Matamoros-Suárez Raúl, Montenegro Víctor M, Villalobos-Brenes Federico, Llaberia-Robledillo Mar, Solano-Barquero Alberto, Baneth Gad, Balbuena Juan Antonio, Rojas Alicia
Laboratorio de Helmintología, Facultad de Microbiología, University of Costa Rica, San José, Costa Rica.
Posgrado Regional en Ciencias Veterinarias Tropicales, School of Veterinary Medicine, National University of Costa Rica, Heredia, Costa Rica.
Parasit Vectors. 2025 Jul 23;18(1):293. doi: 10.1186/s13071-025-06870-4.
Hepatozoon spp. are apicomplexan parasites with a heteroxenous life cycles, involving vertebrate intermediate hosts and invertebrate definitive hosts. These parasites infect a wide variety of wild and domestic vertebrates causing subclinical infection or mild-to-severe clinical manifestations, depending on the parasite species and vertebrate host. Interestingly, each Hepatozoon spp. have a specific host range, suggesting a close host-parasite coevolutionary relationship.
Hepatozoon sequences deposited between 2013 and 2023 were mined from GenBank to test which was the most employed marker for this parasite. We reconstructed the host and parasite phylogenies using 18S rDNA and cytB sequences, respectively. Subsequent analyses were stratified according to host vertebrate orders (Carnivora, Rodentia, and Squamata), and the corresponding sequences of their Hepatozoon parasites. Then, Procrustean Approach to Cophylogeny (PACo) and ParaFit were employed to assess their global cophylogenetic relationships. In addition, eMPRess was used to estimate the most probable co-evolutionary events, such as host switch, duplication, sorting, or cospeciation, accounting for the shared evolutionary history of Hepatozoon spp. and their vertebrate hosts.
Global assessments of congruence between phylogenies of carnivore, rodent, and squamate hosts and those of their Hepatozoon parasites were significant (PACo: all m < 0.655, all P < 0.001; ParaFit: all ParaFitGlobal Statistics < 72.992, all P < 0.007, all Procrustes R > 0.25), but not for the association between Hepatozoon spp. and invertebrates (PACo m = 0.632, P < 0.001; ParaFitGlobal Statistic = 8.810, P = 0.124, R = 0.37). The most significant links occurred between Hepatozoon felis and felid hosts or Hepatozoon canis and canid hosts, but not between Hepatozoon americanum and domestic dogs or coyotes. Moreover, eMPRess showed that the coevolutionary history between Hepatozoon spp. and vertebrate host phylogenies was mainly explained by host switching and less frequently by cospeciation events.
These findings highlight the ability of Hepatozoon spp. associated to certain vertebrate orders to infect those with a close phylogenetic relationship. This in turn helps to understand how hepatozoonosis can emerge in susceptible hosts within specific geographical areas by spillover events.
肝簇虫属是具有异源生命周期的顶复门寄生虫，涉及脊椎动物中间宿主和无脊椎动物终末宿主。这些寄生虫感染多种野生和家养脊椎动物，根据寄生虫种类和脊椎动物宿主的不同，可导致亚临床感染或轻度至重度的临床表现。有趣的是，每种肝簇虫属都有特定的宿主范围，这表明宿主与寄生虫之间存在密切的协同进化关系。
从GenBank中挖掘2013年至2023年间保存的肝簇虫序列，以测试哪种是该寄生虫最常用的标记。我们分别使用18S rDNA和细胞色素b序列重建宿主和寄生虫的系统发育树。随后的分析根据宿主脊椎动物目（食肉目、啮齿目和有鳞目）及其肝簇虫寄生虫的相应序列进行分层。然后，采用共系统发育的普罗克汝斯忒斯方法（PACo）和ParaFit来评估它们的整体共系统发育关系。此外，使用eMPRess来估计最可能的协同进化事件，如宿主转换、复制、分选或共物种形成，以解释肝簇虫属及其脊椎动物宿主的共同进化历史。
食肉目、啮齿目和有鳞目宿主与其肝簇虫寄生虫的系统发育之间的整体一致性评估具有显著性（PACo：所有m < 0.655，所有P < 0.001；ParaFit：所有ParaFit全局统计量 < 72.992，所有P < 0.007，所有普罗克汝斯忒斯R > 0.25），但肝簇虫属与无脊椎动物之间的关联不显著（PACo m = 0.632，P < 0.001；ParaFit全局统计量 = 8.810，P = 0.124，R = 0.37）。最显著的联系发生在猫肝簇虫与猫科宿主之间或犬肝簇虫与犬科宿主之间，而美洲肝簇虫与家犬或郊狼之间则没有。此外，eMPRess表明，肝簇虫属与脊椎动物宿主系统发育之间的协同进化历史主要由宿主转换来解释，共物种形成事件的频率较低。
这些发现突出了与某些脊椎动物目相关的肝簇虫属感染具有密切系统发育关系的动物的能力。这反过来有助于理解肝簇虫病如何通过溢出事件在特定地理区域内的易感宿主中出现。
