The PK136 monoclonal antibody reacts with mouse NK1.1 also known as CD161b/CD161c, KLRB1, NKR-P1A and Ly-55. NK1.1 is a type II integral membrane glycoprotein with a C-type lectin domain and is encoded by the Klrb1c/NKR-P1C gene. NK1.1 plays roles in NK cell activation and differentiation, IFN-γ production, cytotoxic granule release, and is thought to be involved in the generation of Th2 cells. NK1.1 is predominantly expressed as a disulfide-linked homodimer on NK cells however, it is also expressed on NK-T cells, a rare population of T lymphocytes. NK 1.1 is only expressed by C57BL/6, FVB/N, and NZB strains of mice and not AKR, BALB/c, CBA/J, C3H, DBA/1, DBA/2, NOD, SJL, and 129 strains.

The 2.43 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 2.43 antibody exhibits depleting activity when used in vivo.

The 9H10 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 9H10 antibody has been shown to promote T cell co-stimulation by blocking CTLA-4 binding to the B7 co-receptors, allowing for CD28 binding.

The MAR1-5A3 monoclonal antibody reacts with mouse IFNAR-1 (IFN alpha/beta receptor subunit 1). IFNAR-1 is coexpressed with IFNAR-2 on nearly all cell types and together these two subunits make up the heterodimeric Type I IFN Receptor complex. Type I IFNs (IFN-α/β) bind to the Type I IFN Receptor complex to induce cellular responses including induction of anti-viral, anti-microbial, anti-tumor, and autoimmune responses as well as to regulate the activation, proliferation, and differentiation of many cell types. The MAR1-5A3 antibody has been shown to inhibit Type I IFN receptor signaling in vitro and in vivo.

The YTS 169.4 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 YTS 169.4 antibody exhibits depleting activity when used in vivo.

The 9D9 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 C18.2 monoclonal antibody reacts with mouse interleukin-12 (IL-12) p35. IL-12 is a heterodimeric 70 kDa cytokine consisting of two covalently linked subunits, 40 kDa (p40) and 35 kDa (p35). IL-12 is secreted by activated monocytes, macrophages, and dendritic cells in response to bacterial pathogens or products such as lipopolysaccharides (LPS). IL-12 is a potent regulator of cell-mediated immune responses and plays a key role in the development of Th1 responses, leading to IFNγ and IL-2 production.

The 10F.9G2™ monoclonal antibody reacts with mouse PD-L1 (programmed death ligand 1) also known as B7-H1 or CD274. PD-L1 is a 40 kDa type I transmembrane protein that belongs to the B7 family of the Ig superfamily. PD-L1 is expressed on T lymphocytes, B lymphocytes, NK cells, dendritic cells, as well as IFNγ stimulated monocytes, epithelial cells and endothelial cells. PD-L1 binds to its receptor, PD-1, found on CD4 and CD8 thymocytes as well as activated T and B lymphocytes and myeloid cells. Engagement of PD-L1 with PD-1 leads to inhibition of TCR-mediated T cell proliferation and cytokine production. PD-L1 is thought to play an important role in tumor immune evasion. Induced PD-L1 expression is common in many tumors and results in increased resistance of tumor cells to CD8 T cell mediated lysis. In mouse models of melanoma, tumor growth can be transiently arrested via treatment with antibodies which block the interaction between PD-L1 and PD-1. The 10F.9G2™ antibody has been shown to block the interaction between PD-L1 and PD-1 and between PD-L1 and B7-1 (CD80).

The J43 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 immunoglobulin superfamily. PD-1 is transiently expressed on CD4 and CD8 thymocytes as well as activated T and B lymphocytes and myeloid cells. PD-1 expression declines after successful elimination of antigen. Additionally, Pdcd1 mRNA is expressed in developing B lymphocytes during the pro-B-cell stage. PD-1’s structure includes a ITIM (immunoreceptor tyrosine-based inhibitory motif) suggesting that PD-1 negatively regulates TCR signals. PD-1 signals via binding its two ligands, PD-L1 and PD-L2 both members of the B7 family. Upon ligand binding, PD-1 signaling inhibits T-cell activation, leading to reduced proliferation, cytokine production, and T-cell death. Additionally, PD-1 is known to play key roles in peripheral tolerance and prevention of autoimmune disease in mice as PD-1 knockout animals show dilated cardiomyopathy, splenomegaly, and loss of peripheral tolerance. Induced PD-L1 expression is common in many tumors including squamous cell carcinoma, colon adenocarcinoma, and breast adenocarcinoma. PD-L1 overexpression results in increased resistance of tumor cells to CD8 T cell mediated lysis. In mouse models of melanoma, tumor growth can be transiently arrested via treatment with antibodies which block the interaction between PD-L1 and its receptor PD-1. For these reasons anti-PD-1 mediated immunotherapies are currently being explored as cancer treatments. The J43 antibody has been shown to block the binding of both mouse PD-L1-Ig and mouse PD-L2-Ig to PD-1.

The 1D11.16.8 monoclonal antibody reacts with mouse, human, rat, monkey, hamster, canine and bovine TGF-β (transforming growth factor beta) isoforms 1, 2 and 3. TGF-β is a multifunctional cytokine that regulates the proliferation of epithelial cells, endothelial cells, fibroblasts, neurons, lymphoid cells including T lymphocytes and NK cells, and other hematopoietic cell types. TGF-β also regulates the activities of activated macrophages and the development of regulatory T cells. Additionally, TGF-β plays roles in immune function, tissue remodeling and wound repair. TGF-β exists as five highly similar isoforms (TGF-β 1-5) with homologies of 70-80%. TGF-β1 is synthesized by the enzymatic cleavage of a long precursor TGF-β1 polypeptide encoded by the TGFB1 gene which yields the mature protein and the Latency Associated Peptide (LAP). The LAP and mature TGF-β1 non-covalently associate during secretion. TGF-β is ubiquitously expressed by many cell types including macrophages and platelets which express high levels of TGF-β. TGF-β signaling has been shown to plays roles in cancer, autoimmune diseases, asthma, heart disease, and diabetes. Its importance is illustrated by TGF-β knockout mice which show defects in hematopoiesis and endothelial differentiation, and die of overwhelming inflammation. The 1D11.16.8 monoclonal antibody is a neutralizing antibody.

The C398.4A monoclonal antibody reacts with mouse, human, rat and monkey ICOS (inducible T cell co-stimulator), also known as CD278. ICOS is a 47-57 kDa homodimeric glycoprotein belonging to the CD28 family of costimulatory molecules. ICOS is expressed on activated T cells and upon ICOSL binding, co-stimulates T and B cell responses. The ligand Is expressed on antigen presenting cells including splenic B cells, dendritic cells, and macrophages. ICOS signaling is also thought to be important for maintaining regulatory T cell homeostasis. The C398.4A antibody is commonly used to costimulate T cell activation and proliferation in vitro. C398.4A does not block the binding of ICOS to ICOSL.

The OX-86 monoclonal antibody reacts with mouse OX-40 also known as CD134. OX-40 is a 50 kDa type I membrane glycoprotein and a member of the TNF receptor superfamily. OX-40 is expressed on activated CD4 and CD8 T cells, but is not found on resting naïve T cells or most resting memory T cells. Although it was originally thought that OX-40 expression was restricted to activated conventional T cells, it has now been visualized on activated regulatory T cells, NKT cells, NK cells, and neutrophils. OX-40 plays a major role in regulating both CD4 and CD8 T cell clonal expansion. It provides a costimulatory signal to an antigen-reacting naive T cells to prolong proliferation, as well as augment the production of several cytokines. This is demonstrated by OX-40 knockout mice which generate fewer primary effector CD4 T cells after immunization. Furthermore, in vivo treatment with an agonist antibody to OX-40 has been shown to strongly enhance the generation of antigen-specific effector T cells and prevent the induction of T cell tolerance. The OX-86 antibody is an agonistic antibody that has been shown to delay tumor growth in vivo.

The 100D3 monoclonal antibody reacts with mouse osteopontin (OPN), also known as SPP1. Osteopontin is a secreted arginine-glycine-aspartic acid (RGD)-containing glycoprotein that was originally isolated from bone. Osteopontin has been found in kidney, vascular tissues, biological fluids, and various tumor tissues. Osteopontin interacts with integrins and CD44 and regulates diverse biological processes including bone development, immune responses, and oncogenesis. Osteopontin is elevated in human colorectal cancer and is thought to function as an immune checkpoint. The 100D3 antibody is a blocking antibody that has been shown to increase the efficacy of tumor-specific CTLs in killing colon tumor cells in vitro and suppress colon tumor growth in tumor-bearing mice in vivo.

The C1.18.4 monoclonal antibody is ideal for use as a non-reactive isotype-matched control for mouse IgG2a antibodies in most in vivo and in vitro applications.

The MOPC-21 monoclonal antibody is ideal for use as a non-reactive isotype-matched control for mouse IgG1 antibodies in most in vivo and in vitro applications.