Monoclonal antibodies which recognise tumour-associated antigens provide a means of targeting radionuclides selectively to tumour cells. (^99m)Tc and (^64)Cu are potentially useful isotopes for radioimmunoimaging;(^ 90)Y and (^67)Cu may be suitable for radioimmunotherapy. The synthesis of functionalised macrocycles for binding these four radioisotopes to antibodies is described. In each case, a macrocycle has been selected to provide a complex which is kinetically inert, thereby preventing dissociation of the radiolabel in vivo. A novel strategy for conjugating a C-alkylated cyclam derivative (for binding Tc and Cu) to an antibody is described. This method facilitates the selective acylation of an exocyclic primary amino group in the presence of the secondary ring nitrogens. Unfortunately, the labelling of antibody-bound cyclam with (^99m)Tc required conditions (pH 11) which produced extensive binding of the radiolabel to the protein backbone. "Non-specific" (^99m) Tc was subsequently found to dissociate in vivo. Pre-labelling the macrocycle with (^99m)Tc solved the "non-specifics" problem but required a pH which meant that the conjugation step was too slow for sufficient specific activity to be bound. A phenol-pendent derivative of cyclam was found to incorporate (^99m)Tc at a lower pH than cyclam itself. The "non-specific" binding of copper to the protein was minimised using a low pH labelling strategy in conjunction with a chelate wash. Macrocycle antibody conjugates labelled manner provide very promising biodistribution profiles in normal mice. A labelling buffer was selected to enhance the rate of uptake of copper by the macrocycle at low pH. Macrocycle-antibody conjugates containing 13N(_4), which was found to provide faster association kinetics than cyclam, have been prepared and await radiolabelling studies. A derivative of I3N(_4), containing 4 carboxylic acid donor sites, has been functionalised for conjugation to an antibody to act as a (^90)Y binder.

No description available.

Thesis (Ph. D.)--University of New South Wales, 1999. / Also available online.

Thesis (Ph.D.)--Virginia Commonwealth University, 2008. / Title from title-page of electronic thesis. Prepared for: Dept. of Pharmaceutics. Bibliography: leaves 149-166.

Thesis (M.A.)--Central Connecticut State University, 2004. / Thesis advisor: Kathy Martin. " ... in partial fulfillment of the requirements for the degree of Master of Arts in Biological Sciences." Includes bibliographical references (leaf 36). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Chicago, Committee on Immunology, June 1997. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph.D.)--York University, 2008. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 243-264). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR51693

The causative agent of the most deadly form of malaria, P. falciparum, was identified over 130 years ago, yet this disease still causes 430,000 deaths each year. Although naturally-acquired immunity exists, it requires a heavy and sustained exposure to the parasite, with most succumbing as young children, before this immunity has fully developed. Effective treatments exist but with small-molecule drug resistance on the rise and little in the way of affordable alternatives, the need for an efficacious malaria vaccine is as great as ever. A successful malaria vaccine is likely to necessitate targeting each stage of the parasite's lifecycle. Immunity directed to the blood-stage, the stage which causes all the symptoms of malaria, is unique in that it would allow for a concomitant development of naturally-acquired immunity along with a reduction in morbidity and mortality. To date, antibody-mediated immunity to the blood stage requires intractably high levels of antibody and this problem is compounded by a paucity of viable candidates with which to effectively target different strains. Other fields of vaccinology, over the past decade, have been employing various structure-based strategies to increase the specific activity of the immune response thus lowering the antibody levels required for protection. However, very few detailed investigations of this kind have been conducted on a P. falciparum vaccine candidate, and certainly none as promising as PfRH5. In a world's first, fully-human antibodies raised in response to PfRH5 vaccination were isolated and extensively characterised, both functionally and structurally with the intention of elucidating the important features necessary to inform the design of an improved PfRH5-based vaccine. Synergistic and antagonistic effects of antibody combinations were noted and highlight new complexities of the immune response to PfRH5, opening the door to unanticipated potential for rational vaccine design.

Made available in DSpace on 2014-06-11T19:23:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T20:50:03Z : No. of bitstreams: 1 cardoso_ra_me_botfm.pdf: 896730 bytes, checksum: 97ac1a0ea8e45d9861c31c7feaac2ecb (MD5) / Fundação para o Desenvolvimento Médico e Hospitalar (Famesp) / A tecnologia de produção de anticorpos monoclonais revolucionou a investigação diagnóstica, especialmente a análise dos grupos sanguíneos em imuno-hematologia. O polimorfismo das hemácias humanas torna a produção de novos insumos extremamente necessária. Dentre os sistemas de grupos sanguíneos descritos, o sistema Rh tem se mostrado um dos mais complexos pela vasta composição de antígenos. Analisando aspectos estruturais do antígeno D associado às técnicas de biologia molecular, identificam-se numerosas variantes deste antígeno por trocas de DNA entre genes similares levando a alteração de epítopos e consequentemente de padrão de expressão fenotípica na superfície das hemácias. Desvendar e identificar estas variantes com insumos biotecnológicos desenvolvidos no país foi o desafio desta pesquisa, onde anticorpos monoclonais contra antígenos eritrocitários foram produzidos através de fusão celular, utilizando-se células de baço de camundongos BALB/c imunizados com hemácias fenótipo D categoria IVa. Nove fusões foram realizadas e os sobrenadantes de cultura foram triados por teste de hemaglutinação em microplacas. Foram congelados e mantidos em nitrogêncio líquido 41 híbridos. Estes híbridos foram clonados e mantidos em meio de cultura para a obtenção dos anticorpos monoclonais, resultando em 12 clones IgG1, 5 IgG2a e 10 IgM. Os clones foram selecionados para produção de líquido ascítico, através da injeção dos clones em camundongos BALB/c. Os anticorpos monoclonais produzidos, inicialmente não demonstraram a especificidade foco do presente trabalho que foi a produção de anticorpos anti-D, no entanto, os hibridomas podem ter secretado diferentes especificidades de anticorpos monoclonais, de acordo com os antígenos presentes na membrana das hemácias utilizadas para a imunização dos camundongos. Uma segunda fase da pesquisa está sendo... / The blood groups analyses in immunohematology have been highly benefited based on the advance of the monoclonal antibody technology improvement on diagnostics investigation. The human red blood cell polymorphism increases the need for new alternatives. The Rh system blood group is the most complex of all, due to the vast antigenic composition. When analyzing the structural aspects of the D antigen in combination with the molecular techniques, based upon DNA exchange between similar genes it is possible to identify a huge number of partial D variants, this situation leads to a change of epitopes and hence the red blood cell phenotypic expression pattern. Unveil and identify these variables through the use of local biotechnology was the challenge of this research. Monoclonal antibodies against human red blood cell were produced by cell fusion, using spleen cells from immunized BALB/c mice and DIVa red blood cells. Nine fusions had been made and the culture supernatants were selected to the hemaglutination test using microplates. Forty-one hybrids had been frozen and kept in liquid nitrogen. These hybrids had been cloned and kept in the culture to collect monoclonal antibodies, resulting in 12 IgG1, 5 IgG2a e 10 IgM. The clones had been selected for ascitic fluid production, by injection in BALB/c mice. The monoclonal antibodies produced initially had not produced the anti-D as expected by the research. However, the hibrydomas could have created different specificities of monoclonal antibodies, according to the antigen located in the donor red blood cells membrane used in the mice’s immunization. The second phase of the research is being done to confirm the monoclonal antibodies specificities produced through the deployment of new tests to immunoglobulin identification

Guillain Barré Syndrome in humans is characterised by ascending paralysis. It is often associated with preceding infections two to four weeks prior to nadir and is fatal in five percent of cases. Antibodies specific to several nerve components are frequently associated with clinical symptoms in GBS. These antibodies were found to be specific to various gangliosides and ganglioside complexes. It was also found that antibody reactivity to gangliosides is affected by membrane components. The most prevalent (20-30%) immunoglobulin in GBS is anti-GM1 (20-30%), which also binds to the LPS of the PEN O:19 Campylobacter jejuni serotype. This is the most common infectious agent associated with GBS and emphasizes the importance of infection and anti-ganglioside antibodies in disease development. Intravenous infusion of pooled immunoglobulin from healthy donors, also called intravenous immunoglobulin (IVIg), halves the severity of disease manifestation. The action mechanism of IVIg in curing GBS is not clear, but intravenous immunoglobulin was shown to neutralize anti-ganglioside binding activity and its pathogenic effects. It was further found that anti-idiotypic antibodies in IVIg inhibit anti-ganglioside antibody activity. Treatment with IVIg is not equally effective in all GBS cases, which might be due to the inability of IVIg to neutralize anti-ganglioside antibodies in all patients adequately. Therefore, the treatment of GBS with IVIg needs to be better understood in order to improve its use as a cure for GBS. This study confirmed previous findings that the interaction of patient serum anti-GM1 antibodies and ganglioside auto-antigens is greatly impaired by components in healthy serum. Bound anti-GM1 antibodies could be displaced by (presumably) anti-idiotypic antibodies from healthy donor serum. This study found that the displacement potential between donor sera differs. Anti-GM1 antibody displacement was found to be dependent on the character of both anti-GM1 and anti-idiotypic antibody. This demonstrated the feasibility of improving the efficiency of treatment by IVIg by sourcing it from only those sera that test best for displacing auto-antibodies from their ganglioside antigens in ELISA. IVIg selection may therefore greatly benefit from the use of recombinant phage display antibodies to distinguish between the various types of GBS for treatment. To develop a method to characterize anti-ganglioside antibodies sensitively, an evanescent field biosensor was employed in which gangliosides were presented in a liposome environment. This provided a more physiological way of antibody antigen recognition. The optimized method determined the ganglioside binding specificity of purified IgG from a GBS patient, and mouse monoclonal anti-GM1 and anti-GD1a antibodies accurately. The results compared well with those from ELISA. The results obtained with purified IgG were far better than that obtained with whole serum analysis. This could be due to non-specific binding or the presence of inhibiting anti-idiotypic antibodies in patient sera. The biosensor method for antibody detection in GBS may allow the detection of anti-idiotypic antibodies in patients in future, because it requires no prior labelling of antibodies. Anti-idiotypic interaction may be detected by displacement of Ab1 from antigen, or by capturing Ab2 on Ab1 immobilized on the biosensor surface. / Dissertation (MSc (Biochemistry))--University of Pretoria, 2008. / Biochemistry / MSc / unrestricted