eat-2 Antibody

Definition and Target Antigen

The Eat-2 antibody specifically binds to CD81 (also known as TAPA-1), a 26 kDa transmembrane protein expressed on B cells, T cells, NK cells, macrophages, and dendritic cells . CD81 plays roles in:

• Homotypic adhesion between B and T cells.

• Costimulation of T cell activation.

• Reproductive functions (e.g., oocyte-sperm fusion in rodents) .

Species Reactivity:

Applications of the Eat-2 Antibody

The antibody is validated for multiple experimental techniques:

Functional Effects:

• B Cell Aggregation: The Eat-2 antibody induces clustering of B cells, likely mimicking CD81-mediated adhesion .

• Inhibition of Proliferation: Blocks B cell responses to anti-Ig antibodies and IL-4 .

Research Context: EAT-2 (SH2D1B) Adaptor Protein

While distinct from the Eat-2 antibody, the EAT-2 adaptor protein (encoded by SH2D1B) shares nomenclature and is critical in immune signaling. This section contextualizes its role to avoid ambiguity.

Mechanism of Action

EAT-2 interacts with SLAM family receptors (e.g., CD150, 2B4) via its SH2 domain, amplifying pro-inflammatory and cytolytic signals in NK cells and innate immune cells . Key functions include:

1. NK Cell Activation: Enhances cytotoxic granule polarization and exocytosis toward hematopoietic targets .

2. Cytokine/Chemokine Modulation: Overexpression boosts IL-1β, IFN-γ, and TNF-α production in human PBMCs .

3. Cross-Talk with SAP: Cooperates with SAP (SH2D1A) to regulate conjugate formation and cytotoxicity .

Comparison with SAP:

EAT-2 Adaptor Protein

• Vaccine Adjuvants: Overexpression enhances DC maturation, monocyte phagocytosis, and antigen presentation, suggesting utility in vaccine design .

• Cancer Immunotherapy: Augments NK cell-mediated killing of tumor cells (e.g., K562) .

Eat-2 Antibody

• Diagnostic Probes: Enables quantification of CD81 expression in immune cells.

• Functional Studies: Tools for dissecting CD81’s role in immune adhesion and fertility .

Critical Considerations and Limitations

1. Antibody Specificity:

   • The Eat-2 clone requires both extracellular loops of CD81 for binding .

   • Cross-reactivity with rat CD81 is reported but not human .

2. EAT-2 vs. Eat-2:

   • EAT-2 (protein): Mediates SLAM receptor signaling.

   • Eat-2 (antibody): Targets CD81. Confusion may arise in literature.

Future Directions

• EAT-2 Adaptor: Investigating inflammasome activation (e.g., NLRP3, AIM2) downstream of EAT-2 overexpression .

• Eat-2 Antibody: Expanding applications to human studies for CD81 modulation in autoimmune or reproductive disorders.

References

1. PMC3978279 (EAT-2’s role in NK cell activation) .

2. PMC4055832 (EAT-2 overexpression in innate immunity) .

3. PubMed24374770 (EAT-2 in human immune responses) .

4. Thermofisher (Eat-2 antibody specifications) .

5. Antibodies.com (Eat-2 functional studies) .