adipocytes, whereas S100A1 (previously S100A/S100) is most abundant in cardio-myocytes, slow twitch skeletal
muscle cells, salivary epithelial cells, and renal cells.
Additionally, S100B is found in tumour cells and subpopulations of neurons, while S100A1 has also been detected in
hippocampal neurons. S100A6 is expressed by fibroblasts
and smooth and heart muscle cells (5).
Members of the S100 family have been implicated in the Ca2+-dependent regulation of a variety of intracellular
activities, e.g. protein phosphorylation, cell proliferation (including
neoplastic transformation), and differentiation (7).
Reagent provided
Purified immunoglobulin fraction of rabbit antiserum provided in liquid form. In 0.1 mol/L NaCl, 15 mmol/L NaN3, pH
7.2.
Protein concentration g/L: See label on vial.
The antibody titre variation between different lots is less than 10% as measured by single radial immunodiffusion. This
is achieved by adjusting the titre of each individual lot to
match the titre of a reference preparation kept at -80 °C.
Immunogen
S100 isolated from cow brain.
Specificity
The antibody has been solid-phase absorbed with human plasma and cow serum proteins.
In crossed immunoelectrophoresis using 50 µL antibody per cm2 gel area, no reaction with 2 µL human plasma and 2 µL
cow serum is observed. The antibody shows one
distinct double peak (S100) with human and cow brain extracts. Staining: Coomassie Brilliant Blue.
In indirect ELISA, the antibody shows no reaction with human plasma and cow serum.
In Western blotting of purified human recombinant S100 proteins, the antibody labels S100B strongly, S100A1 weakly,
and S100A6 very weakly. No reaction was observed with
the other S100 proteins tested, S100A2, S100A3 and S100A4 (8).
As demonstrated by immunocytochemistry on formalin-fixed tissues, the antibody cross-reacts with the S100
equivalent protein in cat, horse, mouse, rat, and swine. Additionally
it reacts strongly with human and cow S100.
Precautions
1. For professional users.
2. This product contains sodium azide (NaN3), a chemical highly toxic in pure form. At product concentrations, though
not classified as hazardous, sodium azide may react with
lead and copper plumbing to form highly explosive build-ups of metal azides. Upon disposal, flush with large volumes of
water to prevent metal azide build-up in plumbing.
3. As with any product derived from biological sources, proper handling procedures should be used.
Storage
Store at 2-8 C. Do not use after expiration date stamped on vial. If reagents are stored under any conditions other
than those specified, the user must verify the conditions.
There are no obvious signs to indicate instability of this product. Therefore, positive and negative controls should be run
simultaneously with patient specimens. If unexpected
staining is observed which cannot be explained by variations in laboratory procedures and a problem with the antibody
is suspected, contact our Technical Services.
Specimen preparation
Paraffin sections: The antibody can be used for labelling paraffin-embedded tissue sections fixed in formalin. Heat-
induced epitope retrieval in DakoCytomation Target Retrieval
Solution, code No. S 1700, or 10 mmol/L citrate buffer, pH 6.0, is recommended. The tissue sections should not dry out
during the treatment or the following
immunocytochemical staining procedure.
Frozen sections and cell preparations: In frozen sections the highly soluble S100 molecule tends to show aberrant
distribution or elute from the tissue.
Staining procedure
Dilution: Polyclonal Rabbit Anti-S100, code No. Z 0311, may be used at a dilution of 1:400 when applied on formalin-
fixed, paraffin-embedded sections and using 20 minutes
heat-induced epitope retrieval in DakoCytomation Target Retrieval Solution, code No. S 1700, and 30 minutes
incubation at room temperature with the primary antibody.
Optimal conditions may vary depending on specimen and preparation method, and should be determined by each
individual laboratory. The recommended negative control is
DakoCytomation Rabbit Immunoglobulin Fraction (Solid-Phase Absorbed), code No. X 0936, diluted to the same protein
concentration as the primary antibody. Unless the
stability in the actual test system has been established, it is recommended to dilute the product immediately before use
or dilute in DakoCytomation Antibody Diluent, code No.
S 0809.
Visualization: DAKO LSAB™+/HRP kit, code No. K 0679, and DAKO EnVision™+ /HRP kits, code Nos. K 4008 and K
4010, are recommended.
Automation: The antibody is well suited for immunocytochemial staining using automated platforms, such as the
DakoCytomation Autostainer.
Performance characteristics
Cells labelled by the antibody display staining confined to the cytoplasm.
Normal tissues: Positive labelling with the antibody is observed in some Langerhans' cells and melanocytes of the skin,
interdigitating reticulum cells in lymph nodes, medullary epithelial
reticular cells in the thymus, chondrocytes in cartilagenous tissue, adipocytes in some, but not other biopsies,
myoepithelial cells in salivary glands and breast, folliculostellate cells of the
pituitary gland, and Schwann cells and glial cells of nervous tissue. Weak labelling is found in epithelial cells of the
mammary and sweat glands. A negative reaction with the antibody is