Project description:Seasonal influenza contributes to a substantial disease burden annually, resulting in approximately 10 million hospital visits and 50 thousand deaths in a typical year in the US. 90% of the annual mortality from influenza occurs in people over the age of 65. While influenza vaccination is the best protection against the virus, it is less effective for the elderly. This may be due to differences in the quantity or type of B cells induced by vaccination in older individuals. To investigate this possibility, we leveraged recent development in single-cell technology that allows for simultaneous measurement of both gene expression profile and the B cell receptor (BCR) at single-cell resolution. Pre- and post-vaccination peripheral blood B cells were sorted from three young and three older adults who responded to the inactivated influenza vaccine and were profiled using single-cell RNAseq with paired BCR sequencing. At pre-vaccination, we observed a higher somatic hypermutation frequency and a higher abundance of activated B cells in older adults than in young adults. Following vaccination, young adults mounted a more clonal response than older adults. The response involved a mix of plasmablasts, activated B cells, and resting memory B cells in both age groups. The response in young adults was dominated by expansion in plasmablasts, while the response in older adults also involved activated B cells. We observed a consistent change in gene expression in plasmablasts after vaccination between age groups but not in the activated B cells. These quantitative and qualitative differences in the B cell response may provide insights into the age-related change of influenza vaccination response.
Project description:Seasonal influenza contributes to a substantial disease burden annually, resulting in approximately 10 million hospital visits and 50 thousand deaths in a typical year in the US. 90% of the annual mortality from influenza occurs in people over the age of 65. While influenza vaccination is the best protection against the virus, it is less effective for the elderly. This may be due to differences in the quantity or type of B cells induced by vaccination in older individuals. To investigate this possibility, we leveraged recent development in single-cell technology that allows for simultaneous measurement of both gene expression profile and the B cell receptor (BCR) at single-cell resolution. Pre- and post-vaccination peripheral blood B cells were sorted from three young and three older adults who responded to the inactivated influenza vaccine and were profiled using single-cell RNAseq with paired BCR sequencing. At pre-vaccination, we observed a higher somatic hypermutation frequency and a higher abundance of activated B cells in older adults than in young adults. Following vaccination, young adults mounted a more clonal response than older adults. The response involved a mix of plasmablasts, activated B cells, and resting memory B cells in both age groups. The response in young adults was dominated by expansion in plasmablasts, while the response in older adults also involved activated B cells. We observed a consistent change in gene expression in plasmablasts after vaccination between age groups but not in the activated B cells. These quantitative and qualitative differences in the B cell response may provide insights into the age-related change of influenza vaccination response.
Project description:The skeletal muscle system plays an important role in the independence of older adults. In this study we examine differences in the skeletal muscle transcriptome between healthy young and older subjects and (pre‐)frail older adults. Additionally, we examine the effect of resistance‐type exercise training on the muscle transcriptome in healthy older subjects and (pre‐)frail older adults. Baseline transcriptome profiles were measured in muscle biopsies collected from 53 young, 73 healthy older subjects, and 61 frail older subjects. Follow‐up samples from these frail older subjects (31 samples) and healthy older subjects (41 samples) were collected after 6 months of progressive resistance‐type exercise training. Frail older subjects trained twice per week and the healthy older subjects trained three times per week. At baseline genes related to mitochondrial function and energy metabolism were differentially expressed between older and young subjects, as well as between healthy and frail older subjects. Three hundred seven genes were differentially expressed after training in both groups. Training affected expression levels of genes related to extracellular matrix, glucose metabolism, and vascularization. Expression of genes that were modulated by exercise training was indicative of muscle strength at baseline. Genes that strongly correlated with strength belonged to the protocadherin gamma gene cluster (r = −0.73). Our data suggest significant remaining plasticity of ageing skeletal muscle to adapt to resistance‐type exercise training. Some age‐related changes in skeletal muscle gene expression appear to be partially reversed by prolonged resistance‐type exercise training. The protocadherin gamma gene cluster may be related to muscle denervation and re‐innervation in ageing muscle.
Project description:Listeria monocytogenes (Lm) kills up to 60% of infected newborns and adults >60 years of age but is asymptomic is most young adults. Monocytes are central to effective host defense against Lm. We hypothesize that age-dependent, pathway-specific differences in the ability of the monocyte to respond to Lm explain the increased risk of the newborn and older adult to severely suffer or die from Lm infection. To delineate age-dependent differences in innate responses that lead to differential infectious outcome, monocytes were isolated from cord blood (newborn) and peripheral blood (young and older adults) and infected with Lm. RNA was collected to determine age-dependent transcriptomic changes upon infection.
Project description:Listeria monocytogenes (Lm) kills up to 60% of infected newborns and adults >60 years of age but is asymptomic is most young adults. Monocytes are central to effective host defense against Lm. We hypothesize that age-dependent, pathway-specific differences in the ability of the monocyte to respond to Lm explain the increased risk of the newborn and older adult to severely suffer or die from Lm infection. To delineate age-dependent differences in innate responses that lead to differential infectious outcome, monocytes were isolated from cord blood (newborn) and peripheral blood (young and older adults) and infected with Lm. RNA was collected to determine age-dependent transcriptomic changes upon infection. Total RNA was isolated from purified human monocytes from 6 adult, 6 cord , 6 older adult blood donors that were infected with wild-type Listeria monocytogenes at a multiplicity of infected (MOI)=5 for 2 and 6 hr.
Project description:The aim of this investigation was to develop a global view of muscle transcriptional differences between older men and women and with aging for each sex. Muscle biopsies were obtained from the biceps brachii of young (age 19~28yrs) and older (age 65~76 yrs) men (7 young, 4 older) and women (7 young, 4 older). Total RNA was extracted and gene expression profiling was performed using the Affymetrix Human Genome U133 Plus 2 chip.
Project description:This study represents the first attempt to perform a profiling analysis of the intergenerational differences in the microRNAs (miRNAs) of melanocytic neoplasms in young adult and older adult groups. Our comparative miRNA profiling provides a novel characterization of the miRnomes of melanocytic neoplasms and melanomas of different age groups and identifies a set of potential diagnostic and potential clinico-pathologic biomarkers that may serve as targets for development of novel miR-based modalities in cancer diagnosis and treatment. An exploratory miRNA analysis of 666 miRs was conducted on formalin fixed and paraffin embedded tissues from 10 adults and 10 young adults including conventional melanoma and melanocytic neoplasms of uncertain biological significance. Age-matched benign melanocytic nevi were used as controls. The comparative profiling was intentionally performed at two extremes of age, i.e., less than 30 years (Mel 30) and greater than 60 years (Mel 60). Primary melanoma in patients greater than 60 years old was characterized by the increased expression of miRs regulating TLR-MyD88-NF-kappaB pathway (hsa-miR -199a), RAS/RAB22A pathway (hsa-miR-204); growth differentiation and migration (hsa-miR337), epithelial mesenchymal transition EMT (let-7b, hsa-miR-10b/10bSTAR(*)), invasion and metastasis (hsa-miR-10b/10bSTAR(*), hsa-miR-30a/e*, hsa-miR-29c*; cellular matrix components (hsa-miR-29c*); invasion-cytokinesis (hsa-miR 99b*) compared to melanoma of younger patients. miR 211 was dramatically downregulated in primary melanoma compared to nevi controls, decreased with increasing age and was among the miRs linked to metastatic processes and potentially targeting the inflammatory receptor CCR10; Primary melanoma in young adult patients was characterized by the increased expression of hsa-miR-449a and decreased expression of hsa-miR146b, hsa-miR 214*. Among the miRs expressed at higher levels in control nevi, compared to adult or young adult melanoma, was hsa-miR 574-3p. Only 2 miRs distinguished adult from young adult-pediatric nevi, hsa-miR374a* and has-miR-566. MiR 30a* appeared to be a strong marker of differentiation in clinical stages I-II adult and pediatric melanoma, and could predict classification of melanoma tissue in the two age groups. Furthermore, lymph node status in the two age groups was characterized by the statistically significant expression of hsa-miR-30a* and hsa-miR-204 (F-test, p-value <0.001).
Project description:Comparison of miRNA expression profiles in normal and malignant prostate tissues. Keywords: microarray analysis of microRNA expression profiles MicroRNA expression was compared between normal prostate tissue from either young subjects that died of trauma, or normal adjacent to tumor, and prostatic tumors in older prostate cancer patients. RNA was isolated from frozen tissue sections, enriched for the miRNA fraction, which was subsequently labeled and hybridized to miRNA microarrays for expression profiling analysis.
Project description:Streptococcus pneumoniae colonization in the upper respiratory tract is linked to pneumococcal disease development, predominantly affecting young children and older adults. As the global population ages and comorbidities increase, there is a heightened concern about this infection. We investigated the immunological responses of older adults to pneumococcal controlled human infection by analysing the cellular composition and gene expression in the nasal mucosa. Our comparative analysis with data from a concurrent study in younger adults revealed distinct gene expression patterns in older individuals susceptible to colonization, highlighted by neutrophil activation and elevated levels of CXCL9 and CXCL10. Unlike younger adults challenged with pneumococcus, older adults did not show recruitment of monocytes into the nasal mucosa following nasal colonization. However, older adults who were protected from colonization showed increased degranulation of CD8+ T cells, both before and after pneumococcal challenge. These findings suggest age-associated cellular changes, in particular enhanced mucosal inflammation, that may predispose older adults to pneumococcal colonization.