The role of immature neutrophils in controlling chronic Plasmodium chabaudi infection

FANG Jiaqin; LIU Taiping; XU Wenyue

doi:10.13431/j.cnki.immunol.j.20240104

Abstract：Objective The aim of this study was to investigate the effect of immature neutrophils on chronic Plasmodium chabaudi(P.c)infection.Methods Single-cell sequencing combined with flow cytometry was used to detect dynamic changes in immature neutrophils and its S100A9 protein expression during P.c infection.Mice were intragastrically administered Paquinimod to deplete the immature neutrophils.Flow cytometry was used to assess its effect on the immune response against Plasmodium chabaudi.Single-cell sequencing and flow cytometry were conducted on splenocytes to examine changes of monocytes/macrophages.Results Clodronate liposomes(CLs)were administered and parasitemia and survival rates were monitored.The data showed that the frequency and number of immature neutrophils increased significantly during the chronic phase of P.c infection.Parasitemia was significantly elevated in the drug-treatment group,accompanied by a reduction in the frequency and number of immature neutrophils and monocytes.After CLs treatment,monocytes and macrophages decreased and parasitemia increased.Conclusion Taken together,a large number of immature neutrophils are newly generated during the chronic phase of Plasmodium chabaudi infection,and they may exert an anti-Plasmodium chabaudi protective role through an impact on monocytes.