Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
Department of Mathematics, Washington State University, Pullman, WA, USA.
BMC Res Notes. 2022 Feb 14;15(1):50. doi: 10.1186/s13104-022-05933-4.
The efficacy of Rhodococcus equi-specific hyperimmune plasma (HIP) is usually evaluated in vitro. Anticoagulants (AC) used for plasma collection can negatively impact bacterial replication but their effect on R. equi growth has not been evaluated. The aim of this study was to establish the effect that AC routinely used in veterinary medicine (ACD, KEDTA, Li Heparin, and Na Citrate) have on in vitro R. equi growth. To assess this, in vitro assays commonly used to test HIP efficacy (direct effect on microorganism and macrophage infection), were performed using each AC and non-treated bacteria.
There was no direct effect of ACD, Li Heparin or Na Citrate on R. equi growth. These AC significantly (p < 0.05) delayed growth for 12 h following opsonization. The number of R. equi colonies after macrophage infection was significantly (p < 0.05) lower 72 h post-opsonization with Na Citrate. KEDTA inhibited the formation of R. equi colonies by 12 h in all the assays. In conclusion, AC should be taken into consideration when interpreting in vitro results as their negative effect on bacterial growth may be mistakenly interpreted as HIP efficacy. ACD and Li Heparin appear more appropriate for the selected assays.
罗得西亚放线菌特异性高免血浆(HIP)的疗效通常在体外进行评估。用于血浆采集的抗凝剂(AC)可能会对细菌复制产生负面影响,但它们对罗得西亚放线菌生长的影响尚未得到评估。本研究的目的是确定兽医中常规使用的 AC(ACD、KEDTA、Li 肝素和 Na 柠檬酸盐)对体外罗得西亚放线菌生长的影响。为此,使用每种 AC 和未经处理的细菌进行了常用于测试 HIP 疗效的体外检测(对微生物和巨噬细胞感染的直接影响)。
ACD、Li 肝素或 Na 柠檬酸盐对罗得西亚放线菌的生长没有直接影响。这些 AC 在调理后 12 小时显著(p<0.05)延迟了生长。用 Na 柠檬酸盐调理后 72 小时,巨噬细胞感染后的罗得西亚放线菌菌落数显著(p<0.05)降低。KEDTA 在所有检测中在 12 小时内抑制了罗得西亚放线菌菌落的形成。结论:在解释体外结果时应考虑 AC,因为它们对细菌生长的负面影响可能被错误地解释为 HIP 疗效。ACD 和 Li 肝素似乎更适合所选的检测。