Viruses are common causative agents of ocular infection among humans. Epidemic keratoconjuntivitis (EKC) is a severe and contagious ocular disease with reported outbreaks worldwide. It is estimated that this disease affects 20-40 million individuals every year, which leads to huge socioeconomic costs for the affected countries. EKC is characterized by keratitis and conjunctivitis but is also associated with pain, edema, lacrimation, and decreased vision that can prolong for months after the infection and in rare cases years. This disease is caused by human adenoviruses (HAdVs), which belong to the family of Adenoviridae. Currently, there is no available treatment against EKC. EKC is mainly caused by HAdV-8, HAdV-19, HAdV-37, HAdV-53, HAdV-54, and HAdV-56, which belong to species D HAdVs. HAdV-8, HAdV-19 and HAdV-37 have previously been shown to use sialic acid (SA)-containing glycans as cellular receptors to bind to and infect human corneal epithelial (HCE) cells. To characterize the receptor in more detail, we performed a glycan array, which included SA-containing glycans. A branched hexasaccharide terminating with SA in each arm was identified as a candidate receptor. This glycan corresponds to the glycan motif found on a ganglioside, GD1a. By performing a series of biological and biochemical experiments we confirmed the function of the GD1a glycan as a cellular receptor for EKC-causing HAdVs. However, the glycan used as a receptor was linked to plasma membrane protein(s) through O-glycosidic bonds, rather than to a lipid (as in the ganglioside). X-ray crystallography analysis showed that the two terminal SA:s interacted with two of the three previously identified SA-binding sites on the knob domain of the HAdV-37 capsid protein known as the fiber. Based on the structural features of the GD1a:HAdV-37 knob interaction, we assumed that a three-armed molecule with each arm terminating with SA would be an efficient inhibitor. Such molecules were designed, synthesized and found to efficiently prevent HAdV-37 binding to and infection of corneal cells. These results indicate that trisialic acids-containing compounds may be used for treatment of EKC. After binding to its primary receptor, most HAdVs have been shown to interact with αVβ3 and αVβ5 integrins to enter human cells. This interaction occurs through the RGD (arginine-alanine-aspartic acid) motif in the capsid protein known as the penton base. However, it was not clear if corneal epithelial cells express αVβ3 and αVβ5 integrins. Thus, to better understand additional early steps of infection by EKC-causing HAdVs, we performed binding and infection competition experiments using human corneal epithelial cells and siRNA, integrin specific antibodies, peptides and RGD-containing ligands indicating that α3, αV, β1 affected HAdV-37 infection of but not binding to HCE cells. We could also see that HAdV-37 co-localize with α3 and αV at after entry into HCE cells. In situ histochemistry confirmed that the expression of α3 and αV in human corneal tissue. Overall, our results suggest that αV and α3 integrins are important for HAdV-37 infection of corneal cells. Altogether, these results provide further insight into the biology of HAdVs and open up for development of novel antiviral drugs.

Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

Circulating neutrophil activation occurs during cardiac surgery with extracorporeal circulation (ECC) and is implicated in the pathophysiology of inflammatory tissue injury and peri-operative organ dysfunction. However, neutrophil directed antiinflammatory strategies have failed to demonstrate consistent therapeutic benefit indicating that the nature and significance of peri-operative circulating neutrophil activation remains incompletely defined. In particular, conformational activation of the b2 integrin Mac-1 (CD11b/CD18), which is required for neutrophil adhesion competence and facilitation of effector functions, has not previously been investigated during cardiac surgery, and the relative contribution of cellular activation and bone marrow neutrophil recruitment to peri-operative changes in circulating neutrophil phenotype and function is unknown. A novel whole blood flow cytometric technique was used to analyze circulating neutrophil phenotype (total Mac-1, conformationally-active CD11b, CD10, CD16, L-selectin and P-selectin glycoprotein ligand-1) and function in cardiac surgery patients to characterize the nature of changes in Mac-1 expression and activation status, and the effects of relative neutrophil immaturity on circulating neutrophil phenotype and function. The effect of heparin, a known CD11b ligand, on Mac-1 epitope expression was also investigated. Circulating neutrophil numbers observed during ECC were mathematically modeled to determine the acute response of the bone marrow neutrophil reserve to an inflammatory stimulus. Plasma cytokine, chemokine and acute phase mediators were measured in cardiac and lung surgery patients to determine potential regulators of systemic neutrophil recruitment. Neutrophils newlyemergent from the bone marrow were characterized as CD10-/CD16low and exhibited distinct changes in cell surface markers and enhanced functional responses, relative to their more mature CD10+ counterparts. Conformational activation of CD11b occurred peri-operatively and provided a more sensitive measure of circulating neutrophil activation status than changes in total Mac-1 or L-selectin expression, although detection of Mac-1 epitopes was reduced in the presence of heparin. Modeling of circulating neutrophil numbers predicted that post-mitotic maturation time was acutely abbreviated by 8.4 hours during 71 minutes of ECC. Systemic chemokine release occurred with cardiac but not non-cardiac thoracic surgery indicating some specificity of the acute inflammatory response. These findings expand the understanding of peri-operative circulating neutrophil activation and recruitment, and identify potential therapeutic targets to limit neutrophil injurious potential during cardiac surgery with ECC.

Copy of author's previously published article in pocket on back end-paper. / Includes bibliography (leaves 135-185). / 185, [94] leaves, [32] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Aims to characterise the expression of PETA-3 (Platelet Endothelial Tetraspan Antigen-3), CD9, CD63 and ?gb?s1 integrins in normal human tissue ; to determine the subcellular localisation in endothilial cells and platelets ; to investigate protein-protein interactions involving PETA-3 ; and to examine the effects of anti-PETA-3 monoclonial antibodies on platelet and endothilial cell function. / Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine, 1999

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [82]-96).

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [134]-154).

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 52-68).

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 160-166). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 160-166). Also available on the Internet.