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Human Positive Regulation of Regulatory t Cell Differentiation

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: Complement Regulatory Protein; Membrane Cofactor Protein (CD46) is a type 1 membrane protein that plays an important inhibitory role in the complement system (1). CD46 exhibits a cofactor activity that promotes inactivation of C3b and C4b by serum factor 1, thereby protecting host (self) cells from complement-dependent cytotoxicity (1,2). The importance of CD46 to complement regulation is underscored by the observation that genetic loss of CD46 leads to development of atypical hemolytic-uremic syndrome (aHUS), a disease characterized by uncontrolled complement activation (2,3). In addition to its role in complement inactivation, CD46 can function as a receptor for selected bacteria and viruses (4), and is reportedly required for proper fusion of spermatozoa to the oocyte membrane during fertilization (5). CD46 is implicated in the development and/or progression of selected cancer types. For example, research studies show elevated CD46 expression in medulloblastoma tumor samples (6), while CD46 expression has been linked with poor prognosis in breast cancer (7). It has been suggested that upregulation of CD46 may serve to protect cancer cells from complement-dependent cytotoxicity, thereby evading destruction by the immune system (8,9).

$129
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: HLA-G (HLA-G histocompatibility antigen, class I, G) is a non-classical MHC molecule expressed by trophoblasts in placenta, thymic epithelial cells, and some tumors. Alternative splicing leads to generation of at least six isoforms, four that are transmembrane proteins and two that are soluble (1-4). It is an inhibitory molecule involved in immune tolerance and escape, originally studied for its role in maternal tolerance of the fetus during pregnancy (1-5). HLA-G binds ILT2, ILT4, and KIR2DL4, playing a role in the regulation of natural killer, T, and monocyte/macrophage cells (4-5). Its involvement in evasion of immune response makes it a potential target for immunotherapy (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Interleukin-2 (IL-2) is a T cell stimulatory cytokine best known for inducing T cell proliferation and NK cell proliferation and activation (1,2). IL-2 also promotes peripheral development of regulatory T cells (Tregs) (3,4). Conversely, IL-2 is involved in the activation-induced cell death (AICD) that is observed post T cell expansion by increasing levels of Fas on CD4+ T cells (5). The effects of IL-2 are mediated through a trimeric receptor complex consisting of IL-2Rα, IL-2Rβ, and the common gamma chain, γc (1,2). IL-2Rα binds exclusively to IL-2 with low affinity and increases the binding affinity of the whole receptor complex including IL-2Rβ and γc subunits. IL-15 also binds to IL-2Rβ (1,2). γc is used by other cytokines including IL-4, IL-7, IL-9, IL-15, and IL-21 (1,2). Binding of IL-2 initiates signaling cascades involving Jak1, Jak3, Stat5, and the PI3K/Akt pathways (1,2).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Interferon regulatory factors (IRFs) comprise a family of transcription factors that function within the Jak/Stat pathway to regulate interferon (IFN) and IFN-inducible gene expression in response to viral infection (1). IRFs play an important role in pathogen defense, autoimmunity, lymphocyte development, cell growth, and susceptibility to transformation. The IRF family includes nine members: IRF-1, IRF-2, IRF-9/ISGF3γ, IRF-3, IRF-4 (Pip/LSIRF/ICSAT), IRF-5, IRF-6, IRF-7, and IRF-8/ICSBP. All IRF proteins share homology in their amino-terminal DNA-binding domains. IRF family members regulate transcription through interactions with proteins that share similar DNA-binding motifs, such as IFN-stimulated response elements (ISRE), IFN consensus sequences (ICS), and IFN regulatory elements (IRF-E) (2).

$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated IRF-1 (D5E4) XP® Rabbit mAb #8478.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry

Background: Interferon regulatory factors (IRFs) comprise a family of transcription factors that function within the Jak/Stat pathway to regulate interferon (IFN) and IFN-inducible gene expression in response to viral infection (1). IRFs play an important role in pathogen defense, autoimmunity, lymphocyte development, cell growth, and susceptibility to transformation. The IRF family includes nine members: IRF-1, IRF-2, IRF-9/ISGF3γ, IRF-3, IRF-4 (Pip/LSIRF/ICSAT), IRF-5, IRF-6, IRF-7, and IRF-8/ICSBP. All IRF proteins share homology in their amino-terminal DNA-binding domains. IRF family members regulate transcription through interactions with proteins that share similar DNA-binding motifs, such as IFN-stimulated response elements (ISRE), IFN consensus sequences (ICS), and IFN regulatory elements (IRF-E) (2).

$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometric analysis in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated IRF-1 (D5E4) XP® Rabbit mAb #8478.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry

Background: Interferon regulatory factors (IRFs) comprise a family of transcription factors that function within the Jak/Stat pathway to regulate interferon (IFN) and IFN-inducible gene expression in response to viral infection (1). IRFs play an important role in pathogen defense, autoimmunity, lymphocyte development, cell growth, and susceptibility to transformation. The IRF family includes nine members: IRF-1, IRF-2, IRF-9/ISGF3γ, IRF-3, IRF-4 (Pip/LSIRF/ICSAT), IRF-5, IRF-6, IRF-7, and IRF-8/ICSBP. All IRF proteins share homology in their amino-terminal DNA-binding domains. IRF family members regulate transcription through interactions with proteins that share similar DNA-binding motifs, such as IFN-stimulated response elements (ISRE), IFN consensus sequences (ICS), and IFN regulatory elements (IRF-E) (2).

$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 647 fluorescent dye and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated IRF-1 (D5E4) XP® Rabbit mAb #8478.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry

Background: Interferon regulatory factors (IRFs) comprise a family of transcription factors that function within the Jak/Stat pathway to regulate interferon (IFN) and IFN-inducible gene expression in response to viral infection (1). IRFs play an important role in pathogen defense, autoimmunity, lymphocyte development, cell growth, and susceptibility to transformation. The IRF family includes nine members: IRF-1, IRF-2, IRF-9/ISGF3γ, IRF-3, IRF-4 (Pip/LSIRF/ICSAT), IRF-5, IRF-6, IRF-7, and IRF-8/ICSBP. All IRF proteins share homology in their amino-terminal DNA-binding domains. IRF family members regulate transcription through interactions with proteins that share similar DNA-binding motifs, such as IFN-stimulated response elements (ISRE), IFN consensus sequences (ICS), and IFN regulatory elements (IRF-E) (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Cytotoxic T-lymphocyte protein 4 (CTLA-4, CD152) is an Ig superfamily member that negatively regulates early T cell activation (1-4). The CTLA-4 protein is primarily expressed on T cells, including CD8+ cytotoxic T cells, CD4+ helper T cells, and CD4+/FoxP3+ regulatory T cells (1,2). CTLA-4 protein competes with CD28 for B7.1 (CD80) and B7.2 (CD86) binding at the cell surface, which results in the down regulation of T cell activity (5). The activation of SHP-2 and PP2A downstream of CTLA-4 attenuates TCR signaling (6). Research studies indicate that CTLA4 knockout mice display lymphoproliferative disorders leading to early death, confirming the role of CTLA-4 as a negative regulator of T cells (7). Mutations in the corresponding CTLA4 gene are associated with multiple disorders, including insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, and type V autoimmune lymphoproliferative syndrome (8,9). Additional studies demonstrate that CTLA-4 blockade is an effective strategy for tumor immunotherapy (10-12).

$210
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometric analysis in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated CTLA-4 (D4E9I) Rabbit mAb #15119.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Cytotoxic T-lymphocyte protein 4 (CTLA-4, CD152) is an Ig superfamily member that negatively regulates early T cell activation (1-4). The CTLA-4 protein is primarily expressed on T cells, including CD8+ cytotoxic T cells, CD4+ helper T cells, and CD4+/FoxP3+ regulatory T cells (1,2). CTLA-4 protein competes with CD28 for B7.1 (CD80) and B7.2 (CD86) binding at the cell surface, which results in the down regulation of T cell activity (5). The activation of SHP-2 and PP2A downstream of CTLA-4 attenuates TCR signaling (6). Research studies indicate that CTLA4 knockout mice display lymphoproliferative disorders leading to early death, confirming the role of CTLA-4 as a negative regulator of T cells (7). Mutations in the corresponding CTLA4 gene are associated with multiple disorders, including insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, and type V autoimmune lymphoproliferative syndrome (8,9). Additional studies demonstrate that CTLA-4 blockade is an effective strategy for tumor immunotherapy (10-12).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Cytotoxic T-lymphocyte protein 4 (CTLA-4, CD152) is an Ig superfamily member that negatively regulates early T cell activation (1-4). The CTLA-4 protein is primarily expressed on T cells, including CD8+ cytotoxic T cells, CD4+ helper T cells, and CD4+/FoxP3+ regulatory T cells (1,2). CTLA-4 protein competes with CD28 for B7.1 (CD80) and B7.2 (CD86) binding at the cell surface, which results in the down regulation of T cell activity (5). The activation of SHP-2 and PP2A downstream of CTLA-4 attenuates TCR signaling (6). Research studies indicate that CTLA4 knockout mice display lymphoproliferative disorders leading to early death, confirming the role of CTLA-4 as a negative regulator of T cells (7). Mutations in the corresponding CTLA4 gene are associated with multiple disorders, including insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, and type V autoimmune lymphoproliferative syndrome (8,9). Additional studies demonstrate that CTLA-4 blockade is an effective strategy for tumor immunotherapy (10-12).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Forkhead box (Fox) proteins are a family of evolutionarily conserved transcription factors containing a sequence known as Forkhead box or winged helix DNA binding domain (1). The human genome contains 43 Fox proteins that are divided into subfamilies. The FoxP subfamily has four members, FoxP1 - FoxP4, which are broadly expressed and play important roles in organ development, immune response and cancer pathogenesis (2-4). The FoxP subfamily has several characteristics that are atypical among Fox proteins: their Forkhead domain is located at the carboxy-terminal region and they contain motifs that promote homo- and heterodimerization. FoxP proteins usually function as transcriptional repressors (4,5).FoxP3 is crucial for the development of T cells with regulatory properties (Treg) (6). Mutations in FoxP3 are associated with immune dysregulation, polyendocrinopathy, enteropathy, and X-linked syndrome (IPEX) (7), while overexpression in mice causes severe immunodeficiency (8). Research studies have shown that FoxP3 functions as a tumor suppressor in several types of cancer (9-11).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Western Blotting

Background: Forkhead box (Fox) proteins are a family of evolutionarily conserved transcription factors containing a sequence known as Forkhead box or winged helix DNA binding domain (1). The human genome contains 43 Fox proteins that are divided into subfamilies. The FoxP subfamily has four members, FoxP1 - FoxP4, which are broadly expressed and play important roles in organ development, immune response and cancer pathogenesis (2-4). The FoxP subfamily has several characteristics that are atypical among Fox proteins: their Forkhead domain is located at the carboxy-terminal region and they contain motifs that promote homo- and heterodimerization. FoxP proteins usually function as transcriptional repressors (4,5).FoxP3 is crucial for the development of T cells with regulatory properties (Treg) (6). Mutations in FoxP3 are associated with immune dysregulation, polyendocrinopathy, enteropathy, and X-linked syndrome (IPEX) (7), while overexpression in mice causes severe immunodeficiency (8). Research studies have shown that FoxP3 functions as a tumor suppressor in several types of cancer (9-11).

$210
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated CTLA-4 (D4E9I) Rabbit mAb #15119.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Cytotoxic T-lymphocyte protein 4 (CTLA-4, CD152) is an Ig superfamily member that negatively regulates early T cell activation (1-4). The CTLA-4 protein is primarily expressed on T cells, including CD8+ cytotoxic T cells, CD4+ helper T cells, and CD4+/FoxP3+ regulatory T cells (1,2). CTLA-4 protein competes with CD28 for B7.1 (CD80) and B7.2 (CD86) binding at the cell surface, which results in the down regulation of T cell activity (5). The activation of SHP-2 and PP2A downstream of CTLA-4 attenuates TCR signaling (6). Research studies indicate that CTLA4 knockout mice display lymphoproliferative disorders leading to early death, confirming the role of CTLA-4 as a negative regulator of T cells (7). Mutations in the corresponding CTLA4 gene are associated with multiple disorders, including insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, and type V autoimmune lymphoproliferative syndrome (8,9). Additional studies demonstrate that CTLA-4 blockade is an effective strategy for tumor immunotherapy (10-12).

$448
50 sections
1 Kit
The PD-L1, FoxP3, CD8α Multiplex IHC Antibody Panel enables researchers to simultaneously detect these targets in paraffin-embedded tissues using tyramide signal amplification. Each antibody in the panel has been validated for this approach. For recommended staining conditions optimized specifically for this antibody panel please refer to Table 1 on the Data Sheet.
REACTIVITY
Human

Background: The field of cancer immunotherapy is focused on empowering the immune system to fight cancer. This approach has seen recent success in the clinic with targeting immune checkpoint control proteins, such as PD-1 (1,2). Despite this success, clinical biomarkers that predict response to therapeutic strategies involving PD-1 receptor blockade are still under investigation (3-5). While PD-L1 expression has been linked with an increased likelihood of response to anti-PD-1 therapy, research studies have shown that additional factors, such as tumor-immune infiltration and the ratio of effector to regulatory T cells within the tumor, could play a significant role in predicting treatment outcome (6-9).

$269
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: IHC-Leica® Bond™, Immunohistochemistry (Paraffin)

Background: Forkhead box (Fox) proteins are a family of evolutionarily conserved transcription factors containing a sequence known as Forkhead box or winged helix DNA binding domain (1). The human genome contains 43 Fox proteins that are divided into subfamilies. The FoxP subfamily has four members, FoxP1 - FoxP4, which are broadly expressed and play important roles in organ development, immune response and cancer pathogenesis (2-4). The FoxP subfamily has several characteristics that are atypical among Fox proteins: their Forkhead domain is located at the carboxy-terminal region and they contain motifs that promote homo- and heterodimerization. FoxP proteins usually function as transcriptional repressors (4,5).FoxP3 is crucial for the development of T cells with regulatory properties (Treg) (6). Mutations in FoxP3 are associated with immune dysregulation, polyendocrinopathy, enteropathy, and X-linked syndrome (IPEX) (7), while overexpression in mice causes severe immunodeficiency (8). Research studies have shown that FoxP3 functions as a tumor suppressor in several types of cancer (9-11).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The most well characterized nuclear receptor corepressors are SMRT (silencing mediator for retinoic acid and thyroid hormone receptors) and its close paralog NCoR1 (nuclear receptor corepressor) (1,2). NCoR1 functions to transcriptionally silence various unliganded, DNA bound non-steroidal nuclear receptors by serving as a large molecular scaffold that bridges the receptors with multiple chromatin remodeling factors that repress nuclear receptor-mediated gene transcription, in part, through deacetylation of core histones surrounding target promoters. Indeed, the N-terminal portion of NCoR1 possesses multiple distinct transcriptional repression domains (RDs) reponsible for the recruitment of additional components of the corepressor complex such as HDACs, mSin3, GPS2, and TBL1/TBLR1. In between the RDs lies a pair of potent repressor motifs known as SANT motifs (SWI3, ADA2, N-CoR, and TFIIIB), which recruit HDAC3 and histones to the repressor complex in order to enhance HDAC3 activity (3). The C-terminal portion of NCoR1 contains multiple nuclear receptor interaction domains (NDs), each of which contains a conserved CoRNR box (or L/I-X-X-I/V-I) motif that allow for binding to various unliganded nuclear hormone receptors such as thyroid hormone (THR) and retinoic acid (RAR) receptors (4,5).Recent genetic studies in mice have not only corroborated the wealth of biochemical studies involving NCoR1 but have also provided significant insight regarding the function of NCoR1 in mammalian development and physiology. Although it has been observed that loss of Ncor1 does not affect early embyonic development, likely due to compensation by Smrt, embryonic lethality ultimately results during mid-gestation, largely due to defects in erythropoesis and thymopoesis (6). Another study demonstrated that the NDs of NCoR1 are critical for its ability to function in a physiological setting as a transcriptional repressor of hepatic THR and Liver X Receptor (LXR) (7).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, IHC-Leica® Bond™, Immunohistochemistry (Paraffin), Western Blotting

Background: Galectins are a family of β-galactose binding proteins that are characterized by an affinity for poly-N-acetyllactosamine-enriched glycoconjugates and a carbohydrate-binding site (1,2). Members of the galectin family have been implicated in a variety of biological functions, including cell adhesion (3), growth regulation (4), cytokine production (5), T-cell apoptosis (6), and immune responses (7).Galectin-9 is induced by proinflammatory stimuli, including IFN-γ, TNF-α, and TLR ligands, and regulates various immune responses through interaction with its ligand TIM-3 (8, 9). Binding of galectin-9 to TIM-3 expressed by Th1 CD4 T cells resulted in T cell death (9). On the other hand, galectin-9 treatment of tumor-bearing mice increased the number of IFN-γ-producing TIM-3+ CD8 T cells and TIM-3+ dendritic cells (10). Transgenic overexpression of either TIM-3 or galectin-9 in mice led to an increase in cells with a myeloid-derived suppressor cell phenotype and inhibition of immune responses (11). CD44 is also proposed to be a receptor for galectin-9, and interaction of galectin-9 with CD44 expressed by induced regulatory T (iTreg) cells enhanced the stability of function of iTreg cells. In addition, galectin-9 was recently demonstrated to bind Dectin-1 expressed by pancreatic ductal adenocarcinoma-infiltrating macrophages, resulting in tolerogenic macrophage reprogramming and suppression of anti-tumor immunity. Increased galectin-9 expression has been observed in several cancer types, including lung, liver, breast, and kidney (12). Alternative splicing of the galectin-9 transcript leads to several isoforms (13).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Chromatin IP, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: The most well characterized nuclear receptor corepressors are SMRT (silencing mediator for retinoic acid and thyroid hormone receptors) and its close paralog NCoR1 (nuclear receptor corepressor) (1,2). NCoR1 functions to transcriptionally silence various unliganded, DNA bound non-steroidal nuclear receptors by serving as a large molecular scaffold that bridges the receptors with multiple chromatin remodeling factors that repress nuclear receptor-mediated gene transcription, in part, through deacetylation of core histones surrounding target promoters. Indeed, the N-terminal portion of NCoR1 possesses multiple distinct transcriptional repression domains (RDs) reponsible for the recruitment of additional components of the corepressor complex such as HDACs, mSin3, GPS2, and TBL1/TBLR1. In between the RDs lies a pair of potent repressor motifs known as SANT motifs (SWI3, ADA2, N-CoR, and TFIIIB), which recruit HDAC3 and histones to the repressor complex in order to enhance HDAC3 activity (3). The C-terminal portion of NCoR1 contains multiple nuclear receptor interaction domains (NDs), each of which contains a conserved CoRNR box (or L/I-X-X-I/V-I) motif that allow for binding to various unliganded nuclear hormone receptors such as thyroid hormone (THR) and retinoic acid (RAR) receptors (4,5).Recent genetic studies in mice have not only corroborated the wealth of biochemical studies involving NCoR1 but have also provided significant insight regarding the function of NCoR1 in mammalian development and physiology. Although it has been observed that loss of Ncor1 does not affect early embyonic development, likely due to compensation by Smrt, embryonic lethality ultimately results during mid-gestation, largely due to defects in erythropoesis and thymopoesis (6). Another study demonstrated that the NDs of NCoR1 are critical for its ability to function in a physiological setting as a transcriptional repressor of hepatic THR and Liver X Receptor (LXR) (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Peptide ELISA (DELFIA), Western Blotting

Background: IFN-γ plays key roles in both the innate and adaptive immune response. IFN-γ activates the cytotoxic activity of innate immune cells, such as macrophages and NK cells (1,2). IFN-γ production by NK cells and antigen presenting cells (APCs) promotes cell-mediated adaptive immunity by inducing IFN-γ production by T lymphocytes, increasing class I and class II MHC expression, and enhancing peptide antigen presentation (1). The anti-viral activity of IFN-γ is due to its induction of PKR and other regulatory proteins. Binding of IFN-γ to the IFNGR1/IFNGR2 complex promotes dimerization of the receptor complexes to form the (IFNGR1/IFNGR2)2 -IFN-γ dimer. Binding induces a conformational change in receptor intracellular domains and signaling involves Jak1, Jak2, and Stat1 (3). The critical role of IFN-γ in amplification of immune surveillance and function is supported by increased susceptibility to pathogen infection by IFN-γ or IFNGR knockout mice and in humans with inactivating mutations in IFNGR1 or IFNGR2. IFN-γ also appears to have a role in atherosclerosis (4).

$293
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: IFN-γ plays key roles in both the innate and adaptive immune response. IFN-γ activates the cytotoxic activity of innate immune cells, such as macrophages and NK cells (1,2). IFN-γ production by NK cells and antigen presenting cells (APCs) promotes cell-mediated adaptive immunity by inducing IFN-γ production by T lymphocytes, increasing class I and class II MHC expression, and enhancing peptide antigen presentation (1). The anti-viral activity of IFN-γ is due to its induction of PKR and other regulatory proteins. Binding of IFN-γ to the IFNGR1/IFNGR2 complex promotes dimerization of the receptor complexes to form the (IFNGR1/IFNGR2)2 -IFN-γ dimer. Binding induces a conformational change in receptor intracellular domains and signaling involves Jak1, Jak2, and Stat1 (3). The critical role of IFN-γ in amplification of immune surveillance and function is supported by increased susceptibility to pathogen infection by IFN-γ or IFNGR knockout mice and in humans with inactivating mutations in IFNGR1 or IFNGR2. IFN-γ also appears to have a role in atherosclerosis (4).