Colpodella species are free-living close relatives of apicomplexans that were recently reported to cause red blood cell infection in an immunocompromised human host and in a tick-borne human infection resulting in neurological symptoms. Unambiguous identification of the life cycle stages of Colpodella sp. using routine stains for light microscopy will aid rapid diagnosis in infections. Similarly, cells in culture and environmental samples can be rapidly identified by staining. Staining protocols are currently unavailable for cell detection by light microscopy. In this study, we investigated the feasibility of performing routine staining techniques for light microscopy for differentiating Colpodella sp. (ATCC 50594) and Bodo caudatus cysts in Hay medium cultures. We tested different basic and acidic dyes alone and in combination and also utilized a commercial trichrome staining protocol. The nonspecific fluorescent dye Calcofluor white was also evaluated. Staining times, dye concentrations, use of tap or distilled water rinses, use of a mordant and inclusion, or omission of decolorizers after staining were evaluated. We compared the intensity of color, clarity of morphological features, and cytoplasmic structures detected after staining. We report a new trichrome staining technique that allowed clear identification and differentiation of cyst stages of Colpodella sp. and B. caudatus. Immature Colpodella sp. cysts were identified as having an irregular, dual-colored (demilune), dark blue-purple and white appearance. Mature Colpodella sp. cysts stained dark red-blue and were identified in four-way mitotic division, while cysts of B. caudatus in diprotist or monoprotist (ATCC 30905) cultures were detected as spherical and red-pink in appearance.

中文翻译：

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新的三色染色剂可识别Colpodella sp。的囊肿。（Apicomplexa）和Bodo caudatus。

Colpodella物种是apicomplexans的自由生活近亲，最近有报道称apicomplexans在免疫功能低下的人类宿主和a传播的人类感染中引起红细胞感染，导致神经系统症状。Colpodella sp。生命周期阶段的明确鉴定。使用常规染色剂进行光学显微镜检查将有助于快速诊断感染。同样，可以通过染色快速鉴定培养物和环境样品中的细胞。染色方案目前尚不能用于通过光学显微镜进行细胞检测。在这项研究中，我们调查了进行常规显微镜染色技术以区分Colpodella sp。的可行性。（ATCC 50594）和Bodo caudatus干草培养基中的囊肿。我们单独或组合测试了不同的碱性和酸性染料，还利用了商业上的三色染色方案。还评估了非特异性荧光染料Calcofluor白色。评估了染色时间，染料浓度，使用自来水或蒸馏水冲洗，媒染剂的使用以及在染色后是否包含脱色剂。我们比较了染色后检测到的颜色强度，形态特征的清晰度和细胞质结构。我们报告了一种新的三色染色技术，该技术可以使Colpodella sp的囊肿阶段明确识别和区分。和B. caudatus。未成熟的阴道菌sp。囊肿被鉴定为具有不规则，双色（半乳），深蓝紫色和白色外观。成熟的Colpodella sp。囊肿被染成深红色蓝色，并在四向有丝分裂中被鉴定出来，而在双旋或单性（ATCC 30905）培养物中的B. caudatus囊肿的外观为球形和红粉色。