RETINOIC ACID AND ALPHA-GALACTOSYLCERAMIDE AFFECT EXPRESSION OF SELECTED B CELL SURFACE MARKERS IN VITRO AND THE ANTIBODY RESPONSE IN VIVO
Open Access
- Author:
- Mosovsky, Kara Lee
- Area of Honors:
- Immunology and Infectious Disease
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Dr. A. Catharine Ross, Thesis Supervisor
Dr. A. Catharine Ross, Thesis Supervisor
James Endres Howell, Thesis Honors Advisor - Keywords:
- retinoic acid
B cell
alpha-galactosylceramide
antibody response - Abstract:
- Retinoic acid (RA) and α-Galactosylceramide (GalCer) have been shown to have diverse stimulating effects on the immune system. They have both been shown to promote Th2 differentiation, increase antibody responses, as well as alter cytokine production from various immune cells. In addition, both compounds have been shown to affect B cell differentiation either directly (RA) or indirectly through iNKT cell activation (α-GalCer). The current study was designed to determine if RA and α-GalCer could regulate immunity by targeting costimulatory and accessory molecules on the surface of the B cell. The hypothesis of this thesis is that RA and α-GalCer will regulate immunity by increasing expression of accessory and costimulatory molecule expression on the surface of B cells. Splenic B cells were cultured with various combinations of RA, α-GalCer, and anti-μ treatments in order to stimulate naïve and resting B cells. Expression of differentiation and activation markers, mainly costimulatory molecules and isotype-switched immunoglobulin, were analyzed by flow cytometry analysis at different time points after treatment addition. Furthermore, CD1d-/- mice were used to determine whether the enhancing effects of α-GalCer, seen in vitro for B cell surface marker expression and in vivo for the anti-tetanus antibody response, were dependent on CD1d. Therefore, experiments compared WT and CD1d-/- responses to the aforementioned in vitro treatments as well as in an in vivo tetanus toxoid (TT) immunization study with RA and α-GalCer treatments. The in vitro treatment results suggest that RA+ α-GalCer may prime B cells for enhanced immune response to antigen stimulation through increases in CD19hi and IgDhi populations as well as almost a 4 fold increase in CD86 expression. It was also shown that NKT cells do not significantly contribute to the anti-tetanus antibody response in vivo. In addition, good evidence was provided that the α-GalCer effect of enhanced IgG response to TT immunization is dependent on CD1d expression.