Department of Medical Parasitology, Faculty of Medicine, Alexandria University, 2nd Floor, El Mowasah Medical and Educational Complex, Alexandria, Egypt.
Department of Medical Biochemistry, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
Acta Parasitol. 2024 Jun;69(2):1253-1266. doi: 10.1007/s11686-024-00851-w. Epub 2024 May 14.
Searching for a novel early diagnostic biomarker for toxoplasmosis, real-time-PCR was currently used to measure the serum mmu-miR-511-5p level in male Swiss-albino mice infected with either; ME49 or RH Toxoplasma gondii (T. gondii) strains.
Three mice groups were used; (GI) constituted the non-infected control group, while (GII) and (GIII) were experimentally infected with ME49 or RH strains, respectively. GII mice were orally infected using 10 or 20 ME49 cysts (ME-10 and ME-20), both were subdivided into; non-treated (ME-10-NT and ME-20-NT) and were further subdivided into; immunocompetent (ME-10-IC and ME-20-IC) [euthanized 3-days, 1, 2, 6 or 8-weeks post-infection (PI)], and immunosuppressed using two Endoxan injections (ME-10-IS and ME-20-IS) [euthanized 6- or 8-weeks PI], and spiramycin-treated (ME-10-SP and ME-20-SP) that received daily spiramycin, for one-week before euthanasia. GIII mice individually received 2500 intraperitoneal RH strain tachyzoites, then, were subdivided into; non-treated (RH-NT) [euthanized 3 or 5-days PI], and spiramycin-treated (RH-SP) that were euthanized 5 or 10-days PI (refer to the graphical abstract).
Revealed significant upregulation of mmu-miR-511-5p in GII, one-week PI, with gradually increased expression, reaching its maximum 8-weeks PI, especially in ME-20-NT group that received the higher infective dose. Immunosuppression increased the upregulation. Contrarily, treatment caused significant downregulation. GIII recorded significant upregulation 3-days PI, yet, treatment significantly decreased this expression.
Serum mmu-miR-511-5p is a sensitive biomarker for early diagnosis of ME49 and RH infection (as early as one-week and 3-days, respectively), and its expression varies according to T. gondii infective dose, duration of infection, spiramycin-treatment and host immune status.
为了寻找一种新型的弓形虫病早期诊断生物标志物，本研究采用实时 PCR 法检测雄性瑞士白化病小鼠感染 ME49 或 RH 弓形虫（T. gondii）株后的血清 mmu-miR-511-5p 水平。
使用三组小鼠；（GI）为非感染对照组，（GII）和（GIII）分别经口感染 ME49 或 RH 株。GII 小鼠分别用 10 或 20 个 ME49 包囊（ME-10 和 ME-20）进行口服感染，两者均分为未处理组（ME-10-NT 和 ME-20-NT），并进一步分为免疫功能正常组（ME-10-IC 和 ME-20-IC）[分别于感染后 3 天、1、2、6 或 8 周（PI）处死]和用两次依托泊苷注射免疫抑制组（ME-10-IS 和 ME-20-IS）[分别于 6 或 8 周 PI 处死]和螺旋霉素治疗组（ME-10-SP 和 ME-20-SP），即在处死前一周每天接受螺旋霉素治疗。GIII 小鼠分别接受 2500 个腹腔 RH 株速殖子，然后分为未处理组（RH-NT）[分别于 PI 后 3 或 5 天处死]和螺旋霉素治疗组（RH-SP），分别于 PI 后 5 或 10 天处死（参见图表摘要）。
GII 组在一周 PI 时显著上调 mmu-miR-511-5p，表达逐渐增加，在 8 周 PI 时达到最大值，特别是在接受更高感染剂量的 ME-20-NT 组。免疫抑制增加了上调。相反，治疗导致显著下调。GIII 组在 PI 后 3 天记录到显著上调，但治疗显著降低了这种表达。
血清 mmu-miR-511-5p 是 ME49 和 RH 感染的敏感生物标志物（分别早在一周和三天），其表达根据 T. gondii 感染剂量、感染持续时间、螺旋霉素治疗和宿主免疫状态而变化。
