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Large patient base places MUSC at forefront of sickle cell research by Heather Woolwine Public Relations With the arrival of National Sickle Cell Awareness Month, MUSC remains perched at the forefront of sickle cell research.   “MUSC is in a great position to participate in sickle cell research because of our large patient base and our willingness to collaborate with centers and hospitals across the country,” said Sherron Jackson, M.D., director of MUSC’s Pediatric Sickle Cell Clinic.   The only one of its kind in the Lowcountry, Jackson’s sickle cell clinic not only promotes awareness of the disease, but also participates in research geared towards better treatments and therapies for those suffering from it.   Two very different therapies hold promise in treatment of sickle cell patients, the first a curative approach known as bone marrow transplantation.   Already a cancer treatment, bone marrow transplants remain a tricky process. Only for patients with severe manifestations like acute chest syndrome or stroke, the number of transplants performed in sickle cell patients is still relatively small due to a limited number of compatible bone marrow donors.   Donors’ proteins within the bone marrow must match completely with the sickle cell patient’s proteins for the transplant to be successful. “The major problem with this method continues to be finding suitable donors,” Jackson said. “Only about 25 percent of the time are we able to find a suitable donor, with the best option being a full sibling who does not have sickle cell disease.”   In recent years, saving the cord blood from the birth of a child has become an option for sickle cell patients eligible for transplant. “In terms of cord blood, fewer proteins have to match,” Jackson said. “Fortunately, it’s becoming more practical and economical for parents to store cord blood, as opposed to 15 years ago.”   A second ther-apy called hydroxyurea is chemotherapy that turns on a patient’s fetal hemoglobin gene, normally turned off after the first year of life. Patients receiving this therapy make more fetal hemoglobin than sickle hemoglobin and are thus able to combat sickling symptoms more effectively.   Although more commonly used in adults, researchers are now looking at the effects of hydroxyurea in pediatric patients, including an MUSC study with sickle cell infants and toddlers.   A general concern among sickle cell practitioners is that because children are naturally at higher risk for infection, hydroxyuera might increase the possibility for fatal bacterial infection as it can weaken the body’s immune system. However, several studies have shown that safe dosages of hydroxyurea do exist for pediatric sickle cell patients. MUSC and Jackson are part of national trial moving into its second and final year of study that is exploring those dosages safe for children. Called the Baby HUG study, some patients are receiving the medication while others are receiving a placebo. Neither the patients nor the physicians will know who received what until the study is completed to protect its validity.   “One of the things to consider when involving pediatric patients in hydroxyurea treatment is that the medication may suppress the white blood cell count,” Jackson said. “We monitor them very closely and if a patient develops a fever, then we perform blood work and treat the patient with antibiotics.”   At the conclusion of the study, Jackson and her colleagues hope to see fetal hemoglobin percentages increase from 2 or 3 percent to approximately 30 percent. By increasing a patient’s fetal hemoglobin almost tenfold, the difference in quality of life for that patient would be significant.   Although more convenient and economical, not every patient responds to hydroxyuera and candidates must belong to the same high-risk group eligible for transplants. It’s also important to note that it is not a pain management therapy.   “I remind patients that hydroxyuera is a long-term treatment and must be taken for the duration of their lives. It takes around four months to begin to see the effects of the medication,” Jackson said.   According to Jackson, hydroxyuera may also be able to help patients who suffer a stroke who must then undergo chronic blood transfusion therapy. Jackson and her colleagues will participate in a National Institutes of Health multi-center trial using hydroxyuera to manage these patients.   While the transfusions these patients receive are life saving, as transfusions increase, so do complications for patients, including rejection of transfused blood cells. The pilot studies using hydroxyuera for stroke patients are promising and with funding granted in July, things should be underway in the next six months. “It’s really an exciting option,” Jackson said. “Perhaps through this study we’ll be able to determine that some stroke patients won’t need chronic transfusions through adulthood.”   To explore another treatment approach, Jackson and her colleagues are participating in a study dubbed ASSERT. The clinical trial is sponsored through a pharmaceutical company who believes its product, Icagen, could help sickle cell patients. The drug acts to prevent the dehydration in the red blood cell that leads to the characteristic sickling of hemoglobin in patients with the disease. “If the drug prevents the sickle hemoglobin from polymerizing, then there would be fewer sickling complications and fewer pain episodes.”   By involving patients, ages 16 and older, the study allows pediatric and adult sickle cell experts the opportunity to expand the study size for more credible results, and hopefully a new treatment that would benefit all ages of sickle cell patients.   For more information about Jackson’s various research studies or to contact the    MUSC Pediatric Sickle Cell Clinic, call 792-1414.        Friday, Sept. 2, 2005 Catalyst Online is published weekly, updated as needed and improved from time to time by the MUSC Office of Public Relations for the faculty, employees and students of the Medical University of South Carolina. Catalyst Online editor, Kim Draughn, can be reached at 792-4107 or by email, catalyst@musc.edu. Editorial copy can be submitted to Catalyst Online and to The Catalyst in print by fax, 792-6723, or by email to petersnd@musc.edu or catalyst@musc.edu. To place an ad in The Catalyst hardcopy, call Community Press at 849-1778.