≡

Active Cluster Of Differentiation 28 (CD28)

Tp44; T-Cell-Specific Surface Glycoprotein

ACTIVITY TEST

The cluster of differentiation (CD) antigen CD28 is a central co-stimulatory molecule for TCR-mediated activation such as cytokine production and T-cell proliferation upon ligand binding and TCR stimulation. It is a member of the immunoglobulin subfamily, other members of the subfamily include ICOS, CTLA4, PD1, PD1H, TIGIT and BTLA. Cytotoxic T-Lymphocyte Associated Antigen 4 (CTLA4) and CD28 are highly homologous and compete for the same ligands, CTLA4 can also bind with CD28 to form a dimer. Thus a functional binding ELISA assay was conducted to detect the interaction of recombinant mouse CD28 and recombinant rat CTLA4. Briefly, rmCD28 was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to CTLA4-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-CD28 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 µL stop solution to the wells and read at 450/630 nm immediately. The binding activity of recombinant mouse CD28 and recombinant rat CTLA4 was shown in Figure 1, the EC50 for this effect is 2.82 ug/mL.

USAGE

Reconstitute in 10mM PBS (pH7.4) to a concentration of 0.1-1.0 mg/mL. Do not vortex.

STORAGE

Avoid repeated freeze/thaw cycles. Store at 2-8°C for one month. Aliquot and store at -80°C for 12 months.

STABILITY

The thermal stability is described by the loss rate. The loss rate was determined by accelerated thermal degradation test, that is, incubate the protein at 37°C for 48h, and no obvious degradation and precipitation were observed. The loss rate is less than 5% within the expiration date under appropriate storage condition.

GIVEAWAYS

INCREMENT SERVICES

Catalog No. Related products for research use of Mus musculus (Mouse) Organism species Applications (RESEARCH USE ONLY!)
RPA652Mu02 Recombinant Cluster Of Differentiation 28 (CD28) Positive Control; Immunogen; SDS-PAGE; WB.
RPA652Mu01 Recombinant Cluster Of Differentiation 28 (CD28) Positive Control; Immunogen; SDS-PAGE; WB.
APA652Mu01 Active Cluster Of Differentiation 28 (CD28) Cell culture; Activity Assays.
PAA652Mu02 Polyclonal Antibody to Cluster Of Differentiation 28 (CD28) WB; IHC; ICC; IP.
PAA652Mu01 Polyclonal Antibody to Cluster Of Differentiation 28 (CD28) WB; IHC; ICC; IP.