T-lymphocyte activation antigen CD86 (CD86)

CD86 target protein structure

Figure1: CD86 target protein structure.

CD86 Target Introduction

Protein Function

CD86 is a glycosylated protein of approximately 70 KDa, composed of 329 amino acids (about 37 KDa), a single transmembrane domain, and a cytoplasmic domain.
CD86 is expressed on antigen-presenting cells and serves as a ligand for two proteins on T cells, CD28 and CTLA-4 (cytotoxic T-lymphocyte-associated protein 4).
The binding of CD86 to CD28 provides a co-stimulatory signal for T cell activation, while the binding of CD86 to CTLA-4 negatively regulates T cell activation and reduces immune response.
CD86 can also participate in the regulation of B cell function and play a role in regulating the production of IgG1. The interaction between CD40 and CD86 can activate phospholipase C and protein kinase C, activating the NF-kappa-B signaling pathway.

Protein Expression

The expression of CD86 on the surface of B cells is rapidly upregulated upon activation by cross-linking with Ig receptors or under the influence of various cytokines.
The expression level of CD86 on the surface of monocytes is relatively low and can be upregulated by stimulation with interferon-gamma (IFN-γ).
CD86 is expressed on interdigitating DCs, Langerhans cells, peripheral blood dendritic cells, memory B cells, germinal center B cells, and macrophages.

Protein Localization

Cell membrane.

ICC experimental result image of CD86 protein

Figure 2: ICC experimental result image of CD86 protein, Anti-CD86 antibody [EPR21962] (ab239075). Green: CD86, Red: alpha Tubulin, Blue: DAPI.

Isoforms & Post-translational modifications

Human (P42081):
Isoforms 1, 2 (P42081-1, 3): 37.0~37.6 kDa (predicted)
Isoform 3 (P42081-2): 12.8 kDa (predicted)
Isoform 4 (P42081-4): 31.2 kDa (predicted)
Isoforms 5, 6 (P42081-5, 6): 24.7~28.4 kDa (predicted)
Mouse (P42082):
Isoforms 1, 2 (P42081-1, 2): 33.9~34.6 kDa (predicted)
Existence of glycosylation and polyubiquitination post-translational modifications.

IHC experiment tips

Precautions

Please note that the expression level of CD86 may vary in different samples. We recommend using samples with abundant immune cells for detection, such as spleen, tonsils, or some tumor tissues. Before testing, it is necessary to confirm the expression level of the target protein. We also recommend performing the experiment with the positive control suggested in the antibody product manual.

Positive control

Human tonsil tissue

Example of results

IHC experimental results of CD86 protein

Figure 3: IHC experimental results of CD86 protein, Anti-CD86 antibody [EP1158-37] (ab269587).

Sample name: Human tonsil paraffin section.
Primary antibody: diluted 100 times.
Antigen retrieval method: Heat-induced antigen retrieval, Tris-EDTA buffer (pH 9.0).

Key control points

In the experiment, special attention should be given to key control points in addition to routine issues:

Sample fixation:

The fixation time of the sample depends on the size of the tissue block and the type of tissue, but for most samples, such as fixation with 4% PFA, it is more appropriate to fix at room temperature for 18-24 hours.

Antigen retrieval:

We recommend using a pressure cooker for heat-induced antigen retrieval when performing immunohistochemistry experiments on paraffin sections. You can try fixing the sections at 110°C for 15 minutes. After retrieval, let it cool naturally; avoid putting it in cold water to prevent delamination caused by a sudden temperature drop.

Blocking:

If using HRP conjugate for detection, please use 3% hydrogen peroxide to treat the sections for 10 minutes to block endogenous peroxidase.
If using fluorescently labeled secondary antibodies for the experiment, it is recommended to use a blocking solution containing 1% BSA and a final concentration of 0.3 M glycine to quench the spontaneous fluorescence caused by aldehyde groups.