Neopterin production in relation to COVID-19 in the Haut-Ogooué Province, Gabon

Abstract

Abstract Background At the beginning of the COVID-19 pandemic, the immunological aspects of the SARS-CoV-2 were not at the forefront of research in sub-Saharan Africa. In this context, this study aimed to investigate the association between plasma neopterin concentrations and COVID-19 infection, with a focus on changes over time and age-related changes in immune response. Methods We included a cohort of 325 individuals, consisting of 124 with COVID-19 and 201 healthy controls between June to August 2020. Whole blood and associated symptoms and comorbidities were collected from all individuals at the time of enrollment and longitudinally over 28 days. Concentrations of plasma neopterin were measured using a commercial competitive neopterin ELISA (Neopterin ELISA, IBL International GmbH, Germany). Results We found elevated plasma neopterin concentration in individuals with COVID-19 (mean ± SD: 50.0 ± 15) compared to healthy controls (mean ± SD: 34.0 ± 1.6), indicating active immune responses in COVID-19 cases. Longitudinal analysis showed a decline in neopterin levels over time, at the initial sampling (first day) it was 42.00 ± 12.00 nmol/l, measure at day 10 it was 30.00 ± 02.00 nmol/l and at day 14 it was 25.00 ± 05.00 nmol/l. Moreover, a significant positive correlation was found between plasma neopterin concentrations and age. This age-related increase in neopterin may indicate a more pronounced immune response in older individuals. Conclusion This study provides evidence of an association between neopterin levels and COVID-19 infection, and indicates neopterin as a marker capable of diagnosing age related changes in older individuals compared to young one. Our study suggests also that neopterin may serve as a valuable biomarker for assessing the immune response and monitoring disease progression during an outbreak.