Activation and Function of Eosinophils in Conditions With Blood or Tissue Eosinophilia
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT00001406|
Recruitment Status : Recruiting
First Posted : November 4, 1999
Last Update Posted : August 6, 2020
This study will investigate how, why and under what conditions eosinophils (a type of white blood cell) become activated and will examine their function in immune reactions. Eosinophil counts often rise in response to allergies, asthma, and parasitic worm infections. They can also go up in uncommon autoimmune conditions and, rarely, in association with tumors. Elevated levels of these cells is called eosinophilia. Usually, eosinophilia causes no apparent symptoms, but in rare cases there may be local swelling and itching, allergic lung problems, heart disease or nerve damage caused by the release of toxic substances in these cells into body tissues.
Patients 1 to 100 years of age with eosinophil counts greater than 750/ml or an abnormal accumulation of eosinophils in the skin or body tissues may be eligible for this study. All participants will have a thorough medical history, physical examination and blood tests. Depending on the person's age and symptoms, other diagnostic tests may be done, including specialized studies of the eye, lungs, skin, bone marrow, nerves or heart. This is not a treatment study, and no experimental treatments will be offered. Patients who require treatment will receive standard medical care.
Certain other procedures may be requested solely for research purposes. All participants will be asked to donate extra blood for laboratory studies investigating how immune cells and other immune substances in the blood act to stimulate a rise in eosinophils. In addition, some participants may undergo one or more of the following:
- Annual Follow-up evaluations - Physical examinations and blood tests to evaluate changes in the patient's condition and eosinophil counts over time.
- Bone marrow biopsy and aspiration will be recommended during the initial evaluation, and in certain patients at other times when it is important to look directly at the newly developing cells in the bone marrow. For this procedure an area of skin and bone is anesthetized with xylocaine (an anesthetic similar to that used by dentists), and a very sharp needle is used to sample the bone marrow for evaluation. Bone marrow biopsy and aspiration can have side effects of pain and/or bleeding into the skin and soft tissues at the site of the procedure. Rarely the area at the biopsy site can become infected, and is treated with antibiotics.
- Genetic testing: Some of the blood drawn from you as part of this study will be used for genetic tests. Genetic tests can help researchers study how health or illness is passed on to you by your parents or from you to your children. Any genetic information collected or discovered about you or your family will be confidential.
- Leukapheresis (only patients 18 years and older) to collect large numbers of certain cells - In this procedure, whole blood is collected through a needle placed in an arm vein. The blood circulates through a machine that separates it into its components. The white cells are then removed and the rest of the blood is returned to the body, either through the same needle used to draw the blood or through a second needle placed in the other arm.
|Condition or disease|
|Immune System Diseases Eosinophilia Helminthiasis Hypersensitivity Parasitic Disease|
|Study Type :||Observational|
|Estimated Enrollment :||800 participants|
|Official Title:||Eosinophil Activation and Function in Parasitic Infections and Other Conditions With Increased Tissue or Peripheral Blood Eosinophilia in Humans|
|Actual Study Start Date :||April 21, 1997|
Volunteers with elevated eosinophil counts in the peripheral blood or tissues; or a relative of a volunteer with eosinophilia
- Collect data and samples to enhance the understanding of the mechanisms driving eosinophilia and eosinophil activation in patients [ Time Frame: Ongoing assessment ]Greater understanding of the mechanisms driving eosinophilia and eosinophil activationCollect data and samples to enhance the understanding of the mechanisms driving eosinophilia and eosinophil activation in patients with a wide range of eosinophilic disorders with the ultimate goal of improving diagnostics and identifying novel treatment modalities.
- To explore the role of the intestinal microbiome in eosinophilic gastrointestinal inflammation [ Time Frame: Ongoing ]
- To provide information about patient signs and symptoms for use in the development of a patient-related outcomes questionnaire for use in future treatment studies [ Time Frame: 12/31/2020 ]
- To study and identify genetic causes of eosinophilia [ Time Frame: Ongoing ]
- To develop a panel of laboratory and clinical tests that will aid in categorizing various conditions associated with blood and/or tissue eosinophilia and/or in monitoring response to therapy [ Time Frame: Ongoing ]
- To study the role of inflammation associated cytokines/chemokines on the activation of eosinophils and their recruitment to the blood and tissues [ Time Frame: Ongoing ]
- To evaluate the degree of activation of the peripheral blood and/or tissue eosinophils found in conditions characterized by elevated levels of eosinophils [ Time Frame: Ongoing ]
- To investigate the functional role of eosinophils in immunologic and inflammatory reactions [ Time Frame: Ongoing ]
- To determine mechanisms inducing peripheral blood and tissue eosinophil responses by evaluating these cells and other immune reactants in patients with a variety of eosinophilic conditions [ Time Frame: Ongoing ]
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00001406
|Contact: Nicole C Holland-Thomas, R.N.||(301) firstname.lastname@example.org|
|Contact: Amy D Klion, M.D.||(301) email@example.com|
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike||Recruiting|
|Bethesda, Maryland, United States, 20892|
|Contact: For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR) 800-411-1222 ext TTY8664111010 firstname.lastname@example.org|
|Principal Investigator:||Amy D Klion, M.D.||National Institute of Allergy and Infectious Diseases (NIAID)|