Effects of Secondary Forces on the Primary Interaction and Variable Domain Conformation of Antifluorescein Antibodies

234 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997.Secondary forces are biochemical interactions that occur between regions surrounding the mouth of the antibody active site and the environment of homologous ligand or epitope. These interactions have been demonstrated to modulate the antibody variable domains as well as impacting complex stability. Although secondary forces do not dictate antibody specificity (the primary interaction) an understanding of these interactions is critical in evaluating the nuances of antibody/antigen interactions. Described within this thesis is a series of biophysical measurements that have allowed the delineation and quantitation of secondary forces. These are the first experiments to convincingly separate primary interactive components from secondary interactive components. This dissection of primary from secondary forces was made possible by the utilization of the monoclonal antifluorescein antibody system. Fluorescein has been shown to be an active site-filling moiety. Fluorescein 5-isothiocyanate was covalently linked to the $\varepsilon$-amine of lysine residues in proteins or synthetic peptides. Differences in the binding reactivity and various spectral parameters of a series of monoclonal antifluorescein antibodies were compared and contrasted when bound with fluorescein and fluorescein conjugated to unique physical and chemical topolgies. Since the active site was completely filled by the fluorescyl moiety, differences in measured properties was a consequence of attached residues that composed the carrier environment. Three monoclonal antifluorescein antibodies (mAbs) were utilized for these studies (4-4-20, 9-40 and 18-2-3). This panel of antibodies was chosen due to the high degree with which they have been characterized biochemically and biophysically. Differential effects due to secondary forces were correlated with known properties of these antibodies. Moreover, these antibodies were compared and contrasted with one another. Models employing variable domain dynamics were developed to explain results from the various experiments and were correlated with known structural and chemical information regarding these antibodies.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Psychological Stress and the Cutaneous Immune Response: Roles of the HPA Axis and the Sympathetic Nervous System in Atopic Dermatitis and Psoriasis

Psychological stress, an evolutionary adaptation to the fight-or-flight response, triggers a number of physiological responses that can be deleterious under some circumstances. Stress signals activate the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system. Elements derived from those systems (e.g., cortisol, catecholamines and neuropeptides) can impact the immune system and possible disease states. Skin provides a first line of defense against many environmental insults. A number of investigations have indicated that the skin is especially sensitive to psychological stress, and experimental evidence shows that the cutaneous innate and adaptive immune systems are affected by stressors. For example, psychological stress has been shown to reduce recovery time of the stratum corneum barrier after its removal (innate immunity) and alters antigen presentation by epidermal Langerhans cells (adaptive immunity). Moreover, psychological stress may trigger or exacerbate immune mediated dermatological disorders. Understanding how the activity of the psyche-nervous -immune system axis impinges on skin diseases may facilitate coordinated treatment strategies between dermatologists and psychiatrists. Herein, we will review the roles of the HPA axis and the sympathetic nervous system on the cutaneous immune response. We will selectively highlight how the interplay between psychological stress and the immune system affects atopic dermatitis and psoriasis