Rabbit anti-Human CD28 Monoclonal Antibody for Flow Cytometry and T Cell Stimulation - P10747

Core Product Specifications and Parameters

Biological Background: CD28 Function and Localization

• CD28 (T-cell-specific surface glycoprotein CD28, also known as Tp44) is a member of the immunoglobulin superfamily and functions as a costimulatory receptor essential for T-cell activation, proliferation, and survival.
• Engagement of CD28 by its ligands CD80 (B7-1) or CD86 (B7-2) provides a critical second signal that amplifies T-cell receptor (TCR) signaling, leading to enhanced interleukin-2 (IL-2) production and T-cell expansion. Related references: PMID:1650475, PMID:12196291, PMID:35397202
• CD28 signaling recruits protein kinase C-theta (PRKCQ) and the adaptor GRB2, activating NF-κB via PI3K/Akt-dependent and independent pathways to modulate gene expression in T-cells. Related references: PMID:24665965, PMID:21964608, PMID:7568038
• In conjunction with TCR/CD3 and CD40L costimulation, CD28 enhances the production of Th2 cytokines IL-4 and IL-10, contributing to humoral immune responses. Related references: PMID:8617933
• CD28 synergizes with CD40L to activate NF-κB and downstream kinases MAPK8 and PAK2, further diversifying T-cell effector functions. Related references: PMID:15067037
• CD28 is predominantly expressed on the cell surface of T-cells and plasma cells, but is absent from less mature B-cells.
• The CD28 protein is a transmembrane glycoprotein with an extracellular immunoglobulin-like domain, a single transmembrane helix, and a cytoplasmic tail containing signaling motifs. Post‑translational modifications include disulfide bonds, glycosylation, and phosphorylation.
• Alternative splicing generates multiple CD28 isoforms, which may fine‑tune co‑stimulatory signals in different T‑cell subsets.

Experimental Guidance and Technical Tips

• The immunogen, recombinant human CD28 protein, likely covers the extracellular domain, making the antibody suitable for detecting native cell‑surface CD28 by flow cytometry. Titrate on human T‑cell lines or PBMCs to determine the optimal working dilution.
• For in vitro T‑cell activation, use the antibody in combination with anti‑CD3 to provide costimulatory signals. Plate‑bound or cross‑linked formats may enhance clustering; pilot experiments should optimize concentration and stimulation duration.
• When using this antibody for functional blocking or depletion, pre‑incubate with recombinant CD28 protein to confirm the specificity of observed effects.
• Flow cytometry gating strategies should include live/dead discrimination and appropriate isotype controls to accurately quantify CD28 expression on T‑cell subsets.
• Validate cross‑reactivity in your experimental system; the antibody is reported to react with human CD28, but off‑target binding should be ruled out in the relevant sample context.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio streamlines IVD raw-material procurement for diagnostic manufacturers and research labs. Our anti‑CD28 monoclonal antibody exemplifies our commitment to providing high‑quality reagents for T‑cell biology and immuno‑oncology research. From optimized antibody pairs for sandwich immunoassays to bulk ancillary reagents, we accelerate development from concept to clinic.