Probing the function of LFA-1 using fluorescent proteins that target the beta-2 integrin transmembrane domain

• Author / Creator

  Ebesoh, Njuacha

• The lymphocyte functional antigen-1 (LFA-1) is a type I heterodimeric transmembrane (TM) proteins involved in cell adhesion, and mediates a number of cellular and physiological processes. In this work, we used recombinant fluorescently-tagged proteins derived from the TM domain of the β2 integrin to disrupt the function of LFA-1 on Jurkat cells. Four variants of the proteins were made including: one with a short cytoplasmic tail (EGFPβ2TM+CD), without the cytoplasmic tail (EGFPβ2TM-CD), truncation of five amino acids (EGFPβ2TM-5B) and truncation of ten amino acid (EGFPβ2TM-10B). These proteins were able to label Jurkat cells in vitro in a protein binding assay with affinity, Kd as high as 280 ± 80 nM (EGFPβ2TM-5B). We used fluosphere beads conjugated to different mAb to study the effect of binding on the epitopes of LFA-1. The proteins had an overall activation effect on MEM148 and an inhibitory effect on MEM48 epitope of LFA-1 receptor.

• Subjects / Keywords

  • LFA-1
  • Binding epitopes
  • Transmembrane protein
  • Monoclonal antibodies
  • Fluosphere beads
  • Beta-2 integrin
  • Flourescent proteins

• Graduation date

  Spring 2011

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3G33C

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.