Effector cells in the immunity to a lethal strain of Babesia microti in absence of the parasite /
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1989.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | The Peabody non-lethal (NL) and a lethal (L) strain of B. microti were studied. Infection of mice with the NL conferred protection against challenge with the L strain as reported by Sharp (1). Cross protection was noted when the NL infection was given at least three hours before L challenge. The effect of inoculation of different numbers of parasites of the two strains of B. microti was evaluated. The efficacy of two common drugs used in the treatment of babesiosis, diaminazene aceturate and imidocarb dipropionate, were tested. Diaminazene aceturate, either as Ganaseg or Berenil, did not have a curative effect against either strain of B. microti when inoculated intramuscularly at the recommended or higher doses. In contrast, imidocarb dipropionate (Imizol) was highly effective against both strains, and was shown to completely abolish infection. When infected Imizol treated mice were immunosuppressed by high doses of dexamethasone, splenectomy or a lethal dose of ionizing radiation, no recrudescence was observed. A sterile cross protective immunity was observed in such mice, lasting for up to three months. However, after three months the mice were again susceptible. Attempts to transfer cross-strain protection to mice infected with L. S. microti with sera from mice which had recovered from the NL infection were unsuccessful as reported by Sharp (1). Attempts to passively transfer this cross-protection with mouse spleen cells were also unsuccessful. Cross-strain protection was also completely resistant to dexamethasone treatment and to lethal irradiation. Vaccination with an attenuated strain of Mycobacterium tuberculosis (BCG) by the subcutaneous or intravenous routes did not confer any protection against the L strain although it showed moderate protection against the NL. Intravenous and intraperitoneal inoculation of mice with endotoxin from S. typhimurium prior to L challenge delayed the onset of parasitemia. Endotoxin inoculation during L infection did not have any protective effect even in BCG vaccinated mice. Infection with L B. microti completely suppressed delayed type hypersensitivity to purified protein derivative (PPD) in BCG vaccinated animals. The antibody response to sheep red blood cells was also suppressed... |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Veterinary microbiology." |
| Physical Description: | xiii, 155 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |