Re: PE-CY5 BINDING

Thomas Delohery (t-delohery@ski.mskcc.org)
Tue, 19 Aug 1997 12:25:39 +0530

>There is a letter to the editor in BLOOD , September 1996,
>15:88(6):23558-61 by van Vugt, MJ et al which shows that PE-CY5
>binds SPECIFICALLY to the Fc(gamma)R1 receptor (CD64). These
>experiments using mouse B cells transfected with different human Fc
>receptors showed that only FcR1 cells bound PE-CY5. Whole blood
>showed much less binding than isolated cells. Their recommendation
>was that any antibody that you are using labelled with PE-CY5 be tested
>for FcR1 binding.
>In our hands blocking with heat inactivated normal human AB serum will
>significantly reduce the Fc binding in humans.
>
>Mike Keeney
>London Health Sciences Centre
>London Ontario Canada

along the same line:

Takizawa, F. Kinet, J.P. Adamczewski, M.
D 1993

T Binding of Phycoerythrin and Its Conjugates to Murine Low Affinity
Receptors for Immunoglobulin-G

%J Journal of Immunological Methods

%C PO Box 211, 1000 AE Amsterdam, Netherlands
%I Elsevier Science Publishers BV
%V 162
%N 2
%P 269-272
%@ 0022-1759
%K Phycoerythrin; Flow Cytometry; Fc Receptor; (Mouse); FC-RECEPTORS; MACROPHAGE

%X Conjugates of R-phycoerythrin are widely used for immunohistochemistry,
especially for two-color flow cytometry. Their use is however limited by
their apparent tendency to bind non-specifically. Using cells transfected
with cDNAs for the murine low affinity receptors for immunoglobulin G
(FcgammaRII and -III) and cells naturally expressing these receptors, we
demonstrate that R-phycoerythrin and its conjugates bind specifically and
inhibitably to FcgammaRII and -III. Immunofluorescence stainings of cells
bearing these receptors, such as macrophages, monocytes, neutrophils, mast
cells, subsets of T cells, and natural killer cells, may therefore not
reflect the binding of antibody to antigen, but rather the binding of
R-phycoerythrin to the receptors.

%W M Adamczewski, Niaid, Molec Allergy & Immunol Sect, Twinbrook II, RM
108, 12441 Parklawn Dr, Rockville, MD 20852

--
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 Thomas Delohery                          |Internet: t-delohery@ski.mskcc.org
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