Molecular characterization of Schellackia parasites in an urban population of sand lizards (Lacerta agilis) from Berlin, Germany.

Lizards are hosts of several taxa of unicellular parasites of the phylum Apicomplexa, including Karyolysus, Schellackia, Lankesterella, and Hepatozoon. Parasite prevalence and the impact of infections on lizard biology remain largely unexplored. In this study, blood parasite infections were investigated in sand lizards (Lacerta agilis) from Berlin, Germany. Eighty-three individuals were investigated, and the detected blood parasites were identified as Schellackia sp. The combination of microscopic and molecular screening revealed a prevalence of 14.5%. Parasitemia values were low and most infections were subpatent. Phylogenetic analysis recovered a close relationship of the Schellackia parasites of this study with Schellackia sp. parasites of different Lacerta and Podarcis lizard species from Spain. Monitoring of Schellackia parasite infections in free-ranging lizards contributes to a better understanding of the distribution, diversity, and phylogenetic relationships of the neglected parasite taxon.

The acid ceramidase/ceramide axis controls parasitemia in Plasmodium yoelii-infected mice by regulating erythropoiesis.

Acid ceramidase (Ac) is part of the sphingolipid metabolism and responsible for the degradation of ceramide. As bioactive molecule, ceramide is involved in the regulation of many cellular processes. However, the impact of cell-intrinsic Ac activity and ceramide on the course of Plasmodium infection remains elusive. Here, we use Ac-deficient mice with ubiquitously increased ceramide levels to elucidate the role of endogenous Ac activity in a murine malaria model. Interestingly, ablation of Ac leads to alleviated parasitemia associated with decreased T cell responses in the early phase of Plasmodium yoelii infection. Mechanistically, we identified dysregulated erythropoiesis with reduced numbers of reticulocytes, the preferred host cells of P. yoelii, in Ac-deficient mice. Furthermore, we demonstrate that administration of the Ac inhibitor carmofur to wildtype mice has similar effects on P. yoelii infection and erythropoiesis. Notably, therapeutic carmofur treatment after manifestation of P. yoelii infection is efficient in reducing parasitemia. Hence, our results provide evidence for the involvement of Ac and ceramide in controlling P. yoelii infection by regulating red blood cell development.