Electrostatic Analysis Approach for Measuring Zeta Potential of M-cells In Mucosal Epithelia - PowerPoint PPT Presentation

Loading...

PPT – Electrostatic Analysis Approach for Measuring Zeta Potential of M-cells In Mucosal Epithelia PowerPoint presentation | free to download - id: 60da02-MWIwM



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Electrostatic Analysis Approach for Measuring Zeta Potential of M-cells In Mucosal Epithelia

Description:

Title: Slide 1 Author: vrodgers Last modified by: Nilufer Created Date: 11/4/2007 2:04:43 AM Document presentation format: On-screen Show (4:3) Company – PowerPoint PPT presentation

Number of Views:82
Avg rating:3.0/5.0
Slides: 21
Provided by: vrod
Learn more at: http://www.engr.ucr.edu
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Electrostatic Analysis Approach for Measuring Zeta Potential of M-cells In Mucosal Epithelia


1
Electrostatic Analysis Approach for Measuring
Zeta Potential of M-cells In Mucosal Epithelia
  • Nilufer I. Nurinova
  • Dr. David Lo
  • Dr. Victor G. J. Rodgers
  • 08/20/2009

2
Outline
  • Motivations
  • Overview
  • Rationale
  • Objectives
  • Experimental methods
  • Data collection and analysis
  • Conclusion
  • Future work
  • Acknowledgements

3
Motivations
  • Characterize electrostatic behavior of intestinal
    epithelia
  • Better procedure may be achieved in vaccine
    delivery protocol

4
Overview
  • M-cells are major component of follicle-associated
    epithelium and found in 1
  • Peyer's Patches of gut-associated lymphoid tissue
    (GALT)
  • Mucosal-associated lymphoid tissue (MALT) sites
    outside the gastrointestinal tract
  • In the gastrointestinal tract, M-cells play an
    important role in transport of antigen from the
    lumen of the small intestine to mucosal lymphoid
    tissues where initiation and processing of immune
    responses occur

1 Mary Petzke, MD-PhD Harvard Medical School
and Childrens Hospital, 2000 Images provided
by David Lo, UCR, 2009
5
Mucosal M-cell Targeting
  • M-cells surface lack of brush border and
    glycocalyx which usually serve as a barrier in
    intestinal epithelia 1
  • Understanding the mechanism by which M-cells
    sample antigens can provide insight to mucosal
    vaccination methods

5 µm
1 Mary Petzke, MD-PhD Harvard Medical School
and Childrens Hospital , 2000 Images are
courtesy of Dr, David Lo, Biomedical Sciences
Dept. UC Riverside, CA
6
Selective Uptake by Mucosal Epithelium
  • Specific bacteria (fixed and fluorescently
    labeled) taken up by Caco-2BBe epithelial cells,
    with uptake quantified by flow cytometry
  • Enhanced by cytokine treatment, highly
    significant effect for S. Aureus and Yersinia

Images are courtesy of David Lo, Biomedical
Sciences Dept. UC Riverside, CA
7
Selective Uptake by Mucosal Epithelium
  • However, another research analysis has been
    conducted with nanoparticles, such as Polystyrene
    latex beads and similar bacterial strains with
    varying physiochemical properties in order to
    induce the uptake by M-cells 1.
  • Results of particles treated in PBS buffer at
    physiological pH showed
  • Polystyrene latex beads
  • showed highest ?-potential
  • approximately -107.9 mV
  • S. Aureus showed ?-
  • potential around -31 mV
  • Y. Enterolitica had ?-potential
  • around -19 mV

7
1 Kaila Bennett , Bioengineering Dept. UC
Riverside, CA 2009
8
Experimental Rationale
  • Given some insight into electrostatic interaction
    between bacteria and mucosal epithelia, our
    research group aims to explore the electrostatic
    properties of M-cells
  • Use streaming potential to relate to
    electrostatic properties
  • Develop streaming potential device to determine
    values for M-cell cultured on membranes
  • Compare device performance for protein loaded
    membranes in literature

9
Objectives
  • Test the streaming potential measuring device for
    integrity with protein loaded on PES and CRC
    membranes
  • Observe and collect data of streaming potential
    values to compare the results with preliminary
    studies
  • Calculate zeta potential (?-potential) of protein
    loaded membranes using Helmholtz-Smoluchowski
    equation
  • Modify the streaming potential measuring device
    for electrostatic analysis of intestinal
    epithelia
  • Measure zeta potential of M-cells in intestinal
    mucosal epithelia

10
Common Factors Considered in Electrostatic
Analysis
  • pH
  • Ionic strength
  • Zeta potential
  • Electrostatic potential distribution

11
Schematic Diagram of the Streaming Potential
Device
Courtesy of Yiheng Wang, Bioengineering Dept. UC
Riverside, CA 2008
12
Membranes used in electrostatic test
  • 30 kDa composite regenerated cellulose membrane
    (CRC)
  • not charged
  • not affected by pH
  • Courtesy of Yiheng Wang, UCR, 2008
  • 30 kDa polyethersulfone (PES)
  • negatively charged at most pH conditions

13
Experimental Materials and Methods
  • Set up of the streaming potential device
  • Protein coated membranes are put in the middle of
    the device

14
Data Collection
  • A piece of each CRC and PES membranes was soaked
    in Bovine Serum Albumin solution (BSA) solution
    and in nanopure water overnight prior to test
  • A protein loaded membrane was put into the device
    for the streaming potential test
  • Changing streaming potential was recorded with
    the changing hydraulic pressure applied on the
    device
  • Zeta potential was calculated

15
?-Potential
  • ?-Potential was calculated through Helmholtz
    Smoluchowski
  • equation1
  • e0 - Permittivity of free space
  • er - Relative dielectric constant of the solvent
  • µ - Viscosity of the solution
  • ?0 - Conductivity of the electrolyte solution

1 Nystrom et al. E.Streaming Potential as a
tool in the characterization of ultrafiltration
membranes. Colloids and Surfaces 1989, 36, 297-312
16
Zeta Potential Results and Analysis
Membrane Coating ?-potential (mV) pH 7.0 ?-potential (mV) pH 4.7 ?-potential (mV) pH 10
CRC BSANaCl 19 5.86 8.6 0.83 _______
CRC BSAH2O 2.3 0.46 _______ 9.2 8.15
PES BSANaCl 30 19.04 16 1.46 _______
PES BSAH2O 11 5.13 _______ 23 6.48
17
Comparison to Preliminary Study Analysis
Yiineg Wang, Bioenginering Department, UC
Riverside CA
18
Conclusion
  • The test for the device integrity came out
    successful
  • Expected approximate values and readings were
    obtained in order to calculate zeta potential
  •  

19
Future Agenda
  • Modifying and integrating the streaming potential
    device and methods in order to test zeta
    potential values of cultured intestinal mucosal
    epithelia

Growing Caco2 cell culture from stomach mucosa
Courtesy of Lo, David Biomedical Science Dept. UC
Riverside, CA 2009
20
Acknowledgements
  • NSF
  • Dr. Victor G. J. Rodgers
  • Dr. David Lo
  • Mr. Devin McBride
  • Ms. Kaila Bennett
  • The B2K Group
  • Mr. Jun Wang
  • BRITE REU 2009 Personnel
About PowerShow.com