Department of Parasitology, Universiti Malaya (UM), Kuala Lumpur, 50603, Malaysia.
Department of Medical Microbiology, Universiti Malaya (UM), Kuala Lumpur, 50603, Malaysia.
Parasit Vectors. 2022 Sep 5;15(1):313. doi: 10.1186/s13071-022-05418-0.
Blastocystis sp. is one of the most common colonisers of the intestinal tract that demonstrate strong interaction with accompanying gut bacteria. Previously, the protozoan isolated from individuals with irritable bowel syndrome (IBS) showed altered phenotypic features suggesting that it can be triggered to become pathogenic. Previous studies reported altered gut microbiota and high prevalence of Blastocystis sp. in schizophrenia patients. However, the phenotypic characteristics of Blastocystis sp. isolated from individuals with SZ have yet to be described.
In this study, faecal samples from 50 patients with severe schizophrenia (SZ) and 100 non-schizophrenic (NS) individuals were screened for Blastocystis sp.
Positive isolates were subjected to genotypic and phenotypic characterization.
We found that 12 out of 50 (24%) SZ and 5 out of 100 (5%) NS individuals were detected Blastocystis sp. positive using both in vitro culture and PCR method with no significant association to age and gender. Out of the 15 sequenced isolates, ST3 was the most prevalent subtype (66.7%) followed by ST1 (20%) and ST6 (13.3%). The isolates from SZ individuals demonstrated significant slower growth rate (34.9 ± 15.6 h) and larger range of cell diameter (3.3-140 µm). We detected higher amoebic forms and metronidazole resistance among SZ isolates with variation in cell surface glycoprotein where 98% of cells from SZ showed consistent medium to high binding affinity (+ 2 to + 3) to Concavalin A staining compared to NS isolates that demonstrated only 76% high lectin (+ 3) binding affinity. Cysteine and serine protease levels were predominantly found among SZ isolates. We also demonstrate the presence of metalloprotease in Blastocystis sp. especially among NS isolates. Introduction of solubilised antigens from SZ isolates increased the cell proliferation of HCT116 cells by two fold when compared to NS isolates.
Our findings demonstrated Blastocystis sp. isolated from SZ individuals showed variation in phenotype specifically in morphology and drug resistance. The findings indicate that the gut environment (SZ and NS) and treatment of SZ could have influenced the phenotype of Blastocystis sp.
芽囊原虫是肠道内最常见的定植者之一，与伴随的肠道细菌有很强的相互作用。以前，从肠易激综合征（IBS）患者中分离出的原生动物表现出改变的表型特征，表明它可以被触发而成为致病性的。先前的研究报告称，精神分裂症患者的肠道微生物群发生改变，芽囊原虫的患病率较高。然而，精神分裂症患者中分离出的芽囊原虫的表型特征尚未被描述。
本研究对 50 例严重精神分裂症（SZ）患者和 100 例非精神分裂症（NS）个体的粪便样本进行了芽囊原虫筛查。
阳性分离物进行了基因型和表型特征分析。
我们发现，50 例 SZ 患者中有 12 例（24%）和 100 例 NS 个体中有 5 例（5%）通过体外培养和 PCR 方法检测到芽囊原虫阳性，与年龄和性别无显著相关性。在测序的 15 个分离物中，ST3 是最常见的亚型（66.7%），其次是 ST1（20%）和 ST6（13.3%）。SZ 个体的分离物表现出明显较慢的生长速度（34.9±15.6 h）和更大的细胞直径范围（3.3-140 μm）。我们检测到在 SZ 分离物中存在更高的阿米巴形态和甲硝唑耐药性，并且在细胞表面糖蛋白中存在变异，其中 98%的 SZ 细胞对 ConA 染色显示出一致的中到高结合亲和力（+2 到+3），而 NS 分离物仅显示 76%的高凝集素（+3）结合亲和力。半胱氨酸和丝氨酸蛋白酶水平主要存在于 SZ 分离物中。我们还证明了芽囊原虫中存在金属蛋白酶，尤其是在 NS 分离物中。与 NS 分离物相比，SZ 分离物的可溶性抗原的引入使 HCT116 细胞的细胞增殖增加了两倍。
我们的研究结果表明，从 SZ 个体中分离出的芽囊原虫在表型上表现出变化，特别是在形态和耐药性方面。研究结果表明，肠道环境（SZ 和 NS）和 SZ 的治疗可能影响了芽囊原虫的表型。
