Quantitative Analysis of Phagocytosis in Whole Blood Using Double Staining and Visualization.

Phagocytosis is an essential innate immunity function in humans and animals. A decrease in the ability to phagocytize is associated with many diseases and aging of the immune system. Assessment of phagocytosis dynamics requires quantification of bacteria inside and outside the phagocyte. Although flow cytometry is the most common method for assessing phagocytosis, it does not include visualization and direct quantification of location of bacteria. Here, we used double-labeled Escherichia coli cells to evaluate phagocytosis by flow cytometry (cell sorting) and confocal microscopy, as well as employed image cytometry to provide high-throughput quantitative and spatial recognition of the double-labeled E. coli associated with the phagocytes. Retention of pathogens on the surface of myeloid and lymphoid cells without their internalization was suggested to be an auxiliary function of innate immunity in the fight against infections. The developed method of bacterial labeling significantly increased the accuracy of spatial and quantitative measurement of phagocytosis in whole blood and can be recommended as a tool for phagocytosis assessment by image cytometry.

Deep Learning for Cell Migration in Nonwoven Materials and Evaluating Gene Transfer Effects following AAV6-ND4 Transduction.

Studying cell settlement in the three-dimensional structure of synthetic biomaterials over time is of great interest in research and clinical translation for the development of artificial tissues and organs. Tracking cells as physical objects improves our understanding of the processes of migration, homing, and cell division during colonisation of the artificial environment. In this study, the 3D environment had a direct effect on the behaviour of biological objects. Recently, deep learning-based algorithms have shown significant benefits for cell segmentation tasks and, furthermore, for biomaterial design optimisation. We analysed the primary LHON fibroblasts in an artificial 3D environment after adeno-associated virus transduction. Application of these tools to model cell homing in biomaterials and to monitor cell morphology, migration and proliferation indirectly demonstrated restoration of the normal cell phenotype after gene manipulation by AAV transduction. Following the 3Rs principles of reducing the use of living organisms in research, modeling the formation of tissues and organs by reconstructing the behaviour of different cell types on artificial materials facilitates drug testing, the study of inherited and inflammatory diseases, and wound healing. These studies on the composition and algorithms for creating biomaterials to model the formation of cell layers were inspired by the principles of biomimicry.

Reliable Hallmarks and Biomarkers of Senescent Lymphocytes.

The phenomenon of accumulation of senescent adaptive immunity cells in the elderly is attracting attention due to the increasing risk of global epidemics and aging of the global population. Elderly people are predisposed to various infectious and age-related diseases and are at higher risk of vaccination failure. The accumulation of senescent cells increases age-related background inflammation, "Inflammaging", causing lymphocyte exhaustion and cardiovascular, neurodegenerative, autoimmune and cancer diseases. Here, we present a comprehensive contemporary review of the mechanisms and phenotype of senescence in the adaptive immune system. Although modern research has not yet identified specific markers of aging lymphocytes, several sets of markers facilitate the separation of the aging population based on normal memory and exhausted cells for further genetic and functional analysis. The reasons for the higher predisposition of CD8+ T-lymphocytes to senescence compared to the CD4+ population are also discussed. We point out approaches for senescent-lymphocyte-targeting markers using small molecules (senolytics), antibodies and immunization against senescent cells. The suppression of immune senescence is the most relevant area of research aimed at developing anti-aging and anti-cancer therapy for prolonging the lifespan of the global population.

Age-Related Changes in the Clustering of Blood Populations in Cynomolgus Monkeys Depend on Sex and Immune Status.

Non-anthropoid primates cynomolgus monkeys (Macaca fascicularis), also known as crab-eating macaques, are increasingly used in biomedical and preclinical studies due to their evolutionary proximity to humans, sharing similar diets, infectious and senile diseases. Age-related changes and sexual dimorphism of the immune system of C. monkeys have not been sufficiently characterized in literature, though age and sex differences affect the course of diseases and sensitivity to medications. Aging in C. monkeys is accompanied by an increase in CD3+CD4+CD8+ (DP-T) cells, plasma B-cells, and a decrease in platelets. Erythromyeloid bias has also been noticed in older animals. There was an increase in eosinophils, haematocrit (HCT) and haemoglobin concentration (HGB). Senile decline in the function of the immune system had sex differences. An increase in the number of monocytes, cytotoxic lymphocytes (CTL) and a decrease in the T-helper population were more pronounced in older females. A significant reduction in the number of B-cells and activated T-cells was detected in males only. A moderate correlation with the regression model of aging was established for DP-T, HCT and HGB. The reduction in the B cells count in males and the increase in CTL level in females are moderately correlated with age. Other blood cell populations did not show significant correlations in the regression models due to their high sample variability. The novel cell population CD3-CD20loCD16/CD56+, presumably NK-cells subset, was revealed. This cell population demonstrated an increase trend with age in both sexes. Population-statistical age norms for different sexes for young and very old macaques were established. The blood population clusters associated with sex and immune status in older animals were also identified.

Use of Personal Resources May Influence the Rate of Biological Aging Depending on Individual Typology.

Individual hobbies and interests, the ways of spending leisure time develop personal resources influencing health and wellbeing. The literature analysis helped selecting thirteen personal resources that also affect the rate of aging: sports, order, creativity, intellect, handwork, kindness, Humor, spirituality, risk, nature, achievements, optimism, communication. In 1632 people, (840 women and 792 men) personal resources were assessed using a questionnaire developed in-house. Biological age was determined by health indicators. The personal typology was determined by testing functional asymmetry, physique, interaction style, emotionality, profession, marital status, gender, age, and place of residence. The data were processed by correlation and cluster analysis and methods of automatic artificial neural networks (ANN). Personal resources were used as input continuous variables. Personality types were used as input categorical variables. The index of relative biological aging (RBA) was applied as an output continuous variable. We also calculated the correlation between the RBA index and the applied personal resources in different types of personalities. For most female types including investigative occupations, psychomotor emotionality, living in urban areas, asthenic physique, negative correlations were found between most personal resources and the aging index. In men, resources that slow down aging are found only for certain types: enterprising and conventional professions, ambidexter and left-handed, intellectual emotionality, athletic physique. In conclusion, with the help of the trained ANN, we selected personal resources that slow down aging. For women of all types, there are common resources reducing RBA index including nature, intellect, and achievements. For men, ANN was unable to find common resources that slow down aging. However, with an individual selection of resources, a trained neural network gives a favorable forecast of the ability to slow down the biological aging of a particular man by changing his hobbies and interests and ways of spending free time.

Religiosity, Spirituality and Biopsychological Age of Professionals in Russia.

The challenges of modern civilization resulted in the premature biological and psychological aging of professionals of working age. This phenomenon raises both medical and psychological problems associated with personality factors that affect psychobiological maturity and the rate of aging. The influence of religiosity and spirituality on biopsychological age remains the least studied area of psychology. Progress in this area will help to identify the components of religiosity-predictors of the aging rate of professionals. The sample included 295 people (148 women) aged 24 to 54 years (average age 31.7 years) and consisted of Christians (67.12%), Muslims (5.76%), Buddhists, deists, Shintoists, etc., (7.79%) and atheists (17.29%). The average work experience was 9 years. Using correlation analysis and methods of multivariate linear regression and t-test for independent samples, we found that the religiosity of professionals increases with natural aging and deterioration of their physical condition and does not depend on gender. Religiosity to a greater extent affects psychological age, the indicator of the psychobiological maturity of a professional and, to a lesser extent, biological age. Most of the indicators of religiosity are inherent in a person who is more mature in psychobiological terms. The biological age of professionals increases due to asthenic experiences, while gaining faith in God, unusual religious experiences and the existential meaning of life can reduce it. An increase in the spirituality of professionals is associated with a slowdown in the rate of biological aging.

Comparative Dynamics of Individual Ageing among the Investigative Type of Professionals Living in Russia and Russian Migrants to the EU Countries.

The goal of this study was to uncover the influence of professional activity, migration, and gender on dynamics of subjective age and ageing biomarkers. We examined the representatives of investigative types of professions (ITP), 30-75 years old in Russia, (101/62 women), and Russian migrants to the European Union, (101/56 women). ITPs appeared to be ageing slower than statistical standards; men age faster than women; the pre-retirement group (51-65 years old) showed acceleration of relative biological ageing in the Russian sample (women +4.5 years, men +10.7 years) against the EU sample, suggesting a boost of pre-retirement stress in Russia; subjectively, Russian people (51-65 years old) feel close to their chronological age, while EU people perceive themselves far below their calendar age (men-lower by 20.4, women-lower by 10.9 years). The subjective ageing depends on the country of residence, while biological ageing depends on occupation, gender, and negative expectations of retirement.

Dissecting the role of lymphotoxin in lymphoid organs by conditional targeting.

Mice with inactivation of lymphotoxin beta receptor (LTbetaR) system have profound defects in the development and maintenance of peripheral lymphoid organs. As surface LT is expressed by lymphocytes, natural killer cells, and lymphoid tissue-initiating cells as well as by some other cell types, we dissected cell type-specific LT contribution into the complex LT-deficient phenotype by conditional gene targeting. B-LTbeta knockout (KO) mice displayed an intermediate phenotype in spleen as compared with mice with complete LTbeta deficiency. In contrast, T-LTbeta KO mice displayed normal structure of the spleen. However, inactivation of LTbeta in both T and B cells resulted in additional defects in the structure of the marginal zone and in the development of follicular dendritic cells in spleen. Structure of lymph nodes (LN) and Peyer's patches (PP) was normal in both B-LTbeta KO and T- and B-LTbeta KO mice, except that PPs were of reduced size. When compared across the panel of lymphocyte-specific LT KOs, the defects in antibody responses to T-cell-dependent antigens correlated with the severity of defects in spleen structure. Expression of CCL21 and CCL19 chemokines was not affected in spleen, LN and PP of B-LTbeta KO and T- and B-LTbeta KO mice, while CXCL13 was slightly reduced only in spleen. Collectively, our data suggest the following: (i). requirements for LT signaling to support architecture of spleen, LN and PP are different; (ii). LT complex expressed by B cells plays a major role in the maintenance of spleen structure, while surface LT expressed by T cells provides a complementary but distinct signal; and (iii). in a non-transgenic model, expression of lymphoid tissue chemokines is only minimally dependent on the expression of surface LT complex on B and T lymphocytes.