, relative to the general population, were seen for septicemia (relative risk [RR], 87.9; 95% CI, 16.5, 175 at 1 year and RR, 32.0; 95% CI, 7.99, 127 at 2 years) and pneumonia (RR, 23.8; 95% CI, 12.8, 44.2 at 1 year and RR, 10.4; 95% CI, 3.35, 32.2 at 2 years). The magnitude of increase in deaths caused by infection was greater for men than for women in both years. Mortality rates for men and women were similar if deaths caused by infection were excluded (3.46 [1.79, 6.67] and 2.47 [1.63, 3.72] at 1 year and 0.96 [0.48, 1.91] and 1.26 [0.80, 1.98] at 2 years). Deaths related to infections (pneumonia, influenza, and septicemia) seem to be largely responsible for the observed gender difference. In conclusion, an increased rate of death from infection and a gender difference in rates persists for at least 2 years after the fracture.

Age and Risk of Pulmonary Arterial Hypertension in Scleroderma*

STUDY OBJECTIVES

To investigate whether age at disease onset is a risk factor for pulmonary arterial hypertension (PAH) in scleroderma.

SETTING

Scleroderma center.

PATIENTS

Seven hundred nine consecutive scleroderma patients who underwent echocardiography.

MEASUREMENTS

The risk of PAH associated with age at disease onset was modeled as both a continuous and categorical variable. Risk estimates were adjusted for sex, race, scleroderma subtype, disease duration, smoking status, FVC, anticentromere and antitopoisomerase I antibody status.

RESULTS

Overall, 274 patients (38.6%), 272 patients by Doppler echocardiography and 2 patients by M-mode echocardiography, had PAH at baseline or during follow-up. There were 114 patients with mild PAH (right ventricular systolic pressure [RVSP], 36 to 45 mm Hg), 66 patients with moderate PAH (RVSP, 46 to 55 mm Hg), and 92 patients with severe PAH (RVSP > or =56 mm Hg). A 52% increase in risk of PAH was demonstrated for every 10 years of age at disease onset (odds ratio [OR], 1.52; 95% confidence interval [CI], 1.31 to 1.76). In addition, there was a twofold greater risk of PAH (OR, 2.30; 95% CI, 1.32 to 3.99) for late-onset (age > or =60 years) vs earlier-onset (< 60 years) disease. These associations remained evident and were somewhat strengthened when the analyses were restricted to patients with moderate and severe PAH.

CONCLUSIONS

We identified increasing age at scleroderma onset as a risk factor for PAH. Vigilance among these high-risk patients may provide an opportunity to intervene prior to development of irreversible pulmonary vascular disease.