INTRODUCTION In effusion cytology, immunocytochemistry is a useful staining approach to provide important information for diagnosis. Effusion cytology is performed not only for pleural effusions and ascites but also for peritoneal and needle washing from fine needle aspirations or instruments. Although various solutions are used for washing cytology, the effect of the solution type on immunocytochemical reactivity is not fully understood. In this study, we examined the immunocytochemical reactivity of cytological samples after storage in various solutions. METHODS Cell block specimens were obtained from ascites of patients with peritoneal cancer and pleural effusions of patients with diffuse malignant mesothelioma. Various solutions, including physiological saline (PS), Ringer solution, a low-molecular-weight dextran L injection, Voluven 6% solution, Mixid L injection, RPMI-1640 medium, and horse serum were added to the sediment layers of aliquots. All samples were kept at 4°C, and aliquots were subsequently processed at specific time points (0, 1, 2, 4, 7, and 14 days). Formalin-fixed, paraffin-embedded, cell block samples were prepared for immunocytochemical staining. Immunocytochemical results were analyzed for differences in the percentages of positive cells, using the effusion sample stored for 1 h as standard (100%). RESULTS For all solutions other than PS, the median and central 50% of values were <100% (with respect to the effusion sample as a standard) after 1 h of storage. Immunoreactivity decreased for most solutions as time progressed. CONCLUSION Of note, immunocytochemistry results obtained using a washing solution are different from those using an effusion sample. For cytology, when a washing solution was used or when a sample was stored for a long time, the accuracy of the immunocytochemical results was low.

中文翻译：

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储存溶液类型和长期储存对细胞免疫反应性的影响。

简介在积液细胞学中，免疫细胞化学是一种有用的染色方法，可为诊断提供重要信息。积液细胞学检查不仅用于胸腔积液和腹水，还用于从细针穿刺或器械中冲洗腹膜和针头。尽管各种溶液用于洗涤细胞学，但溶液类型对免疫细胞化学反应性的影响尚未完全了解。在这项研究中，我们检查了储存在各种溶液中后细胞学样品的免疫细胞化学反应性。方法从腹膜癌患者的腹水和弥漫性恶性间皮瘤患者的胸腔积液中获取细胞块标本。各种溶液，包括生理盐水（PS），林格溶液，低分子量右旋糖酐L注射液，将等体积的6％溶液，Mixid L注射液，RPMI-1640培养基和马血清添加到等分试样的沉淀层中。将所有样品保持在4°C，然后在特定时间点（0、1、2、4、7和14天）处理等分试样。制备福尔马林固定，石蜡包埋的细胞块样品用于免疫细胞化学染色。免疫细胞化学结果分析阳性细胞百分率的差异，以储存1 h的渗出样品为标准（100％）。结果对于PS以外的所有其他溶液，储存1 h后，中值和中心值的50％均小于100％（相对于以渗出液为标准的溶液）。随着时间的流逝，大多数溶液的免疫反应性降低。结论：使用洗涤液获得的免疫细胞化学结果与使用积液样品获得的结果不同。对于细胞学，当使用洗涤液或长时间保存样品时，免疫细胞化学结果的准确性较低。