An assessment of nutritional status in children of rural, northern KwaZulu-Natal province

Background: Childhood malnutrition in South Africa is largely perceived as one of undernutrition, with the opposite end of the spectrum (overnutrition) being evidenced in the increasing prevalence of childhood obesity, demonstrated to be associated with chronic metabolic diseases in adulthood. Targeting childhood malnutrition is a potential interventional strategy to prevent non-communicable diseases amongst adults. As the prevalence of malnutrition (undernutrition and overnutrition) in rural, northern KwaZulu-Natal province, South Africa, is largely unknown, this study aimed to determine the baseline nutritional status of children attending primary healthcare facilities within the Bethesda Hospital catchment area.Methods: This quantitative, cross-sectional study included children aged 6 weeks to 19 years, attending any primary healthcare clinics for over a 3 months period. Anthropometric measurements were obtained to categorise the children according to the World Health Organisation’s (WHO) nutritional classifications.Results: Stunting in children aged less than 5 years was found to be lower (14%) than nationally representative studies (27%); however, 14.4% of the infants aged 6 weeks to 5 months were overweight, increasing to 32.3% in those aged 14–19 years. Males in the 6-weeks to 5-month age group were more likely to be overweight/obese and stunted than females in the same age group.Conclusion: Undernutrition is showing a downward trend, which is a testament to initiatives to reduce food insecurity amongst the poor. However, the emerging upward trend of overweight/obesity in children of all ages, indicates the need to have a national discussion on over- and undernutrition, its causes and implications

Clonally expanded CD8 T cells patrol the cerebrospinal fluid in Alzheimer’s disease

Alzheimer's disease is an incurable neurodegenerative disorder in which neuroinflammation has a critical function1. However, little is known about the contribution of the adaptive immune response in Alzheimer's disease2. Here, using integrated analyses of multiple cohorts, we identify peripheral and central adaptive immune changes in Alzheimer's disease. First, we performed mass cytometry of peripheral blood mononuclear cells and discovered an immune signature of Alzheimer's disease that consists of increased numbers of CD8+ T effector memory CD45RA+ (TEMRA) cells. In a second cohort, we found that CD8+ TEMRA cells were negatively associated with cognition. Furthermore, single-cell RNA sequencing revealed that T cell receptor (TCR) signalling was enhanced in these cells. Notably, by using several strategies of single-cell TCR sequencing in a third cohort, we discovered clonally expanded CD8+ TEMRA cells in the cerebrospinal fluid of patients with Alzheimer's disease. Finally, we used machine learning, cloning and peptide screens to demonstrate the specificity of clonally expanded TCRs in the cerebrospinal fluid of patients with Alzheimer's disease to two separate Epstein-Barr virus antigens. These results reveal an adaptive immune response in the blood and cerebrospinal fluid in Alzheimer's disease and provide evidence of clonal, antigen-experienced T cells patrolling the intrathecal space of brains affected by age-related neurodegeneration