Interleukin-5 receptors on human lung eosinophils after segmental allergen challenge.

BACKGROUND: IL-5 is a specific cytokine for eosinophil accumulation, activation and prolongation of survival and can be recovered in elevated concentrations from the bronchoalveolar compartment in atopic asthma following allergen challenge. OBJECTIVE: The action of IL-5 is mediated via the specific IL-5 receptor-alpha (IL-5Ralpha). Although in vitro data suggest that IL-5R expression is regulated by cytokines such as IL-3, IL-5 and GM-CSF, IL-5R regulation in vivo and its kinetics following allergen provocation are incompletely understood. METHODS: We investigated IL-5R regulation in vivo following segmental allergen provocation (SAP) with an individually standardized dose of allergen in 12 patients with atopic asthma. Lavage was performed 10 min and 18 h (eight patients) and 10 min and 42 h (eight patients) after allergen challenge. In addition to differential cell counts, IL-5Ralpha was measured by flow cytometry and IL-5 concentrations in bronchoalveolar lavage (BAL) fluid were determined by ELISA. RESULTS: IL-5Ralpha expression decreased significantly on peripheral blood and on BAL eosinophils 18 and 42 h after SAP. In contrast, IL-5 concentrations increased significantly in BAL fluid 18 and 42 h after SAP. In four and two patients, respectively, there were detectable IL-5 concentrations in serum 18 or 42 h after allergen exposure. CONCLUSIONS: Although there was no correlation between IL-5 concentrations and IL-5Ralpha expression on eosinophils in BAL, our data support previous in vitro and in vivo findings of a negative feedback mechanism between IL-5 concentrations and IL-5Ralpha expression on eosinophils.

Training agrammatic subjects on passive sentences: implications for syntactic deficit theories.

We trained two subjects with chronic agrammatic aphasia on production of passive sentences using a computerized, iconic-based communication system. After training, one of the subjects demonstrated significant improvements in his abilities to comprehend and verbally produce English passive voiced sentences, including sentences with conjoined subjects and objects. These results suggest that agrammatism does not represent a fixed syntactic deficit.

Maintenance of oral production in agrammatic aphasia: verb tense morphology training.

We used a single-subject research design to examine long-term maintenance of treatment gains in a severely aphasic patient. We used a well-defined therapy protocol [i.e., Computerized Visual Communication System (C-VIC) training] to target production of tense morphology and an assessment specifically designed to measure improvements in the targeted behavior. We first trained Subject #1, a 65-year-old man with a severe nonfluent aphasia, to produce simple subject-verb-object sentences, then tense-marked sentences. Remarkable improvement was shown and was maintained five months after training was terminated. Sixteen months later, he maintained only the ability to produce trained root verb forms. A second training was initiated to examine the parameters of training that affect maintenance. Maintenance was demonstrated up to a year after termination of treatment. We attribute Subject #1's maintained performance to his continued involvement in general C-VIC sentence level therapy following tense training.

Representation of linguistic rules in the brain: evidence from training an aphasic patient to produce past tense verb morphology.

We trained a patient with expressive aphasia and a deficit in phoneme-to-grapheme conversion to produce spoken English verbs with correct tense morphology. After training, he showed evidence of generalization to production of written regular, but not irregular, verbs in a sentence completion task. These data support dual-route, rule-based models within the brain for morphosyntactic operations.