LCMV NP396 H-2Db peptide

Product Name: LCMV NP396 H-2Db peptide

Sequence One Letter Code: FQPQNGQFI

Sequence Three Letter Code: H-Phe-Gln-Pro-Gln-Asn-Gly-Gln-Phe-Ile-OH

Chemical Formula:C50H71N13O14

Molecular Weight: 1078.3

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: Inflammation and Immunology Research

Source / Species: LCMV

Conjugation: Unconjugated

Code Nacres: NA.26

Application: LCMV NP396–404 (H-2Db) is a synthetic peptide corresponding to residues 396–404 of the lymphocytic choriomeningitis virus nucleoprotein. This fragment represents an immunodominant epitope presented by the H-2Db MHC class I molecule and is extensively used in murine immunology. The peptide robustly stimulates virus-specific CD8⁺ T cell responses and serves as a standard antigen in studies of cytotoxic T lymphocyte activation, effector function, and immune memory formation. It is frequently employed in viral infection models, transgenic systems such as rat insulin promoter–LCMV mice, and adoptive transfer experiments. This peptide supports investigations into antigen processing and presentation, T cell receptor specificity, and mechanisms of antiviral immunity.

Current Research: LCMV NP396–404 (H-2Dᵇ) is a synthetic peptide corresponding to amino acid residues 396–404 of the lymphocytic choriomeningitis virus (LCMV) nucleoprotein. This nonamer epitope is presented by the murine MHC class I molecule H-2Dᵇ and represents one of the most well-characterized immunodominant CD8⁺ T cell epitopes in experimental viral immunology. Due to its high immunogenicity and reproducible T cell activation profile, NP396–404 has become a benchmark antigen in murine antiviral immunity studies. During LCMV infection, viral proteins are processed by the proteasome, and resulting peptide fragments are transported into the endoplasmic reticulum via TAP (transporter associated with antigen processing). NP396–404 binds with high affinity to H-2Dᵇ molecules and is presented on the surface of infected cells. This peptide–MHC complex is recognized by virus-specific CD8⁺ cytotoxic T lymphocytes (CTLs), triggering clonal expansion, effector differentiation, and targeted killing of infected cells. The strength and kinetics of the NP396–404-specific response make it a reliable model for studying antigen-specific CD8⁺ T cell activation. Functionally, NP396–404 robustly stimulates naïve and memory CD8⁺ T cells in vitro and in vivo. Upon recognition, T cells undergo proliferation and acquire effector functions including perforin- and granzyme-mediated cytotoxicity, interferon-γ (IFN-γ) production, and TNF-α secretion. These responses are readily quantified using intracellular cytokine staining, ELISPOT assays, tetramer staining with H-2Dᵇ/NP396 complexes, and cytotoxicity assays. Because of its defined immunodominance, NP396–404 is frequently used as a standard peptide in functional immune readouts. This epitope is central to acute versus chronic LCMV infection models. In acute infection (e.g., LCMV Armstrong strain), NP396–404–specific CD8⁺ T cells expand rapidly and contribute to viral clearance, followed by contraction and formation of long-lived memory populations. In chronic infection models (e.g., LCMV Clone 13), persistent antigen exposure leads to T cell exhaustion characterized by reduced cytokine production, impaired cytotoxicity, and expression of inhibitory receptors such as PD-1. NP396–404 thus provides a tractable system for dissecting mechanisms of T cell exhaustion, checkpoint regulation, and memory differentiation. The peptide is also widely employed in transgenic and adoptive transfer systems. In rat insulin promoter (RIP)-LCMV mouse models, LCMV antigens are expressed in pancreatic β cells, allowing NP396–404–specific CD8⁺ T cells to mediate tissue-specific autoimmunity. This model has been instrumental in studying mechanisms of immune-mediated diabetes, tolerance breakdown, and peripheral tissue destruction. Additionally, T cell receptor (TCR) transgenic mice specific for NP396–404 provide highly controlled systems for analyzing TCR affinity, clonal selection, and antigen dose–response relationships. In antigen processing research, NP396–404 serves as a defined substrate for evaluating proteasomal cleavage patterns, TAP transport efficiency, and peptide–MHC stability. Mutational variants of the epitope are frequently used to assess anchor residue requirements for H-2Dᵇ binding and TCR recognition specificity. These structure–function studies contribute to broader understanding of immunodominance hierarchies and epitope selection. Overall, LCMV NP396–404 (H-2Dᵇ) is a gold-standard CD8⁺ T cell epitope in murine models of viral infection. Its strong immunogenicity, well-defined MHC restriction, and extensive experimental validation make it indispensable for investigations into cytotoxic T lymphocyte activation, effector function, immune memory, T cell exhaustion, and antiviral immunity.