Focused ultrasound (FUS) can temporarily increase blood-brain barrier (BBB) permeability and locally deliver therapeutic agents to the brain. To date, applications of FUS for treatment of Alzheimer’s disease (AD) have not been explored. Here, I propose that FUS can facilitate a rapid reduction in amyloid-β peptide (Aβ) pathology in a mouse model of AD. Firstly, FUS was used to enhance delivery of an antibody directed against Aβ, which aggregates and forms extracellular plaques. FUS mediated the delivery of antibodies to the targeted right cortex by 4 hours post-treatment and antibodies remained bound to Aβ plaques for 4 days. At 4 days post-treatment, stereological quantification of plaque burden demonstrated a significant reduction of 23%. Secondly, FUS treatment alone resulted in a significant reduction in plaque load (13%). I then investigated effects of FUS that may contribute to Aβ plaque reduction, specifically the delivery of endogenous antibodies to the brain and, activation of microglia and astrocytes. Endogenous immunoglobulin was found bound to plaques within the treated cortex at 4 days post-FUS. Western blot analysis confirmed that immunoglobulin levels were increased significantly. Further, FUS led to a time-dependent increase in glial response. The expression of ionized calcium-binding adaptor molecule 1, a marker of phagocytic microglia, was increased at 4 hours and 4 days, and it was resolved by 15 days. Astrocytes had a slightly delayed response, with an increase in the expression of glial fibrillary acidic protein at 4 days, which declined by 15 days. After 4 days, microglia and astrocytes had significantly greater volumes and surface areas, signifying enhanced activation in the FUS-treated cortex, without an apparent increase in cell count. Co-localization of Aβ within activated glia revealed a significant increase in Aβ internalization following FUS. In conclusion, it was demonstrated that the delivery of exogenous antibodies by FUS, and FUS alone can lead to plaque reduction. Mechanisms by which FUS alone reduces plaque load may include entry of endogenous antibodies to the brain and the induction of a transient glial response. This work details acute effects of FUS that highlight the promise of this delivery method for AD treatment.

Group A streptococcal disorders can result from autoantibodies generated against M proteins. These autoantibodies cross react with the basal ganglia resulting in movement disorders. Previously, we demonstrated binding of streptococcal mAb10F5, with CPu and phospholipids. To determine if mAb10F5 binding to basal ganglia and phospholipids is due to virulence of the antibody or antibody subtype, rats were injected with control IgG2 antibodies and euthanized after 24, 48, or 72 hours. Brains were harvested and immunofluorescence was used to analyze brain slices. Control IgG2 rats showed significantly less fluorescence in the CPu than mAb10F5 injected rats at every time point. These findings reaffirm 10F5 is an anti-basal ganglia antibody. To evaluate mechanism of antibody entry, mAb10F5 was examined for anti-phospholipid activity. MAb10F5 displayed greater affinity to phospholipids when compared to IgG2 controls. Our findings support mAb10F5 is an anti-basal ganglia and anti-phospholipid antibody due to its own virulence. / Access to thesis permanently restricted to Ball State community only / Department of Physiology and Health Science

Previous data in our lab demonstrated an inability to induce oral tolerance when using a feeding needle gavage for 14 days. Given that the upper gastrointestinal (GI) tract is the site of antigen introduction, and the interplay between immune cells of the mucosal tissues, we questioned if inflammation in this tissue, induced by physical trauma, would affect oral tolerance induction. We performed studies on Balb/c mice using a needle gavage or syringe feeding method followed by doses of the immunogenic protein ovalbumin (OVA) to induce tolerance. Immunohistochemistry was used to assess inflammation in esophageal tissues and to correlate with an ability or inability to induce tolerance. Non-cellular alterations within the tissue were also assessed using a pathology grading score. Although fluctuations in cell populations were observed in both the syringe and gavage treated mice, the needle gavage caused significant noncellular damage to esophageal mucosal tissue, which is the most likely cause of failed tolerance induction to the OVA. / Department of Biology

Autoantibodies generated against M proteins can cause post-streptococcal disorders such as Rheumatic Fever. A severe complication of rheumatic fever is rheumatic heart disease which may involve both cardiomyopathy and valvulitis. Rheumatic fever has been associated with the class I M protein epitope of Group A streptococcus (GAS). This epitope can be recognized by monoclonal antibodies (mAbs) 10B6 and 10F5. Previously, we demonstrated binding of streptococcal mAb10F5 in the heart tissue (apex, atria, and valves) of Lewis rats as compared to anti-myosin binding. To determine if mAb10F5 binding in the heart is due to virulence of the antibody or antibody subtype, rats were injected with control IgG2 antibodies and euthanized after 24, 48, or 72 hrs. Hearts were harvested and immunofluorescence was used to analyze the hearts. The immunofluorescence intensities for IgG2b were compared to mAb10F5 using previously acquired data. Control IgG2b rats showed significantly less immunofluorescence intensities in the heart regions than mAb10F5 injected rats at the 48 and 72 hr time points. These findings reaffirm mAb10F5 as an anti-cardiac antibody thatbinds heart tissue due its own virulence. To differentiate between the two IgG subtypes, binding intensities of IgG2a were compared to the binding intensities of IgG2b. The binding intensities of IgG2a increased with time. This finding was supported by previous work in our laboratory suggesting IgG2a remained in the bloodstream longer than the IgG2b. / Access to thesis permanently restricted to Ball State community only. / Department of Physiology and Health Science

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Linköping : Univ., 2002. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 6 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.