Anaplasma Phagocytophilum Major Surface Protein (Msp)-2 Directly Binds to Platelet Selectin Glycoprotein Ligand-1 (CD162) Prior to Cell Entry and Infection

숙주세포 침입을 위한 Anaplasma phagocytophilum의 주요 표면단백질 (Msp)-2과 PSGL-1 (CD162)과의 반응

  • Park Jin-Ho (Bio-Safety Research Institute and College of Veterinary Medicine, Chonbuk National University)
  • Published : 2006.03.01

Abstract

Anaplasma phagocytophilum major surface protein-2 (Msp2 or p44) is the immunodominant outer membrane protein of the bacterium. Recently, we disclosed that Msp2 was an A. phagocytophilum adhesin for binding to host neutrophils and HL-60 cells, probably mediated by attachment to platelet selectin glycoprotein ligand-1 (PSGL-1). In this study, we further elucidated that Msp2 bound to PSGL-1/FucT IV-transfected BJAB but not nontransfected BJAB cells. Binding of recombinant Msp2 or cell (lee bacteria to the surface of PSGL-1/FucT IV-transfected BJAB cells was significantly higher than to nontransfected BJAB cells (p<0.01 and p<0.01). Also, Msp2 monoclonal antibody and soluble recombinant Msp2 as antagonist led to concentration-dependent reductions in A. phagocytophilum adhesln (p<0.05 and p<0.01) to transfected BJAB cells. Thus, we conclude that Msp2 of. A. phagocytophilum acts as an adhesin by which the bacterium binds to PSGL-1 on host neutrophils and myeloid cells.

Anaplasma phagocytophilum의 주요 표면단백질인 Msp2 (p44)는 세균의 표면에 발현되는 주요한 항원 단백질이다. 본 실험에서는 A. phagocytophilum이 주요 숙주세포인 호중구나 HL-60 세포에 침입하는 데 있어, 세균의 주요 표면 단백질인 Msp2와 숙주세포의 표면에 발현되는 PSGL-1과의 반응 여부를 알아보았다. 그 결과, 재조합 단백질인 Msp2나 순수하게 분리된 A. phagocytophilum이 PSGL-1/FucT IV 유전자가 형질전환되어 PSGL-1이 발현되는 BJAB 세포와는 결합하지만, 순수한 BJAB 세포와는 전현 반응하지 않는 것을 관찰할 수 있었다(p<0.01 & p<0.01). 또한, 순수하게 분리된 A. phagocytophilum과 형질전환된(PSGL-1/FucT IV) BJAB 세포와의 결합이 Msp2의 단-클론항체나 Msp2 재조합 단백질의 농도에 따라 억제됨을 관찰할 수 있었다(p<0.05 & p<0.01). 따라서 A. phagocytophilum의 Msp2가 숙주세포인 호중구의 표면에 발현되는 PSGL-1과 직접적으로 결합하는 부착물질임을 알 수 있었다.

Keywords

References

  1. Asanovich KM, Bakken JS, Madigan JE, Aguero-Rosenfeld M, Wormser GP, Dumler JS. Antigenic diversity of granulocytic Ehrlichia isolates from humans in Wisconsin and New York and a horse in California. J Infect Dis 1997; 176: 1029-1034 https://doi.org/10.1086/516529
  2. Caspersen K, Park JH, Patil S, Dumler JS. Genetic variability and stability of Anaplasma phagocytophila msp2 (p44). Infect Immun 2002; 70: 1230-1234 https://doi.org/10.1128/IAI.70.3.1230-1234.2002
  3. Chen SM, Dumler JS, Bakken JS, Walker DH. Identification of a granulocytotropic Ehrlichia species as the etiologic agent of human disease. J Clin Microbiol 1994; 32: 589-595
  4. Dumler JS, Asanovich KM, Bakken JS, Richter P, Kimsey R, Madigan JE. Serologic cross-reactions among Ehrlichia equi, Ehrlichia phagocytophila, and human granulocytic Ehrlichia. J Clin Microbiol 1995; 33: 1098-1103
  5. Dumler JS, Bakken JS. Ehrlichial diseases of humans: emerging tick-borne infections. Clin Infect Dis 1995; 20: 1102-1110 https://doi.org/10.1093/clinids/20.5.1102
  6. Heimer R, VanAndel A, Wormser GP, Wilson ML. Propagation of granulocytic Ehrlichia spp. from human and equine sources in HL-60 cells induced to differentiate into functional granulocytes. J Clin Microbiol 1997; 35: 923-927
  7. Herron MJ, Nelson CM, Larson J, Snapp KR, Kansas GS, Goodman JL. Intracellular parasitism by the human granulocytic ehrlichiosis bacterium through the P-selectin ligand, PSGL-1. Science 2000; 288: 1653-1656 https://doi.org/10.1126/science.288.5471.1653
  8. IJdo JW, Sun W, Zhang Y, Magnarelli LA, Fikrig E. Cloning of the gene encoding the 44-kilodalton antigen of the agent of human granulocytic ehrlichiosis and characterization of the humoral response. Infect Immun 1998; 66: 3264-3269
  9. Goodman JL, Nelson CM, Klein MB, Hayes SF, Weston BW. Leukocyte infection by the granulocytic ehrlichiosis agent is linked to expression of a selectin ligand. J Clin Invest 1999; 103: 407-412 https://doi.org/10.1172/JCI4230
  10. Goodman JL, Nelson C, Vitale B, Madigan JE, Dumler JS, Kurtti TJ, Munderloh UG Direct cultivation of the causative agent of human granulocytic ehrlichiosis. N Engl J Med 1996; 334: 209-215 https://doi.org/10.1056/NEJM199601253340401
  11. Madigan JE, Richter PJ, Kimsey RB, Barlough JE, Bakken JS, Dumler JS. Transmission and passage in horses of the agent of human granulocytic ehrlichiosis. J Infect Dis 1995; 172: 1141-1144 https://doi.org/10.1093/infdis/172.4.1141
  12. McGarey DJ, Allred DR. Characterization of hemagglutinating components on the Anaplasma marginale initial body surface and identification of possible adhesins. infect Immun 1994; 62: 4587-4593
  13. Murphy CI, Storey JR, Recchia J, Doros-Richert LA, Gingrich-Baker C, Munroe K, Bakken JS, Coughlin RT, Beltz GA. Major antigenic proteins of the agent of human granulocytic ehrlichiosis are encoded by members of a multigene family. Infect Immun 1998; 66: 3711-3718
  14. Ogden NH, Woldehiwet Z, Hart CA. Granulocytic ehrlichiosis: an emerging or rediscovered tick-borne disease? J Med Microbiol 1998; 47: 475-482 https://doi.org/10.1099/00222615-47-6-475
  15. Snapp KR, Wagers AJ, Craig R, Stoolman LM, Kansas GS. P-selectin glycoprotein ligand-1 is essential for adhesion to P-selectin but not E-selectin in stably transfected hematopoietic cell lines. Blood 1997; 89: 896-901
  16. Vidotto MC, McGuire TC, McElwain TF, Palmer GH, Knowles DP Jr. Intermolecular relationships of major surface proteins of Anaplasma marginale. Infect Immun 1994; 62: 2940-2946
  17. Walker DH, Dumler JS. Emergence of the ehrlichioses as human health problems. Emerg Infect Dis 1996; 2: 18-29 https://doi.org/10.3201/eid0201.960102
  18. Woldehiwet Z. The effects of tick-borne fever on some functions of polymorphonuclear cells of sheep. J Comp Pathol 1987; 97: 481-485 https://doi.org/10.1016/0021-9975(87)90026-0
  19. Zhi N, Ohashi N, Rikihisa Y. Multiple p44 genes encoding major outer membrane proteins are expressed in the human granulocytic ehrlichiosis agent. J Biol Chem 1999; 274: 17828-17836 https://doi.org/10.1074/jbc.274.25.17828
  20. Zhi N, Rikihisa Y, Kim HY, Wormser GP, Horowitz HW. Comparison of major antigenic proteins of six strains of the human granulocytic ehrlichiosis agent by Western immunoblot analysis. J Clin Microbiol 1997; 35: 2606-2611