Quantitation of CD36 (platelet glycoprotein IV) expression on platelets and monocytes by flow cytometry: application to the study of Plasmodium falciparum malaria.
BACKGROUND
The expression of CD36 (platelet glycoprotein IV) is variable among different individuals and cannot be determined by gene analysis. Previous studies suggest that CD36 expression plays a central role in the pathophysiology of Plasmodium falciparum malaria, a disease of global significance.


METHODS
We developed a flow cytometric method to quantitatively measure CD36 on monocytes and platelets from whole blood using antibodies to CD36, CD14, and CD61 directly conjugated to different fluorochromes. Commercially available fluorescent beads were used to quantify CD36 expression.


RESULTS
The assay was successfully run at three different centers. African-Americans (n = 57), nonAfrican-Americans (n = 33), individuals with and without hemoglobin S (n = 15 and n = 12), and children with P falciparum malaria (n = 97) were tested. Platelet-monocyte aggregates, present to varying degrees in different anticoagulants, were eliminated from final analysis. The median fluorescence intensity (MFI) of CD36 among different subjects followed a log-normal distribution. Among African-Americans, 5% were CD36-deficient (logMFI < 1.5; MFI < 32). Expression of platelet CD36 paralleled monocyte CD36.


CONCLUSIONS
Flow cytometry can be used to quantify the expression of CD36 of platelets and monocytes in EDTA whole blood. The assay will allow investigation of the relationship between CD36 and clinical outcome in malaria and other disease states.
Cserti-Gazdewich
Christine M
CM
University Health Network, Toronto, Ontario, Canada. Christine.Cserti@uhn.on.ca
Dzik
Walter H
WH
Dorn
Michelle E
ME
Quagliaroli
Robert O
RO
Xu
Songyi
S
Ssewanyana
Isaac
I
Nayyar
Rakesh
R
Preffer
Frederic I
FI
D000328:Adult; D000906:Antibodies; D000918:Antibody Specificity; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism*; D018955:CD36 Antigens / Q000032:analysis* / Q000276:immunology / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D005455:Fluorescent Antibody Technique / Q000379:methods; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000097:blood* / Q000175:diagnosis; D008297:Male; D009000:Monocytes / Q000378:metabolism*; D011237:Predictive Value of Tests
D000906:Antibodies; D015415:Biomarkers; D018955:CD36 Antigens