The M1/69 monoclonal antibody reacts with mouse CD24 also known as heat stable antigen (HSA), a 35-50 kDa glycosylated membrane protein. CD24 is expressed by erythrocytes, granulocytes, monocytes, lymphocytes, and dendritic cells. Immature B cells in bone marrow and spleen of adult mice express high levels of CD24, while mature peripheral B cells express intermediate levels of CD24. The expression of CD24 has been used to resolve stages of B cell lymphopoiesis in mouse bone marrow. It has been reported that P-selectin (CD62P) binds to CD24. CD24 is often overexpressed in human tumors. In cancer, CD24 is a regulator of cell migration, invasion, and proliferation.

The 6G5j monoclonal antibody reacts with an antigen epitope shared by mouse carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 1, 3, 5, 6, and 8, also known as CD66a, d, e, c, and b. CEACAMs are highly glycosylated membrane proteins belonging to the immunoglobulin superfamily. CEACAMs are involved in cell adhesion, proliferation, differentiation, apoptosis, T and B cell activation and except for CEACAM 8, they also serve as bacterial pathogen receptors. CEACAM 1 is expressed by epithelial, endothelial, and immune cells. CEACAM 3 and 8 are solely expressed in granulocytes, CEACAM 5 in epithelial cells and CEACAM 6 in epithelium and granulocytes. Antibodies against CEACAMs are commonly used in immunohistochemistry and flow cytometry to identify cells expressing the glycoprotein in tissue samples and cell culture. However, CEACAM 1, 5 and 6 are also found in serum where they can be used as tumor markers.

The 9E9 monoclonal antibody reacts with mouse CD16.2, also known as FcγRIV (Fc receptor, IgG, low affinity IV). CD16.2 is a member of the immunoglobulin superfamily and is expressed on monocytes, macrophages, dendritic cells, and neutrophils. Fcγ receptors are essential for IgG-dependent effector functions in vivo. CD16.2 requires the common Fcγ chain for expression and signaling. CD16.2 binds to IgG2a and IgG2b with intermediate affinity. IgG2a- and IgG2b-dependent effector functions are severely impaired in CD16.2 deficient mice. CD16.2 has also been reported to be a low-affinity IgE receptor for all IgE allotypes and promotes IgE-induced lung inflammation. The 9E9 antibody has been shown to inhibit cellular CD16.2 function.

The MOAB-2 monoclonal antibody (epitope mapped to residues 1-5 of human Aβ) is a pan-specific antibody. Using synthetic Aβ, it recognizes unaggregated, oligomeric or fibrillar forms of Aβ42 and unaggregated Aβ40, and is selective for human Aβ42 over Aβ40. With synthetic Aβ or human or rodent brain homogenates, MOAB-2 specifically detects Aβ, but not amyloid precursor protein (APP), which is cleaved by β- and Y- secretase to release Aβ. With immunostaining of human or rodent tissue, MOAB-2 detects intraneuronal Aβ, as well as diffuse or compact amyloid plaques.

The RMP1-14 monoclonal antibody reacts with mouse PD-1 (programmed death-1) also known as CD279. PD-1 is a 50-55 kDa cell surface receptor encoded by the Pdcd1 gene that belongs to the CD28 family of the Ig superfamily. PD-1 is transiently expressed on CD4 and CD8 thymocytes as well as activated T and B lymphocytes and myeloid cells.

The 53-6.7 monoclonal antibody reacts with mouse CD8α. The CD8 antigen is a transmembrane glycoprotein that acts as a co-receptor for the T cell receptor (TCR). Like the TCR, CD8 binds to class I MHC molecules displayed by antigen presenting cells (APC). CD8 is primarily expressed on the surface of cytotoxic T cells, but can also be found on thymocytes, natural killer cells, and some dendritic cell subsets. CD8 most commonly exists as a heterodimer composed of one CD8α and one CD8β chain however, it can also exist as a homodimer composed of two CD8α chains. Both the CD8α and CD8β chains share significant homology to immunoglobulin variable light chains. The molecular weight of each CD8 chain is approximately 34 kDa. The 53-6.7 antibody exhibits depleting activity when used in vivo.

The 145-2C11 monoclonal antibody reacts with mouse CD3ε, a 20 kDa transmembrane cell-surface protein that belongs to the immunoglobulin superfamily. CD3ε is one of five polypeptide chains that combine to form the TCR complex. CD3ε is expressed on T lymphocytes, NK-T cells, and to varying degrees on developing thymocytes. CD3 plays roles in TCR signaling, T lymphocyte activation, and antigen recognition. The 145-2C11 antibody has been shown to induce T lymphocyte activation, proliferation, and apoptosis via binding and stimulating the TCR. Additionally, the 145-2C11 antibody has been reported to block the binding of the 17A2 antibody to CD3ε+ T lymphocytes.

The MR-1 monoclonal antibody reacts with mouse CD154 also known as CD40 ligand. CD154 exists as a 39 kDa accessory molecule and belongs to the TNF superfamily of cytokines. CD154 is primarily expressed on the surface of activated CD4+ T lymphocytes but can also be expressed by platelets, mast cells, macrophages, basophils, NK cells, B lymphocytes, CD8+ T lymphocytes as well as non-hematopoietic cells including smooth muscle cells, endothelial cells, and epithelial cells. CD154 signals through CD40 and is thought to play a key role in T and B lymphocyte costimulation. The MR-1 monoclonal antibody has been reported to inhibit in vitro activation of B lymphocytes by blocking the binding of CD154 with CD40 on T helper cells as well as inhibit the formation of germinal centers and disrupt antigen-specific T cell responses. Additionally, the MR-1 antibody blocks interactions of T cells and antigen-presenting cells in vitro and blocks the development of experimental autoimmune disease in vivo.

The 37.51 monoclonal antibody reacts with mouse CD28, a 45 kDa costimulatory receptor and a member of the Ig superfamily. CD28 is expressed by thymocytes, most peripheral T cells, and NK cells. CD28 is a receptor for CD80 (B7-1) and CD86 (B7-2). Signaling through CD28 augments IL-2 and IL-2 receptor expression as well as cytotoxicity of CD3-activated T cells. The 37.51 antibody has been shown to stimulate the proliferation and cytokine production by activated T and NK cells and provide a costimulatory signal for CTL induction.

The FGK4.5 monoclonal antibody reacts with mouse CD40 also known as Bp50. CD40 is a 48 kDa type I transmembrane glycoprotein that belongs to the tumor necrosis factor receptor (TNFR) superfamily. CD40 is expressed broadly on antigen-presenting cells (APCs) such as dendritic cells, B cells, macrophages, and monocytes as well as non-immune endothelial cells, basal epithelial cells, and a range of tumors. Upon binding to its ligand CD154, CD40 acts as a costimulatory molecule for the activation of B cells, dendritic cells, monocytes, and other APCs. CD40 plays roles in B cell activation, differentiation, proliferation and Ig isotype switching as well as dendritic cell maturation. Agonistic CD40 monoclonal antibodies have been shown to activate APCs and promote anti-tumor T cell responses. The FGK4.5 antibody is an agonistic antibody that has been shown to activate CD40 expressing APCs. FGK4.5 can also be used to inhibit CD40/CD154 interaction in vitro and in vivo.

The 16-10A1 monoclonal antibody reacts with mouse CD80 also known as B7-1. CD80 is a 60 kDa Ig superfamily member and is expressed by activated B cells and constitutively by monocytes and dendritic cells. This ligand binds to CD28 to provide a costimulatory signal necessary for T cell activation and survival, and cytokine production. Additionally, CD80 binds to CTLA-4 which inhibits T cells. This antibody has been shown to block CD80 in vivo.

The R17 217.1.3/TIB-219 monoclonal antibody reacts with mouse CD71 also known as transferrin receptor protein 1 (TfR1). CD71 is a 170-180 kDa type II homodimeric transmembrane glycoprotein which is expressed on the surface of proliferating cells, reticulocytes, and erythroid precursors. CD71 plays a role in the control of cellular proliferation and is required for iron import from transferrin into cells by endocytosis. Due to its important role in proliferation and cellular iron intake as well as the fact that many cancerous cells express high levels of CD71 it is being explored as a potential new target in cases of human leukemia & lymphoma. The R17 217.1.3/TIB-219 antibody has been shown to deplete CD71+ erythroid splenocytes.

The 390 monoclonal antibody reacts with mouse CD31, also known as PECAM-1 (platelet endothelial cell adhesion molecule). CD31 is a 130-140 kDa glycoprotein and member of the immunoglobulin superfamily. CD31 is expressed constitutively on the surface of adult and embryonic endothelial cells and is weakly expressed on platelets, granulocytes, monocytes/macrophages, dendritic cells, and T and B cell subsets. CD31 mediates homophilic and heterophilic cell-cell adhesion and is critical for cell-cell interactions. Ligands for CD31 are reported as CD38 and vitronectin receptor (αvβ3 integrin, CD51/CD61). The 390 antibody has been shown to inhibit in vivo functions mediated by CD31.

The AFS98 monoclonal antibody reacts with mouse colony stimulating factor 1 receptor (CSF1R), also known as macrophage colony-stimulating factor receptor (M-CSFR), and CD115. CSF1R is a single-pass type I membrane protein and member of the platelet-derived growth factor receptor family. In mice CSF1R is expressed by monocytes/macrophages, peritoneal exudate cells, plasmacytoid and conventional dendritic cells, and osteoclasts. CSF1R is a receptor for CSF1 and CSF1 signaling through CSF1R regulates the proliferation and differentiation of cells in the monocytic lineage. The AFS98 antibody has been reported to deplete macrophages and block CSFR1 in vivo.

The UC10-4F10-11 monoclonal antibody reacts with mouse CTLA-4 (cytotoxic T lymphocyte antigen-4) also known as CD152. CTLA-4 is a 33 kDa cell surface receptor encoded by the Ctla4 gene that belongs to the CD28 family of the Ig superfamily. CTLA-4 is expressed on activated T and B lymphocytes. CTLA-4 is structurally similar to the T-cell co-stimulatory protein, CD28, and both molecules bind to the B7 family members B7-1 (CD80) and B7-2 (CD86). Upon ligand binding, CTLA-4 negatively regulates cell-mediated immune responses. CTLA-4 plays roles in induction and/or maintenance of immunological tolerance, thymocyte development, and regulation of protective immunity. The critical role of CTLA-4 in immune down-regulation has been demonstrated in CTLA-4 deficient mice, which succumb at 3-5 weeks of age due to the development of a lymphoproliferative disease. CTLA-4 is among a group of inhibitory receptors being explored as cancer treatment targets through immune checkpoint blockade. The UC10-4F10-11 antibody has been shown to promote T cell co-stimulation by blocking CTLA-4 binding to the B7 co-receptors, allowing for CD28 binding.