Active clinical trials for "T-Lymphocytopenia, Idiopathic CD4-Positive"

Human immunodeficiency virus (HIV) infection is characterized by persistent immune activation and a constant turnover of T cells. This leads to a precipitous fall in the number of T cells, as well as to an early immunosenescence. This results in increased susceptibility to opportunistic infections. In these patients, modulation of the immune response represents a promising mechanism to maintain immunological homeostasis and prevent the development of pathology. We hypothesize that the addition of pyridostigmine to the regular combined antiretroviral therapy will result in a decrease in T cell overactivation and a reduction in circulating inflammatory markers.

Background: Idiopathic CD4 lymphocytopenia (ICL) is a condition in which patients have low levels of T cells, a type of white blood cell that helps fight infection. Animal studies have shown that an experimental drug Interleukin 7 (IL-7), which is named CYT107, can increase the number and function of T cells. CYT107, however, has not been used in people with ICL. Objectives: To determine the safety of CYT107 in people with ICL. To determine whether CYT107 will increase the number and function of T cells in people with ICL. Eligibility: Patients 18 years of age and older diagnosed with ICL and who are at risk of becoming sick because of this condition are eligible for this study. In addition, patients must not be pregnant, or have other illnesses that would cause low CD4 T cell counts, such as human immunodeficiency virus (HIV) or human T-lymphotrophic virus (HTLV) infection. Design: The initial screening visit will include the following examinations and tests: A complete physical exam and medical history Blood analysis, including CD4 T cell count; complete blood count and additional blood tests to determine clotting ability and blood composition; thyroid, liver, kidney, and pancreatic function tests; HIV and HTLV tests; and tests for anti-IL-7 antibodies that block normal IL-7 activity Routine urine test Urine or blood pregnancy test for women Chest X-ray Electrocardiogram Spleen ultrasound. The baseline visit will include blood tests to determine levels of each of the major types of antibodies, a test of genetic background, and more detailed CD4 and protein analysis. In addition, leukapheresis (a procedure to collect large numbers of immune cells without red blood cells) will be done. Participants will also have the option of having colon and lymph node biopsies. The schedule will be as follows: Weeks 1, 2, and 3 (Cycle 1): Three weekly IL-7 dosing visits. Weeks 5, 8, and 12: Follow-up visits. Weeks 24, 25, and 26 (Cycle 2): Three more weekly IL-7 dosing visits. Weeks 28, 31, and 35: Follow-up visits. Week 48: End of study visit. Tests conducted before getting IL-7 will be repeated during the IL-7 cycles and follow-up visits to compare with earlier values. Optional colon and lymph node biopsies done at baseline will be repeated 1 6 weeks prior to Cycle 2 and 1 6 weeks prior to Week 48.

This study will evaluate HIV-negative patients with unusually low levels of CD4+ T lymphocytes (a type of white blood cell) to learn more about the clinical symptoms, cause, immunology, and biology of this problem. CD4+ T lymphocytes play an important role in immune function, and low counts may leave people susceptible to unusual infections. CD4+ T cell deficiencies are most often associated with HIV infection. Patients 8 years of age and older with CD4+ T cell counts below 300 cells/mm3 who test negative for HIV infection by standard blood tests may be eligible for this study. Patients' family members and partners may also be enrolled to investigate the possible role of a genetic factor or exposure to some agent in this problem. Patients will be evaluated at the NIH Clinical Center at least once, and generally two or more times. The evaluations, which may be done on an inpatient or outpatient basis, will include some or all of the following tests and procedures: Complete physical examination. Medical history, including questions about sexual contacts, intravenous drug use, travel, blood transfusions, previous illnesses, including sexually transmitted diseases, and health of family members. Urine test. Blood tests for routine and research purposes, including tests for HIV, hepatitis, syphilis and other infections, evaluation of immune function, and culture for viruses in the HIV family. No more than 1 pint of blood will be drawn every 6 weeks. Pregnancy test for women of childbearing potential. Skin tests for tuberculosis and immune function. These tests involve injecting a small amount of the substance to be tested just under the skin and looking for a raised area 1 to 2 days later. Apheresis. Whole blood is collected through an arm vein (similar to donating blood), and circulated through a cell separator machine, where it is spun to separate the components. The red cells are then returned to the patient either through the same needle or through a needle in the other arm, and the plasma and white cells are extracted for study. The procedure, which takes 1 to 2 hours, may be repeated up to 3 times. Family members will have 60 cc (4 tablespoons) of blood drawn to determine CD4+ T cell counts.

This retrospective observational study aims at the examination of regional differences in the procedure of referral for serological HIV testing between eastern (new) and western (old) German federal states.