Lab Meeting #2

Introduction to Salivary Gland Research

• Background on Salivary Glands

  • Three main glands: parotid, submandibular, and sublingual.

  • These glands produce saliva, composed of water, salts, and digestive enzymes.

  • Numerous smaller salivary glands exist throughout the facial region.

Cell Types in Salivary Glands

• Key Types of Cells

  • Acinar Cells: Produce saliva; structured into clusters with lumens for secretion.

  • Myoepithelial Cells: Provide contractility, move saliva through ducts.

    • Function: Contract in response to stimuli (e.g., food smells) via activation of the parasympathetic nervous system.

Importance of Salivary Glands

• Effects of Dysfunction

  • Essential for oral health and digestion, preventing infections, and maintaining moisture in the mouth.

  • Loss of saliva production can severely affect quality of life, especially post-radiation therapy for cancers.

• Research Relevance

  • Rising need for therapies due to radiation-induced damage to salivary glands.

  • Treatments like amifostine have limited success; 70% of patients still suffer.

Research Objectives

• Tissue Engineering Approach

  • Aim to isolate cells from patients undergoing tumor removal and radiation.

  • Develop a hydrogel scaffold for regenerative therapy

  • Reintroduce engineered salivary gland tissue post-radiation to restore function.

Stem Cell Research

• HSPC Characterization

  • Human Salivary Precursor Cells (HSPCs) have capacity to differentiate into acinar and myoepithelial cells.

  • Isolated from tissue donations during surgeries for tumors.

Hydrogel Development

• Biomaterials Use

  • Primary component: Hyaluronic Acid (HA).

  • Thiol modification allows for integration of ECM proteins, enhancing cell attachment and movement.

  • Adjusting degradation rates influences cell behavior and differentiation.

Experimental Findings

• Cell Behavior

  • HSPCs showed successful branching and lumen formation influenced by hydrogel's properties.

  • Correct orientation of Golgi bodies crucial for acinar function; achieved in 50% degradable gels.

Challenges Encountered

• Cell Polarization Issues

  • Incorrect orientation of organelles hindered lumen development.

  • Investigated ROCK inhibition effects to promote correct cell polarization.

Mediation Strategies

• Media Optimization

  • Tested various culture media combinations to sustain cell growth while preventing differentiation.

• RNA Sequencing

  • Evaluated gene expression to confirm healthy phenotype and cellular characteristics; successful manipulations resulted in desired differentiation markers.

Future Directions

• Additional Co-culture Experiments

  • Goals: Enhance intercellular interactions and growth factor gradients between stem and vascular endothelial cells to replicate salivary gland physiology.

• Validation and Functionality

  • Aim to establish a functioning salivary gland model to address and combat dysfunction post-therapy.