Selected artcles April 2016
Ageing and lymphocyte subsets
Effects of Ageing on the Immune System: Infants to Elderly
R. Valiathan, M. Ashman and D. Asthana
Here, researchers from the University of Miami Miller School of Medicine retrospectively analysed the data for complete blood count (CBC) and lymphocyte subsets from infant to elderly age groups (infants, children, adolescents, adults and elderly) to determine changes taking place during ageing.
The researchers show that B cells continuously decrease from childhood, which highlights the importance of establishing age specific reference points.
Ranjini Valiathan is a postdoctoral associate in the group, and was responsible for the lab work, analysis and writing of the article.
– The NK cells represent an important component of the innate immune response against infection and we observed a significant decrease in NK cell percentages from infancy to adolescent and then an increase from adults to the elderly population, she explains.
In addition, the researchers investigated levels of epidermal growth factor, EGF, involved in the growth and proliferation of several types of cells in the central nervous system.
– In our analysis there were decreased plasma EGF levels in elderly individuals compared to adults, Ranjini Valiathan says. High levels of EGF are present in the CNS and it plays a crucial role in controlling proliferation and differentiation of nervous tissue during neurogenesis. Additionally, it is also a major factor in promoting wound healing by expression at sites of injury, which inhibits the activity of nitric oxide synthase, preventing inflammation.
– This study revealed the changes in many different lymphocyte subsets and blood count parameters during ageing process and shows us the requirement of establishing age specific reference points, she concludes.
On obesity and inflammation
Weight Gain Alters Adiponectin Receptor 1 Expression on Adipose Tissue-Resident Helios+ Regulatory T Cells
P. Ramos-Ramírez, C. Malmhäll, K. Johansson, J. Lötvall and A. Bossios
In a study by researchers from the Krefting Research Center at the University of Gothenburg it is found that T-regulatory cells in adipose tissue express Helios, a transcription factor that it has been suggested as a marker for thymic-derived T-regulatory cells.
Obesity has increased significantly in recent decades and has become the largest global chronic health problem in adults. It is now recognized that in addition to its role as a storage depot for lipids, adipose tissue also secretes diverse proteins that influence metabolism as well as the immune system.
The aim of the present study was to evaluate the adiponectin receptor 1 (AdipoR1) expression in adipose tissue-resident T-regulatory cells and to evaluate the effect of weight gain on this expression.
The researchers found that adipose tissue-resident T-regulatory cells express high levels of AdipoR1 compared with their circulating counterparts in the spleen, suggesting an adipose tissue-specific function of AdipoR1-positive T-regulatory cells.
Patricia Ramos-Ramirez, originating from Mexico came to Sweden to do a postdoc at the Krefting Research Center, in the group of Dr Apostolos Bossios, associate professor at the University of Gothenburg.
– In this work, I was involved every aspect, from the experimental design and maneuverers, such as tracking weight gain of the mice, the collection and processing of samples, analysis of data and of preparing the manuscript, she says.
Patricia Ramos-Ramirez enjoyed the data analysis of the research very much.
– After seeing tiny cells doing, or not, their work, you can understand some of the mechanisms leading to the development of pathologies, as in this case the obesity, she says. The most fun during a project is when you find a possible answer to your initial question, but often you find an answer and also more questions, and it is very exciting to generate new hypotheses and ways to understand how cells work in homeostasis or during pathologies, as in our study, during obesity, she concludes.
Obesity is a growing public health problem, and understanding as the low-grade inflammation during obesity is regulated could be a potential subject to control it.