What is LCK Protein

      What is LCK Protein?

      The LCK protein, a member of the Src family of non-receptor tyrosine kinases, is a linchpin in cellular signaling, particularly within T cells. Predominantly expressed in these white blood cells, LCK plays a pivotal role in orchestrating immune responses. Structurally, LCK exhibits distinct functional domains, including Src homology 2 (SH2) and Src homology 3 (SH3) domains, alongside a kinase domain. This molecular architecture allows LCK to engage in intricate protein-protein interactions, forming the foundation for its diverse functionalities.

      The Function of LCK Protein

      LCK's primary function revolves around T cell activation, a fundamental step in immune responses. Upon encountering antigens, LCK is activated, initiating a cascade of events critical for the immune system's efficacy. Through phosphorylation of key signaling molecules such as the T-cell receptor (TCR) and co-receptors CD4 or CD8, LCK finely tunes the immune response. Additionally, LCK modulates immune checkpoints, ensuring a delicate balance between activation and suppression. Dysregulation of LCK can lead to autoimmune diseases, immunodeficiency disorders, or contribute to cancer evasion of immune surveillance.

      LCK-Related Diseases

      Autoimmune Diseases: Diseases like rheumatoid arthritis and lupus showcase the consequences of LCK dysregulation. An imbalance in immune responses triggered by aberrant LCK activity leads to the immune system attacking the body's own tissues.

      Immunodeficiency Disorders: Deficiencies in LCK activity result in weakened immune responses, rendering individuals susceptible to infections. Unraveling LCK's role in immunodeficiency disorders offers insights for targeted therapeutic interventions.

      Cancer: LCK emerges as a potential target in cancer therapy due to its involvement in immune surveillance. Modulating LCK activity presents an opportunity to enhance the immune response against tumor cells, disrupting immune evasion mechanisms employed by cancer cells.

      LCK Related Signaling Pathways

      TCR Signaling Pathway: At the forefront of T cell activation is the TCR signaling pathway, where LCK phosphorylates the TCR, initiating a cascade that culminates in T cell activation. Understanding the nuances of LCK's participation in this pathway is crucial for unraveling immune responses.

      Co-receptor Signaling: LCK's interaction with CD4 and CD8 co-receptors amplifies the immune response. Phosphorylation of these co-receptors enhances the affinity of TCR to antigens, ensuring a robust and effective T cell activation process.

      Immune Checkpoint Regulation: LCK's influence on immune checkpoints, such as PD-1 and CTLA-4, highlights its role in fine-tuning immune responses. This regulatory function positions LCK as a potential target for therapeutic interventions aimed at enhancing anti-cancer immune responses.

      The proposed model of TCR triggering mechanism. (Filipp, D., et al. 2012)

      Figure 1. The proposed model of TCR triggering mechanism. (Filipp, D., et al. 2012)

      Applications of LCK in Biomedical Research

      Diagnostic Biomarker: Monitoring LCK levels and activity serves as a diagnostic biomarker, offering insights into diseases characterized by immune dysfunction. Early detection of LCK dysregulation can facilitate timely interventions.

      Prognostic Indicator: In the context of cancer, evaluating LCK expression and activity provides a prognostic indicator. High LCK activity in tumor-infiltrating T cells may signify a robust anti-tumor immune response, guiding treatment strategies.

      Therapeutic Target: Modulating LCK activity emerges as a promising therapeutic strategy. Small molecules or biologics targeting LCK could enhance T cell activation, overcoming immune suppression, and improving the efficacy of existing immunotherapies.

      Drug Development: Understanding LCK's role in signal pathways offers a foundation for drug development. Researchers are actively exploring compounds that selectively target LCK, with the aim of developing novel therapies for immune-related disorders and cancers.

      The LCK protein's intricate involvement in immune regulation, signal pathways, and its potential applications in biomedical contexts underscore its significance in the realm of molecular biology. As research continues to unveil the complexities of LCK, the prospect of leveraging its functions for diagnostic, prognostic, and therapeutic advancements in various diseases becomes increasingly tangible.

      Recommended Products for LCK Protein

      Cat.# Species Product name Source (Host) Tag
      LCK-692H Human Active Recombinant Human LCK, His-tagged S.frugiperda His
      LCK-273H Human Recombinant Human LCK, MYC/DDK-tagged HEK293 Myc/DDK
      LCK-174H Human Recombinant Human LCK Protein (SH3 Domain), GST tagged E.coli GST
      LCK-776H Human Recombinant Human LCK, GST tagged Insect Cell GST
      LCK-2360HFL Human Recombinant Full Length Human LCK, Flag-tagged Mamanlian cells Flag
      LCK-3524H Human Recombinant Human LCK protein, His-tagged E.coli His
      LCK-8482HF Human Active Recombinant Full Length Human LCK Protein, BTN-tagged Insect (sf21) BTN
      Lck-1300M Mouse Recombinant Mouse Lck Protein, MYC/DDK-tagged HEK293T MYC/DDK
      LCK-3365R Rat Recombinant Rat LCK Protein Mammalian Cell His
      LCK-220Z Zebrafish Recombinant Zebrafish LCK Mammalian Cell His

      Reference

      • Filipp, D., et al. Lck, Membrane Microdomains, and TCR Triggering Machinery: Defining the New Rules of Engagement. Front Immunol. 2012, 3: 155.