title: Development and evaluation of a prototype non-woven fabric filter for purification of malaria-infected blood.
abstract: BACKGROUND
  Many malaria-related studies depend on infected red blood cells (iRBCs) as fundamental material; however, infected blood samples from human or animal models include leukocytes (white blood cells or WBCs), especially difficult to separate from iRBCs in cases involving Plasmodium vivax. These host WBCs are a source of contamination in biology, immunology and molecular biology studies, requiring their removal. Non-woven fabric (NWF) has the ability to adsorb leukocytes and is already used as filtration material to deplete WBCs for blood transfusion and surgery. The present study describes the development and evaluation of a prototype NWF filter designed for purifying iRBCs from malaria-infected blood.
  
  
  METHODS
  Blood samples of P. vivax patients were processed separately by NWF filter and CF11 column methods. WBCs and RBCs were counted, parasite density, morphology and developing stage was checked by microscopy, and compared before and after treatment. The viability of filtrated P. vivax parasites was examined by in vitro short-term cultivation.
  
  
  RESULTS
  A total of 15 P. vivax-infected blood samples were treated by both NWF filter and CF11 methods. The WBC removal rate of the NWF filter method was 99.03%, significantly higher than the CF11 methods (98.41%, P < 0.01). The RBC recovery rate of the NWF filter method was 95.48%, also significantly higher than the CF11 method (87.05%, P < 0.01). Fourteen in vitro short-term culture results showed that after filter treatment, P. vivax parasite could develop as normal as CF11 method, and no obvious density, developing stage difference were fund between two methods.
  
  
  CONCLUSIONS
  NWF filter filtration removed most leukocytes from malaria-infected blood, and the recovery rate of RBCs was higher than with CF11 column method. Filtrated P. vivax parasites were morphologically normal, viable, and suitable for short-term in vitro culture. NWF filter filtration is simple, fast and robust, and is ideal for purification of malaria-infected blood.
authors.affiliation: Jiangsu Institute of Parasitic Diseases, Meiyuan Yangxiang 117, Wuxi 214064, People's Republic of China.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Tao
authors.forename: Hui
authors.initials: H
authors.lastname: Xia
authors.forename: Jun
authors.initials: J
authors.lastname: Cao
authors.forename: Qi
authors.initials: Q
authors.lastname: Gao
mesh_terms: D000328:Adult; D000818:Animals; D001769:Blood / Q000469:parasitology*; D002469:Cell Separation / Q000379:methods; D002470:Cell Survival; D004912:Erythrocytes / Q000469:parasitology*; D005374:Filtration / Q000379:methods*; D006801:Humans; D016780:Malaria, Vivax / Q000469:parasitology*; D051379:Mice; D008853:Microscopy; D010962:Plasmodium berghei / Q000166:cytology / Q000254:growth & development / Q000302:isolation & purification* / Q000502:physiology; D010966:Plasmodium vivax / Q000166:cytology / Q000254:growth & development / Q000302:isolation & purification* / Q000502:physiology