Trial Information

Eosinophil Activation and Function in Parasitic Infections and Other Conditions With Increased Tissue or Peripheral Blood Eosinophilia in Humans

Subjects admitted on this protocol will have elevated eosinophil counts in the peripheral
blood or tissues or will be relatives of subjects with eosinophilia. Eosinophilic subjects
will undergo an extensive clinical evaluation focused on the identification of the cause of
eosinophilia and the presence of end organ manifestations. In addition, they will be
characterized in detail immunologically, and their blood cells and/or serum will be
collected to provide reagents (eg. specific antibodies, T-cell clones, etc.) that will be
used in the laboratory to address broader questions relating to the etiology of
eosinophilia, its immunoregulation, the degree and source of eosinophil activation, and/or
the functional role of eosinophils in the afferent arm of those immune response where they
are prominent. While the protocol is not primarily designed to study treatment of patients
with blood and tissue eosinophilia, the clinical and immunological responses to various
medically indicated therapies will be carefully monitored. The subjects themselves will be
followed over time to determine the kinetics and nature of the factors affecting their
degree of eosinophilia and the level of activation or degranulation of the eosinophils at
various time points and in response to various stimuli. It is anticipated that the subjects
will receive a degree of clinical evaluation, care and monitoring more extensive than that
generally available and that the specimens collected from them will prove to be valuable
reagents for laboratory studies related to eosinophilia, eosinophil activation and function.
Recognized causes of subjects' hypereosinophilia will be treated appropriately either by our
own clinical service or by the referring physicians. Experimental chemotherapy in this
protocol is restricted to that administered under special exemption status. This protocol
will also allow clinical and laboratory evaluation of family members of subjects with
eosinophilia in order to help identify genetic causes of eosinophila and to provide controls
for immunologic studies.