Natural Killer Cells And Selected Enzyme! Metabolite Profiles In HIV Infection And Progression To Aids
Abstract
Acquired immune Deficiency syndrome (AIDS) is a disease of grave psychological and
economic concern. It effects all sectors of the community namely education, military,
education, health, transport and communication. To date, it is estimated that 40 million
people are infected with the virus globally of whom 28.5 million resides in Sub Saharan
Africa.
This study sought to evaluate the role of Natural killer cells in Human Immunodeficiency
Virus infection. It's correlation with CD4+, CD8+ cell numbers and CD4/CD8 ratio during
HIV infection and clinical progression to AIDS. Also the correlation of NK cells and liver,
kidney enzymes and metabolites was studied during HIV/AIDS progression. The study
further evaluated the possible causes of anemia that is usually observed in AIDS patients.
Blood samples were obtained twice at an interval of six months from 17 HIV infected
patients who were not on antiretroviral drugs and 3 HIV-negative patients (control). NK
cells were identified and quantified by tlowcytometry. Flowcytometric
immunophenotyping was used to identify and quantify the CD4+, CD8+ cells and the
CD4/CD8 ratio. Liver and kidney function enzymes and metabolites were measured
through absorbance photometry by diazo, enzymatic, calorimetric and kinetic methods.
Complete blood count parameters including red blood cell count, hemoglobin, hematocrit, mean.cell volume, red cell distribution width, mean corpuscular hemoglobin and mean corpuscular haemoglobin concentration as well as-albumin, ferritin and bilirubin were measured to determine the possible Cause of anemia that is observed in AIDS patients. 94% of HIV positive samples analyzed showed that HIV progression was associated with a decrease in NK. cell counts. There was a positive correlation between NK cells. CD4+ cell density and CD4/CD8 ratio. 90010 of HIV positive samples analyzed correlated negatively with CD8+ cells during HIVIAIDS progression. Also high NK. cell density was associated with elevated levels of liver marker enzymes i.e. above normal ranges (Appendix II).
Patients had low levels of red blood cells. hemoglobin. and hematocrit. mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. However serum levels of albumin. ferritin and bilirubin were normal. These parameters were normal in all HIV negative patients but the albumin and bilirubin serum levels were above the normal reference ranges. These results showed that anemia usually observed in HIV-positive patients may possibly result from poor absorption of iron from the gut rather than transport or storage defects. Thus a combination of natural killer cell number along with CD4+ cell density and CD4/CD8 ratio may be useful as markers for HIVIAIDS progression and may therefore be helpful in determining the timing of antiretroviral and antibiotic therapy as well as in dietary and general management of AIDS patients.
Citation
Master of Science in Biochemistry, University of Nairobi. 2007Publisher
University of Nairobi Department Of Biochemistry