锌和甲氧苄啶联合治疗抑制流感 A 病毒在鸡胚中的感染。

Combination therapy of zinc and trimethoprim inhibits infection of influenza A virus in chick embryo.

机构信息

Mastropix Health Care, 35 Mew Walk, North Ferriby, HU14 3AH, UK.

出版信息

Virol J. 2021 Jun 3;18(1):113. doi: 10.1186/s12985-021-01585-1.

DOI:10.1186/s12985-021-01585-1

PMID:34082750

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8173514/

Abstract

BACKGROUND

Respiratory RNA viruses including influenza virus have been a cause of health and economic hardships. These viruses depend on its host for replication and infection. Influenza virus infection is lethal to the chick embryo. We examined whether a combination of trimethoprim and zinc (Tri-Z), that acts on the host, can reduce the lethal effect of influenza A virus in chick embryo model.

METHOD

Influenza virus was isolated from patients and propagated in eggs. We determined viral load that infects 50% of eggs (50% egg lethal dose, ELD). We introduced 10 ELD into embryonated eggs and repeated the experiments using 100 ELD. A mixture of zinc oxide (Zn) and trimethoprim (TMP) (weight/weight ratios ranged from 0.01 to 0.3, Zn/TMP with increment of 0.1) was tested for embryo survival of the infection (n = 12 per ratio, in triplicates). Embryo survival was determined by candling eggs daily for 7 days. Controls of Zn, TMP, saline or convalescent serum were conducted in parallel. The effect of Tri-Z on virus binding to its cell surface receptor was evaluated in a hemagglutination inhibition (HAI) assay using chicken red cells. Tri-Z was prepared to concentration of 10 mg TMP and 1.8 mg Zn per ml, then serial dilutions were made. HAI effect was expressed as scores where ++++ = no effect; 0 = complete HAI effect.

RESULTS

TMP, Zn or saline separately had no effect on embryo survival, none of the embryos survived influenza virus infection. All embryos treated with convalescent serum survived. Tri-Z, at ratio range of 0.15-0.2 (optimal ratio of 0.18) Zn/TMP, enabled embryos to survive influenza virus despite increasing viral load (> 80% survival at optimal ratio). At concentration of 15 µg/ml of optimal ratio, Tri-Z had total HAI effect (scored 0). However, at clinical concentration of 5 µg/ml, Tri-Z had partial HAI effect (+ +).

CONCLUSION

Acting on host cells, Tri-Z at optimal ratio can reduce the lethal effect of influenza A virus in chick embryo. Tri-Z has HAI effect. These findings suggest that combination of trimethoprim and zinc at optimal ratio can be provided as treatment for influenza and possibly other respiratory RNA viruses infection in man.

摘要

背景

包括流感病毒在内的呼吸道 RNA 病毒一直是造成健康和经济困难的原因。这些病毒依赖其宿主进行复制和感染。流感病毒感染对鸡胚是致命的。我们研究了一种针对宿主的药物组合（三苯氧嘧啶和锌，简称 Tri-Z）是否可以降低甲型流感病毒在鸡胚模型中的致死作用。

方法

我们从患者中分离流感病毒并在鸡蛋中繁殖。我们确定了感染 50%鸡蛋的病毒载量（半数致死剂量，ELD）。我们将 10 个 ELD 引入鸡胚，并使用 100 个 ELD 重复实验。我们测试了锌（Zn）和三苯氧嘧啶（TMP）混合物（重量/重量比从 0.01 到 0.3 不等，Zn/TMP 以 0.1 的增量递增）对感染的胚胎存活率（每组 12 个，重复 3 次）。通过每天对鸡蛋进行照蛋来确定胚胎存活情况，持续 7 天。同时进行锌、TMP、生理盐水或恢复期血清的对照实验。使用鸡红细胞在血凝抑制（HAI）测定中评估 Tri-Z 对病毒与其细胞表面受体结合的影响。将 Tri-Z 制备成每毫升含 10 毫克 TMP 和 1.8 毫克 Zn 的浓度，然后进行系列稀释。HAI 效应表示为分数，其中++++=无效应；0=完全 HAI 效应。

结果

TMP、Zn 或生理盐水单独使用对胚胎存活率没有影响，没有一个胚胎能在流感病毒感染中存活。所有用恢复期血清处理的胚胎都存活了下来。在 0.15-0.2（最佳 0.18）Zn/TMP 比例范围内的 Tri-Z，使胚胎能够在病毒载量增加的情况下存活下来（最佳比例时存活率超过 80%）。在最佳比例的 15μg/ml 浓度下，Tri-Z 具有完全的 HAI 效应（评分为 0）。然而，在 5μg/ml 的临床浓度下，Tri-Z 具有部分 HAI 效应（++）。