Impact of Host Iron Status and Iron Supplement Use on Erythrocytic Stage of Plasmodium Falciparum

Purpose: This proposal is aimed at studying the effect of an individual's iron status and
iron supplementation on the growth and viability of the malarial parasite Plasmodium
falciparum. The overall goal is to provide evidence to support the development of
evidence-based programs to improve global health policy on iron supplementation in areas of
the world with high malaria transmission. Current WHO recommendations include routine
supplementation of women and children. Recently however, the wisdom of this policy when
applied to areas afflicted with high rates of malaria has come under scrutiny. This proposal
will study the effects of red blood cells (RBCs) and sera from iron overloaded patients
(with hereditary hemochromatosis), iron deficient patients, and iron replete individuals
taking oral iron supplements. This proposal will attempt to identify the mechanism by which
the human host's iron status and iron supplement use affects the growth and viability of the
P. falciparum parasite in red blood cells.

Participants: Healthy adult volunteers, adults with iron deficiency anemia, and patients
with hereditary hemochromatosis will be enrolled in this study. Fifteen individuals will be
recruited under each of the above three settings. This study involves only subjects over 18
years of age and both males and females will be included.

Procedures (methods): Participation in the study involves undergoing a series of screening
tests and donation of blood and either a single time point (for hemochromatosis patients) or
a total of three pre-specified time points (for healthy volunteers and those with iron
deficiency). The healthy individuals will be asked to take oral iron supplements once daily
(325 mg ferrous sulfate) for the duration of this study. Patient's blood will be separated
by centrifugation into RBCs and sera, both of which will be used for in vitro studies on the
impact of iron status on the growth and viability of Plasmodium falciparum.

Inclusion Criteria:

All study participants will need to meet the following eligibility criteria for
participation in the study:

1. 18 years of age or older

2. Agree to HIV testing

3. No known malignancy

4. Agree to pregnancy testing (when applicable)

5. Do not have sickle cell disease or trait

6. Do not have thalassemia or thalassemia trait

7. Not taking iron supplementation

8. Have O+ or A+ blood group, and

9. Consent to participate in the study

In addition to the above common study screening tests, additional specific eligibility
criteria for the three study groups are as follows:

1. Individuals with iron deficiency:

Iron deficiency will be diagnosed using the biochemical parameters listed below

- Serum iron: <40 µg/dL

- Iron binding capacity (transferrin): <40 µg/dL

- Saturation (SI/TIBC): <10 percent

- Hemoglobin: < 9 g/dL

- Red cell morphology: Hypochromia and microcytosis

- Plasma or serum ferritin: <10 ng/mL

2. Individuals with Hereditary Hemochromatosis (HH):

In addition to confirmation with genetic testing, it is expected that patients with
HH will have the biochemical parameters listed below. From the genotype standpoint,
only patients homozygous for the C282Y and H63D mutations and those that are compound
heterozygotes for C282Y/H63D will be enrolled. These are the mutations most
associated with iron overload in HH patients. Note that we will have different
criteria for men and women. Since women (with and without hemochromatosis) have
greater iron losses (secondary to menstruation) in comparison to men, they usually
have lower iron stores, lower ferritin levels and lower iron saturation.

Biochemical parameters:

- Biochemical markers for patients with HH

- Serum iron: >65 µg/dL

- Saturation (SI/TIBC): > 60% men; >50% women

- Plasma or serum ferritin: >300ng/mL men; >200 ng/mL women

Each study participant will have been diagnosed (via genetic testing) with HH prior
to the enrollment.

3. Healthy volunteers:

Exclusion Criteria:

Patients with HIV, that are pregnant, and those with Sickle cell anemia/trait or
Thalassemia/Thal trait will not be eligible to participate in this study as these
conditions could interfere with the outcomes of the in vitro studies performed in this
proposal.