Collection of Blood From Persons With Hemoglobin and Erythrocyte Polymorphisms for Laboratory Malaria Research
Condition: Hemoglobin Mutations; Erythrocyte Variants
MeSH terms: Malaria
Study type: Observational

Summary: 
      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.
    

Detailed description: 
      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.
    

Keywords: Sickle; Hemoglobinopathy; Thalassemia; G6PD; Plasmodium; Erythrocyte Variant; Hemoglobin Variant; Healthy Volunteer; HV