Name: iFluor® 555 Anti-human CD21 Antibody *HI21a*
Brand: AAT Bioquest
SKU: 10210090
Availability: InStock

iFluor® 555 Anti-human CD21 Antibody

HI21a

The HI21a monoclonal antibody recognizes human CD21, a 145 kD transmembrane glycoprotein frequently expressed on the surface of thymocytes and dendritic cells. CD21 plays a role in vital cellular pathways, namely, the complement activation, classical pathway. In addition, it has been associated with vital biological processes like immune response, specifically innate immune response. From a research standpoint, it is of biological interest due to its association with essential macromolecules/ligands such as CD19, CD23 and C3d. CD21 is a fairly uncommon antibody target, with a little more than 5000 publications in the last decade. Even still, CD21 is essential for complement, innate immunity and immunology research, often serving as a phenotypic marker for differentiating cell types in flow cytometric applications. This antibody was purified through affinity chromatography and conjugated to iFluor® 555 (ex/em = 557/570 nm). It is compatible with the 561 nm laser and 577/35 nm bandpass filter (for example, as in the Luminex Amnis FlowSight).

Datasheet

SDS

COA

Catalog	Size	Price	Quantity
10210090	100 tests	Price
10210091	500 tests	Price

Conjugation

We provide custom conjugation services for this antibody (e.g. labeling of CD21 antibody with HRP). A list of available labels can be found in the table below:

Label Type	Available Labels
AF	AF350, AF488, AF555, AF594, AF647, AF680, AF700, AF750
Proteins	HRP, Alkaline Phosphatase, Streptavidin
Tandems	APC, APC/Cy7, APC/AF750, APC/iFluor™ 700, APC/iFluor™ 750, PE, PE/Cy5, PE/Cy7, PE/AF610, PE/AF700, PE/iFluor™ 594, PE/iFluor™ 647, PE/iFluor™ 700, PE/iFluor™ 750, PE/Texas Red®, PerCP, PerCP/Cy5.5
Small Molecules	Biotin
Traditional Dyes	FITC (fluorescein), TRITC, PacBlue, PacOrange, Cy3, Cy5
iFluor	350, 405, 430, 450, 488, 514, 532, 546, 555, 560, 568, 594, 610, 633, 647, 660, 670, 680, 700, 710, 750, 790, 800, 810, 820, 840, 860, A7
mFluor	UV375, UV460, Violet 450, Violet 500, Violet 510, Violet 540, Blue 570, Green 620, Red 700, Red 780

For additional information about custom conjugations, please consult our services page

here

Physical properties

Molecular weight	N/A
Solvent	water

Antibody properties

Other names	CR2, C3dR, Epstein-Barr virus receptor
Clone	HI21a
Host	Mouse
Isotype	IgG2a
Reactivity	Human
Application	Flow Cytometry (FACS), Fluorescence Imaging

Spectral properties

Correction factor (260 nm)	0.23
Correction factor (280 nm)	0.14
Extinction coefficient (cm ^-1 M ^-1)	100000 ¹
Excitation (nm)	557
Emission (nm)	570
Quantum yield	0.64 ¹

Usage and storage

Intended use	Research Use Only (RUO)
Storage	Refrigerated (2-8 °C); Minimize light exposure

Telephone
Fax
Email	sales@aatbio.com
International	See distributors
Bulk request	Inquire
Custom size	Inquire
Technical Support	Contact us
Request quotation	Request
Purchase order	Send to sales@aatbio.com
Shipping	Standard overnight for United States, inquire for international

Page updated on August 5, 2026