Laboratory animal science最新文献

Background and purpose: Murine ascites production has been associated with appreciable morbidity and mortality, thus raising animal-welfare concerns. To address these concerns, the clinicopathologic changes associated with in vivo production of monoclonal antibodies in mice were characterized, and results were compared among cell lines.

Methods: Five hybridoma cell lines were grown in groups of 20 mice. Fourteen days prior to inoculation with 10(6) hybridoma cells, mice were primed with 0.5 ml of pristane given intraperitoneally; 12 mice were sham treated (controls). Ascites fluid was collected a maximum of three times by abdominal paracentesis. Clinical observations and pre- and postabdominal tap body weights were recorded. Necropsies were performed on all mice.

Results: For all groups combined, overall survival to tap 1 was 98%, to tap 2 was 96%, and to tap 3 was 79%; survival among groups ranged from 90 to 100% for tap 1, 85 to 100% for tap 2, and 35 to 100% for tap 3. Disseminated intra-abdominal seeding with irregular soft tissue and/or solid tumor masses was observed at necropsy.

Conclusions: Significant clinicopathologic changes were associated with monoclonal antibody production in mice, and differences between various hybridoma cell lines were apparent.

Background and purpose: A measles outbreak in a facility housing Old World nonhuman primates developed over a 2-month period in 1996, providing an opportunity to study the epidemiology of this highly infectious disease in an animal-handling setting.

Methods: Serum and urine specimens were collected from monkeys housed in the room where the initial measles cases were identified, other monkeys with suspicious measles-like signs, and employees working in the affected areas. Serum specimens were tested for measles virus-specific IgG and IgM antibodies, and urine specimens were tested for measles virus by virus isolation or reverse transcriptase-polymerase chain reaction (RT-PCR).

Results: A total of 94 monkeys in two separate facilities had evidence of an acute measles infection. The outbreak was caused by a wild-type virus that had been associated with recent human cases of acute measles in the United States; however, an investigation was unable to identify the original source of the outbreak. Quarantine and massive vaccination helped to control further spread of infection.

Conclusions: Results emphasize the value of having a measles control plan in place that includes a preventive measles vaccination program involving human and nonhuman primates to decrease the likelihood of a facility outbreak.

A single injection of Escherichia coli lipopolysaccharide (LPS; intraperitoneally [i.p.] and intravenously [i.v.]) reliably induces peripheral nerve disturbances in the hindlimbs of inbred Australian albino Wistar (AaW) rats. In the series of experiments presented here, we aimed to characterize this syndrome by examining electrophysiologic, immunologic, and immunochemical features. The LPS-induced neurologic sequelae in AaW rats were transient, at least partly reversible by drug treatment, and were not associated with any detectable neuropathologic findings by light microscopy. Neurologic sequelae were prevented by administration of dexamethasone and by pretreatment with the macrophage inhibitor gadolinium chloride, suggesting that they were caused by LPS-induced activation of peripheral macrophages. Sequelae were associated with early decreases in compound muscle-action potential amplitudes, indicating impaired functioning of either proximal sciatic nerve axons and/or neuromuscular synapses. Spinal somatosensory-evoked potential latencies also were increased, indicating impaired somatosensory function at the sciatic nerve, dorsal roots, spinal cord, and/or postsynaptic interneurons, although the precise location of impairment could not be delineated. Similarities between this syndrome and immune-mediated polyneuropathies in humans are discussed.