| City: |
|
Bethesda |
|
State:
|
|
MD |
| Zip Code: |
|
20892 |
| Conditions: |
|
Hemoglobin Mutations - Erythrocyte Variants |
| Purpose: |
|
This study will collect blood samples for use in laboratory studies of malaria. The World
Health Organization reports that 40 percent of the world's population is at risk for
malaria, mostly in the poorest countries. It is a serious disease caused by parasites. Each
year, 300-500 million infections lead to more than a million deaths. However, there are
traits in red blood cells (erythrocyte) that protect people against malaria. In this study,
polymorphism refers to the various kinds of red blood cell traits.
The sickle cell trait is an example of one that seems to offer a natural survival advantage
in children where malaria is common. Researchers at the Laboratory of Malaria and Vector
Research are investigating ways in which the blood cell traits can offer such protection,
and new knowledge gained can bring about medical advances. Of particular importance is
studying how the malaria organism, Plasmodium, survives inside different red blood cells. A
steady, consistent, and reliable supply of fresh whole blood is necessary for testing.
Patients 18 to 65, weighing more than 110 lbs. and who do not have anemia or known HIV,
Hepatitis C, or Hepatitis B may be eligible for this study.
Patients will undergo a medical history and general assessment including vital signs of
temperature, heart rate, and blood pressure. Blood will be collected from a vein in the arm,
or rarely a vein in the hand. A complete blood count, or CBC, will be done to ensure that
blood levels are sufficient and that blood donation is safe for a patient to do. Patients
need to have enough hemoglobin, the part of red blood cells that transports oxygen
throughout the body. The blood will also be tested to confirm the type of red blood cell
traits of patients. About 1 to 8 tablespoons may be collected, but most blood samples will
be small, that is, 1 to 4 teaspoons. After the patients' first visit, sessions will take
5-20 minutes. Blood collection will total no more than 2 cups from a donor during any 6-week
period. Although the frequency of blood donations is not known at this time, it is unlikely
that a patient will be asked to donate blood more than four times a year. It may be
important for patients to undergo a repeat CBC or tests for blood chemistry if results are
needed for research. Risks associated with blood collection are considered minimal. They
include discomfort, occasional bruising or bleeding at the puncture site, and faintness.
In this study, it is possible that a small amount of blood may be stored for future
research, to help the researchers to learn more about malaria. There are no plans for the
results from the various research laboratory tests to be made available to patients or to
their private doctors. However, patients in this study may discuss the results of routine
medical tests with the study investigators. Some of the blood collected will be tested for
genetic conditions. Through genetic testing, researchers can learn more about how health or
illness may be passed on to people by their parents, or from people to their children. All
results of tests will remain confidential. Blood samples will be labeled by code, and
reference to patients' identities will be protected.
Participants will receive $50 for each blood donation. This study will not have a direct
benefit for participants. Future research that uses their blood samples will help
researchers to learn about malaria as well as how to prevent or treat the disease.
|
| Study summary: |
|
This protocol is designed to provide a mechanism for investigators in the Laboratory of
Malaria and Vector Research (LMVR) to collect and process peripheral blood samples from
volunteer donors. Donors who meet standard eligibility criteria will be recruited to donate
blood via standard phlebotomy techniques at the NIH Clinical Center.
The LMVR has ongoing in vitro studies to characterize the effects of hemoglobin mutations
and erythrocyte polymorphisms on the pathogenesis of Plasmodium falciparum, the agent of the
most deadly malaria in humans. G6PD deficiency, hemoglobinopathies such as HbS, HbC, and
HbE, and the thalassemias are thought to have evolved as protective traits against malaria
in endemic areas of the world. However, the mechanisms by which these mutations exert their
protective influence are largely unknown. Culturing P. falciparum in erythrocytes carrying
protective traits will allow researchers in LMVR to characterize the cellular and molecular
bases of protection using in vitro methods such as growth analyses and electron microscopy.
To this effect, patients with known or suspected erythrocyte variants will be recruited in
addition to normal controls.
Signed informed consent will be obtained by an authorized investigator. The nature of the
study as well as the risks and benefits of the donation process will be explained to each
participant. Donors will be compensated for each blood donation or for unsuccessful
attempts at venipuncture. Samples will be used solely for in vitro research. To ensure
confidentiality, blood will be assigned a unique code; investigators listed on this protocol
will serve as the custodians of the codes that link the samples to the donors' identities. |
| Criteria: |
|
- INCLUSION CRITERIA:
Normal volunteer or volunteer with a known or suspected erythrocyte mutation.
Age greater than or equal to 18 and less than or equal to 65 years old.
Weight greater than 110 pounds.
Ability to sign the consent form.
Willingness to comply with study procedures.
EXCLUSION CRITERIA:
Transfusion of any blood products within the past 90 days.
Active bleeding.
Clinically apparent and/or symptomatic anemia (pallor, orthostasis, etc).
Self-reported history of HIV, Hepatitis B virus, or Hepatitis C virus infection.
Severe chronic disease (e.g. end-stage renal failure, malignancy, etc).
Significant medical history, physical examination, or laboratory test results indicating
that the subject should not participate in a clinical trial. |
|
|
|
|
|
|
|
|
If you are interested in this clinical trial please use the contact information above. If you would like to get additional information about this clinical trial please visit ClinicalTrials.gov.
|
| Trials Alerts: |
|
If you would like to be
notified of new clinical trials as they become available please
register for a free account.
|
|
| Data Source: |
|
ClinicalTrials.gov |
| Date Processed: |
|
July 21, 2010 |
Modifications to
this listing: |
|
Only selected fields are shown, please use the link
above to view all information about this clinical trial. |
|
|
|
|
|
|
|
|