Detection of CD1a in MOLT‑4 Human Cell Line by Flow Cytometry. MOLT‑4 human acute lymphoblastic leukemia cell line was stained with Mouse Anti-Human CD1a Alexa Fluor® 700‑conjugated Monoclonal Antibody (Catalog # FAB7076N, filled histogram) or isotype control antibody (Catalog # IC002N, open histogram). View our protocol for Staining Membrane-associated Proteins.
Preparation and Storage
The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage
Protect from light. Do not freeze.
12 months from date of receipt, 2 to 8 °C as supplied.
CD1a (also known as Leu6) ia a 48-50 kDa member of the five gene CD1
family of molecules. It is a type I
transmembrane glycoprotein that is 311 amino acids (aa) in length. It contains three " alpha -domains" in its
extracellular region (aa 17-300), and terminates with a short six aa
segment. Although CD1a orthologs are
found in multiple mammalian species, it does not appear to exist in
rodent. Notably, not all humans possess
a functional CD1a gene. CD1a serves as
an MHC Class I type molecule that presents lipids to alpha beta TCRs on T cells. This means it exists as a heterodimer with beta 2-microglobulin
on the cell surface. CD1a is unique in
that it can present nonhydrophilic lipids to T cells; that is, there is no need
for a polar "head" on one end of the lipid to interact with the polar residues
of the TCR protein. Other cell membrane
components suggested to associate with CD1a include CD74 and CD9, two molecules
that may regulate cycling of CD1a. Cells
that are known to express CD1a are restricted in number, and include cortical
thymocytes, Langerhans cells, dermal dendritic cells (DC), and monocyte-derived
DC. It has been suggested that type I
mono-DCs, or those that secrete IL-12 and promote Th1 formation, are uniquely
CD1a+. At this time, this appears to be
too restrictive an assumption, and that the presence or absence of CD1a is only
generally reflective of function.