Email updates

Keep up to date with the latest news and content from Malaria Journal and BioMed Central.

Open Access Highly Accessed Research

Suppression of erythroid development in vitro by Plasmodium vivax

Tasanee Panichakul1*, Witchuda Payuhakrit2, Panyu Panburana3, Chokdee Wongborisuth4, Suradej Hongeng5 and Rachanee Udomsangpetch26

Author Affiliations

1 Faculty of Science and Technology, Suan Dusit Rajabhat University, 204/3 Sirindhorn Rd., Bangplat, Bangkok, 10700, Thailand

2 Department of Pathobiology, Faculty of Science, Mahidol University, 272 Rama VI Road, Ratchathewi District, Bangkok, 10400, Thailand

3 Department of Obstetrics and Gynaecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 272 Rama VI Road, Ratchathewi District, Bangkok, 10400, Thailand

4 Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 272 Rama VI Road, Ratchathewi District, Bangkok, 10400, Thailand

5 Department of Pediatric, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 272 Rama VI Road, Ratchathewi District, Bangkok, 10400, Thailand

6 Center for Emerging and Neglected Infectious Diseases, Mahidol University, 999 999 Phuttamonthon 4 Road, Salaya, Nakhon Pathom, 73170, Thailand

For all author emails, please log on.

Malaria Journal 2012, 11:173  doi:10.1186/1475-2875-11-173

Published: 24 May 2012

Abstract

Background

Severe anaemia due to dyserythropoiesis has been documented in patients infected with Plasmodium vivax, however the mechanism responsible for anaemia in vivax malaria is poorly understood. In order to better understand the role of P. vivax infection in anaemia the inhibition of erythropoiesis using haematopoietic stem cells was investigated.

Methods

Haematopoietic stem cells/CD34+ cells, isolated from normal human cord blood were used to generate growing erythroid cells. Exposure of CD34+ cells and growing erythroid cells to P. vivax parasites either from intact or lysed infected erythrocytes (IE) was examined for the effect on inhibition of cell development compared with untreated controls.

Results

Both lysed and intact infected erythrocytes significantly inhibited erythroid growth. The reduction of erythroid growth did not differ significantly between exposure to intact and lysed IE and the mean growth relative to unexposed controls was 59.4 ± 5.2 for lysed IE and 57 ± 8.5% for intact IE. Interestingly, CD34+ cells/erythroid progenitor cells were susceptible to the inhibitory effect of P. vivax on cell expansion. Exposure to P. vivax also inhibited erythroid development, as determined by the reduced expression of glycophorin A (28.1%) and CD 71 (43.9%). Moreover, vivax parasites perturbed the division of erythroid cells, as measured by the Cytokinesis Block Proliferation Index, which was reduced to 1.35 ± 0.05 (P-value < 0.01) from a value of 2.08 ± 0.07 in controls. Neither TNF-a nor IFN-g was detected in the culture medium of erythroid cells treated with P. vivax, indicating that impaired erythropoiesis was independent of these cytokines.

Conclusions

This study shows for the first time that P. vivax parasites inhibit erythroid development leading to ineffective erythropoiesis and highlights the potential of P. vivax to cause severe anaemia.

Keywords:
Plasmodium vivax; Erythropoiesis; Haematopoietic stem cells; Anaemia