Urinary neopterin reflects immunological variation associated with age, helminth parasitism, and the microbiome in a wild primate

Abstract

Neopterin, a product of activated white blood cells, is a marker of nonspecific inflammation that can capture variation in immune investment or disease-related immune activity and can be collected noninvasively in urine. Mounting studies in wildlife point to lifetime patterns in neopterin related to immune development, aging, and certain diseases, but rarely are studies able to assess whether neopterin can capture multiple concurrent dimensions of health and disease in a single system. We assessed the relationship between urinary neopterin stored on filter paper and multiple metrics of health and disease in wild geladas (Theropithecus gelada), primates endemic to the Ethiopian highlands. We tested whether neopterin captures age-related variation in inflammation arising from developing immunity in infancy and chronic inflammation in old age, inflammation related to intramuscular tapeworm infection, helminth-induced anti-inflammatory immunomodulation, and perturbations in the gastrointestinal microbiome. We found that neopterin had a U-shaped relationship with age, no association with larval tapeworm infection, a negative relationship with metrics related to gastrointestinal helminth infection, and a negative relationship with microbial diversity. Together with growing research on neopterin and specific diseases, our results demonstrate that urinary neopterin can be a powerful tool for assessing multiple dimensions of health and disease in wildlife.

Modulation of cell-mediated immunity during pregnancy in wild bonobos

“…We found that urinary neopterin levels decreased throughout the day (table 1), as found in other primates [32,38,[41][42][43][44]. This finding emphasizes the importance of considering sampling time in future urinary neopterin studies.…”

The immunity gap in primates

“…73,83 In wild geladas, urinary neopterin levels were highest in both the youngest and oldest individuals in the population, indicating that it marks inflammation related to both immune system development and immunosenescence. 84 Another way to examine immunosenescence and longevity in primates is through a clinical biomarker for inflammation and physiological stress, neutrophil-tolymphocyte ratio, or NLR. This ratio typically increases with age in healthy human populations, suggesting a greater predisposition to inflammation and disease with age in humans.…”

Neopterin, the Cell-Mediated Immune Response Biomarker, in Inflammatory Periodontal Diseases: A Narrative Review of a More than Fifty Years Old Biomarker

“…In 1967, Np was isolated in human urine by Sakurai A. and Goto for the first time [7]. It has been extensively studied in wide-spectrum inflammatory diseases, including viral, bacterial, and parasite infections, cardiovascular diseases, autoimmune diseases, and malignant tumours [8][9][10][11][12][13][14].…”