Fungal fragments are abundant immunoreactive bioaerosols that may outnumber the concentrations of intact spores in the air. To investigate the importance of Alternaria fragments as sources of allergens compared to Alternaria spores, we determined the levels of Alternaria spores and Alt a 1 (the major allergen in Alternaria alternata spores) collected on filters within three fractions of particulate matter (PM) of different aerodynamic diameter: (1) PM>10, (diameter>10 μm); (2) PM2.5-10 (2.5-10μm); (3) PM2.5 (0.12-2.5 μm). The airborne particles were collected using a three stage high-volume ChemVol cascade impactor during the Alternaria sporulation season in Poznań, Poland (30 d between 6 July and 22 September 2016). The quantification of Alt a 1 was performed using the enzyme-linked immunosorbent assay. High concentrations of Alt a 1 were recorded during warm and dry d characterized by high sunshine duration, lack of clouds and high dew point values. Atmospheric concentrations of Alternaria spores correlated significantly (r = 0.930, p < 0.001) with Alt a 1 levels. The highest Alt a 1 was recorded in PM2.5-10 (66.8 % of total Alt a 1), while the lowest in PM2.5 (<1.0 %). Significantly more Alt a 1 per spore (>30 %) was observed in PM2.5-10 than in PM>10. This Alt a 1 excess may be derived from sources other than spores, e.g. hyphal fragments. Overall, in outdoor air the major source of Alt a 1 are intact Alternaria spores, but the impact of other fungal fragments (hyphal parts, broken spores, conidiophores) cannot be neglected, as they may increase the total atmospheric Alt a 1 concentration.

中文翻译：

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主要的链格孢过敏原 Alt a 1 的粒径分布，来自空气传播的孢子和亚孢子碎片

真菌碎片是丰富的免疫反应性生物气溶胶，其数量可能超过空气中完整孢子的浓度。为了研究与链格孢子相比，链格孢碎片作为过敏原来源的重要性，我们确定了在不同颗粒物质 (PM) 的三个部分内的过滤器上收集的链格孢子和 Alt a 1（链格孢子孢子中的主要过敏原）的水平。气动直径：（1）PM>10，（直径>10μm）；(2) PM2.5-10 (2.5-10μm)；(3) PM2.5 (0.12-2.5 μm)。在波兰波兹南的链格孢属孢子形成季节（2016 年 7 月 6 日至 9 月 22 日之间的 30 天）期间，使用三级大容量 ChemVol 级联撞击器收集空气中的颗粒。Alt a 1 的定量使用酶联免疫吸附测定法进行。在温暖和干燥的 d 期间记录了高浓度的 Alt a 1，其特征是日照时间长、云量少和露点值高。链格孢属孢子的大气浓度与 Alt a 1 水平显着相关（r = 0.930，p < 0.001）。最高的 Alt a 1 记录在 PM2.5-10（占总 Alt a 1 的 66.8 %），而最低的是 PM2.5（<1.0 %）。在 PM2.5-10 中观察到的每个孢子的 A​​lt a 1 显着高于 PM>10（>30%）。该Alt a 1 过量可能来自孢子以外的来源，例如菌丝碎片。总体而言，在室外空气中，Alt a 1 的主要来源是完整的链格孢菌孢子，但其他真菌碎片（菌丝部分、破碎的孢子、分生孢子）的影响不容忽视，因为它们可能会增加大气 Alt a 1 的总浓度。