Seasonal changes in non-human animals and seasonal affective disorder (SAD) in humans are associated with immune activation in winter relative to summer. We intended to measure seasonal variation in neopterin, a marker of cellular immunity, and its interactions with gender and seasonality of mood. We studied 320 Amish from Lancaster, PA, USA (men=128; 40%) with an average age [Standard deviation (SD)] of 56.7 (13.9) years. Blood neopterin level was measured with enzyme-linked immunosorbent assay (ELISA). Seasonality was measured with Seasonal Pattern Assessment Questionnaire (SPAQ). Statistical analysis included analysis of covariance (ANCOVAs) and multivariate linear regression. We also investigated interactions of seasonal differences in neopterin with gender, seasonality scores and estimation of SAD diagnosis. We found a significantly higher neopterin level in winter than in summer (p=0.006). There were no significant gender or seasonality interactions. Our study confirmed the hypothesized higher neopterin level in winter. A cross sectional design was our major limitation. If this finding will be replicated by longitudinal studies in multiple groups, neopterin could be used to monitor immune status across seasons in demographically diverse samples, even if heterogeneous in gender distribution, and degree of seasonality of mood.

中文翻译：

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旧秩序阿米什人血液中新蝶呤水平的季节性

非人类动物的季节性变化和人类的季节性情感障碍 (SAD) 与冬季相对于夏季的免疫激活有关。我们打算测量新蝶呤（一种细胞免疫的标志物）的季节性变化，以及它与性别和情绪季节性的相互作用。我们研究了来自美国宾夕法尼亚州兰开斯特的 320 名阿米什人（男性=128；40%），平均年龄 [标准差 (SD)] 为 56.7 (13.9) 岁。用酶联免疫吸附试验（ELISA）测量血液中的新蝶呤水平。使用季节性模式评估问卷 (SPAQ) 测量季节性。统计分析包括协方差分析（ANCOVA）和多元线性回归。我们还研究了新蝶呤的季节性差异与性别、季节性评分和 SAD 诊断估计的相互作用。我们发现冬季的新蝶呤水平显着高于夏季（p=0.006）。没有显着的性别或季节性相互作用。我们的研究证实了假设的冬季新蝶呤水平较高。横截面设计是我们的主要限制。如果这一发现将在多个组的纵向研究中得到复制，那么新蝶呤可用于监测人口多样化样本中跨季节的免疫状态，即使性别分布和情绪的季节性程度存在异质性。