Advances in understanding red blood cell modifications by Babesia

Hakimi, Hassan; Yamagishi, Junya; Kawazu, Shin-ichiro; Asada, Masahito

doi:10.1371/journal.ppat.1010770

“…Primarily, B. microti invades mature erythrocytes in mice. During invasion, Babesia secrete numerous proteins to support their development and to modify erythrocytes (Hakimi et al, 2022). Adhesive properties and permeability of infected erythrocytes are altered while cell volumes are increased (Park et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

Enhanced phosphatidylserine exposure and erythropoiesis in Babesia microti-infected mice

Song

¹

,

Cai²,

Chen³

et al. 2023

View full text Add to dashboard Cite

IntroductionBabesia microti (B. microti) is the dominant species responsible for human babesiosis, which is associated with severe hemolytic anemia and splenomegaly because it infects mammalian erythrocytes. The actual prevalence of B. microti is thought to have been substantially underestimated.MethodsIn this study, Bagg’s albino/c (BALB/c) mice were intraperitoneally injected with B. microti-infected erythrocytes, and parasitemia was subsequently measured by calculating the proportion of infected erythrocytes. The ultrastructure of infected erythrocytes was observed using scanning and transmission electron microscopes. Quantifying phosphatidylserine (PS) exposure, oxidative stress, intracellular Ca2+, and erythropoiesis of erythrocytes were done using flow cytometry. The physiological indicators were analyzed using a Mindray BC-5000 Vet automatic hematology analyzer.ResultsOf note, 40.7 ± 5.9% of erythrocytes changed their structure and shrunk in the B. microti-infected group. The percentage of annexin V-positive erythrocytes and the levels of reactive oxygen species (ROS) in the erythrocytes were higher in the B. microti-infected group than in the control group at 10 dpi. Significant splenomegaly and severe anemia were also observed following B. microti infection. The parasitemia level in the B. microti-infected splenectomized group was higher than that of the B. microti-infected sham group. The population of early erythroblasts increased, and the late erythroblasts decreased in both the bone marrow and spleen tissues of the B. microti-infected group at 10 dpi.DiscussionPS exposure and elevated ROS activities were hallmarks of eryptosis in the B. microti-infected group. This study revealed for the first time that B. microti could also induce eryptosis. At the higher parasitemia phase, the occurrence of severe anemia and significant changes in the abundance of erythroblasts in B. microti-infected mice group were established. The spleen plays a critical protective role in controlling B. microti infection and preventing anemia. B. microti infection could cause a massive loss of late erythroblasts and induce erythropoiesis.

show abstract

“…Primarily, B. microti invades mature erythrocytes in mice. During invasion, Babesia secrete numerous proteins to support their development and to modify erythrocytes ( Hakimi et al, 2022 ). Adhesive properties and permeability of infected erythrocytes are altered while cell volumes are increased ( Park et al, 2015 ).…”

Section: Introductionmentioning

confidence: 99%

Enhanced phosphatidylserine exposure and erythropoiesis in Babesia microti-infected mice

Song

¹

,

Cai

²

,

Chen

³

et al. 2023

Front. Microbiol.

0

1

View full text Add to dashboard Cite

IntroductionBabesia microti (B. microti) is the dominant species responsible for human babesiosis, which is associated with severe hemolytic anemia and splenomegaly because it infects mammalian erythrocytes. The actual prevalence of B. microti is thought to have been substantially underestimated.MethodsIn this study, Bagg’s albino/c (BALB/c) mice were intraperitoneally injected with B. microti-infected erythrocytes, and parasitemia was subsequently measured by calculating the proportion of infected erythrocytes. The ultrastructure of infected erythrocytes was observed using scanning and transmission electron microscopes. Quantifying phosphatidylserine (PS) exposure, oxidative stress, intracellular Ca2+, and erythropoiesis of erythrocytes were done using flow cytometry. The physiological indicators were analyzed using a Mindray BC-5000 Vet automatic hematology analyzer.ResultsOf note, 40.7 ± 5.9% of erythrocytes changed their structure and shrunk in the B. microti-infected group. The percentage of annexin V-positive erythrocytes and the levels of reactive oxygen species (ROS) in the erythrocytes were higher in the B. microti-infected group than in the control group at 10 dpi. Significant splenomegaly and severe anemia were also observed following B. microti infection. The parasitemia level in the B. microti-infected splenectomized group was higher than that of the B. microti-infected sham group. The population of early erythroblasts increased, and the late erythroblasts decreased in both the bone marrow and spleen tissues of the B. microti-infected group at 10 dpi.DiscussionPS exposure and elevated ROS activities were hallmarks of eryptosis in the B. microti-infected group. This study revealed for the first time that B. microti could also induce eryptosis. At the higher parasitemia phase, the occurrence of severe anemia and significant changes in the abundance of erythroblasts in B. microti-infected mice group were established. The spleen plays a critical protective role in controlling B. microti infection and preventing anemia. B. microti infection could cause a massive loss of late erythroblasts and induce erythropoiesis.

show abstract

“…Given the difficulty of sampling all phases of development equally well in vivo , and the variable developmental rhythms observed across pathogenic organisms (reviewed in [13]), these challenges likely arise in diverse systems. Like malaria parasites, Babesia parasites multiply in the blood and tend to sequester as development progresses (reviewed in [14]). The blood-borne livestock parasite Trypanosoma congolense can also sequester by binding to the blood vessel epithelium for hours at a time [15] and, as with malaria parasites, has been reported to undergo periodic oscillations in detectable abundance in mice [16].…”

Section: Introductionmentioning

confidence: 99%

Developmental synchrony and extraordinary multiplication rates in pathogenic organisms

Greischar,

Childs

2024

Preprint

0

View full text Add to dashboard Cite

The multiplication rates of pathogenic organisms influence disease progression, efficacy of immunity and therapeutics, and potential for within-host evolution. Thus, accurate estimates of multiplication rates are essential for biological understanding. We recently showed that common methods for inferring multiplication rates from malaria infection data substantially overestimate true values (i.e., under simulated scenarios), providing context for extraordinarily large estimates in human malaria parasites. A key unknown is whether this bias arises specifically from malaria parasite biology or represents a broader concern. Here we identify the potential for biased multiplication rate estimates across pathogenic organisms with different developmental biology by generalizing a within-host malaria model. We find that diverse patterns of developmental sampling bias—the change in detectability over developmental age—reliably generate overestimates of the fold change in abundance, obscuring not just true growth rates but potentially even whether populations are expanding or declining. This pattern emerges whenever synchrony, the degree to which development is synchronized across the population of pathogenic organisms comprising an infection, decays with time. Only with simulated increases in synchrony do we find noticeable underestimates of multiplication rates. Obtaining robust estimates of multiplication rates may require accounting for diverse patterns of synchrony in pathogenic organisms.Subjectscomputational biology, theoretical biology, ecology, developmental biology

show abstract

Advances in understanding red blood cell modifications by Babesia

Cited by 13 publications

References 84 publications

Enhanced phosphatidylserine exposure and erythropoiesis in Babesia microti-infected mice

Enhanced phosphatidylserine exposure and erythropoiesis in Babesia microti-infected mice

Enhanced phosphatidylserine exposure and erythropoiesis in Babesia microti-infected mice

Developmental synchrony and extraordinary multiplication rates in pathogenic organisms

Contact Info

Product

Resources

About