Title: CELL MEMBRANE MICROPARTICLES IN BLOOD AND BLOOD PRODUCTS: POTENTIALLY PATHOGENIC AGENTS AND BIOMARKE
1CELL MEMBRANE MICROPARTICLES IN BLOOD AND BLOOD
PRODUCTS POTENTIALLY PATHOGENIC AGENTS AND
BIOMARKERSJAN SIMAK, Ph.D. Laboratory of
Cellular Hematology, DH/OBRR, CBER FDA
2Cell Membrane Microparticles (MPs)
- Phospholipid vesicles of 0.05 1.5 ?m in size
shed from the plasma membrane of eukaryotic
cells - Contain membrane phospholipids and express
antigens characteristic of their cell of origin - Derived from PLTs, RBCs,WBCs, ECs, and some other
cell types, circulate in blood - Specific MP phenotypes are elevated in blood in
different pathologies -
3Potentially Pathogenic Activities of MPsfor
review Simak J Gelderman MP, Transf Med Rev
2006
- Intercellular transfer of membrane proteins and
lipids - Prothrombotic effects
- Proinflammatory effects
- Impairment of endothelial function
- Modulation of vascular tone
- Induction of angiogenesis and enhancement of
cancer cells metastasis - Biologically active molecules in plasma
Soluble or MP-associated ?
4FDA/CBER Mission Relevance
- MPs as biomarkers
- QC in vitro testing of blood products and
transfusion devices - In vivo testing of adverse effects of biologics,
devices and drugs - Diagnosis of vascular, hematologic, and other
diseases - Potentially pathogenic activities of MPs in blood
products - Transfusion adverse events
5MP Research Program
Selection of MP phenotypes Flow cytometric
analysis of MP surface antigens
In Vitro Studies
Development of MP assays and investigation of
pathogenic or diagnostic importance of selected
MP phenotypes
Clinical Studies
Analysis of MPs in cellular blood products
Testing of biologics, drugs and devices
6Flow Cytometric Analysis of MPs in Plasma Simak J
et al., British J Haematol, 2004
CD105 (EC)
CD105 (EC)
CD41(PLT)
CD45 (WBC)
IgG IC
CD41 (PLT)
IgG IC
CD45 (WBC)
7MP Analysis in Vascular Diseases
- Circulating MPs in PNH and SCD (study with NHLBI)
- Hemolytic diseases with vascular injury to mimic
transfusion adverse events - MPs derived from PLTs, RBCs, WBCs, and ECs found
elevated in SCD - Endothelial MPs found elevated in both SCD and
PNH - Identified specific endothelial MP phenotypes
with potential diagnostic importance for severity
and character of vascular injury - Simak J et al., British J Haematol, 2004
8MP Analysis in Vascular Diseases II
- Circulating MPs in acute ischemic stroke (study
with NINDS) - Quantitative evaluation of vascular injury
Ischemic lesion volume measured by DWI-MRI - Specific endothelial MP phenotype correlated
with brain lesion volume - Different endothelial MP phenotype in admission
samples correlated with clinical outcome - Simak J et al., J Thromb Haemost, 2006 (in
press)
9MP Analysis in Apheresis Platelets
(APs) Gelderman MP et al., ASH 2005
- MPs derived from PLTs, WBCs, RBCs, and ECs, were
elevated in APs compared to normal plasma - TFMPs and MP-associated TF activity (FX
activation) were elevated in APs compared to
normal plasma - AP storage 5 vs 7 days No MP increase with
exception of WBC MPs including TF WBC MPs
(CD142CD45). - Effects of Washed MPs from APs on HUVEC Culture
- Increase expression of ICAM-1 and TF on cells
- G1 arrest and cell apoptosis
- Extracellular calcium influx (in PC12 cells)
10Future Plans Investigation of TFMPs in APs
Possible origin of TFMP in APs
APHERESIS STORAGE
MONOCYTE
TF
TF
CD41
TF
PSGL-1
TF
P-SEL
TF
PLT
PLT
PLT
PLT
Plt
ACTIVATION
RESTING
ACTIVATION
Modifed in vivo mechanism proposed in B. Furie
lab (Throm. Haemost. 2004)
11Future Plans, cont.
- Study of MPs in APs and red blood cell
transfusion products - Association of different MP phenotypes with in
vitro proinflammatory and proapoptotic effects of
MPs - Effects of donor characteristics, collection
devices, leukofiltration, pathogen reduction
treatments, and storage, on MP content in
cellular blood products - Design of clinical study protocols Association
of different MP phenotypes in cellular blood
products with transfusion adverse events. - FDA Collaborative project To study the
interaction of - nanomaterials with plasma membrane of blood and
- endothelial cells
-
12ACKNOWLEDGEMENTS
NHLBI Neal S. Young, MD, PhD Antonio M. Risitano,
MD, PhD NINDS Alison E. Baird, FRACP, PhD Hua Yu,
MD Violet Wright, RN, DNSc NIH CC Department of
Transfusion Medicine USUHS Olga Simakova, MS
CBER Monique P. Gelderman, PhD Karel Holada,
PhD Jaroslav Novak, PhD Jan Zivny, MD, PhD Laura
B. Carter, MT Jaroslav G. Vostal, MD, PhD