ABSTRACT
Duffy gene (FY) codifies the transmembrane glycoprotein Duffy (gp-Fy) of 35 to 43 kDa which is moderately immunogenic. This glycoprotein is polymorphic, and constitutes the antigens of the Duffy histo-blood system which were designated receptors for chemokines and denominated DARC (Duffy antigen/receptor for chemokine). This receptor has an important role in the regulation of chemokine levels in the circulation, as it binds and adsorbs them on the surface of red cells as a reservoir. It plays a "sink" role, which can contribute to homeostasis by removing inflammatory chemokines from circulation as well as maintaining them in plasmatic levels. Chronic Chagas' cardiopathy (CCC) is the most frequent form of the disease. It is an inflammatory disease, in which infiltrated inflammatory cells play an important role in the development and progress of the infection. High chemokine levels in the plasma have been associated with the disease severity in patients with heart failure. In this context, the profile of DARC expression could play an important function as a receptor for chemokines in Chagas' disease, in patients with CCC, as it can modulate damage from this inflammatory disease.
Subject(s)
Chagas Cardiomyopathy , Chagas Disease , Chemokines , Duffy Blood-Group System , Receptors, Cell SurfaceABSTRACT
Malaria is an endemic parasitosis and its causitive agent, Plasmodium, has a metabolism linked to iron supply. HFE is a gene with the polymorphisms C282Y and H63D, which are associated with a progressive iron accumulation in the organism leading to a disease called hereditary hemochromatosis. The aim of the present study was to determine the allelic and genotypic frequencies of the HFE gene polymorphisms in malaria patients and blood donors from the Brazilian Amazon region. We screened 400 blood donors and 400 malaria patients for the HFE C282Y and H63D polymorphisms from four states of the Brazilian Amazon region by polymerase chain reaction and restriction fragment length polymorphism analysis. We did not find any C282Y homozygous individuals, and the only five heterozygous individuals detected were from Pará State. The most frequent genotype in the North region of Brazil was the H63D heterozygote, in both study groups. Our results contribute to the concept that the Brazilian Amazon region should not be regarded as a single entity in South America. These polymorphisms did not influence the symptoms of malaria in the population studied, as neither severe signs nor high parasitemia were observed. Therefore, different hereditary hemochromatosis diagnostic and control measures must be developed and applied within its diverse locations. Investigations are currently being carried out in our laboratory in order to determine the importance of the coexistence of hereditary hemochromatosis in patients affected by parasitic diseases, such as malaria.
Subject(s)
Humans , Animals , Female , Adult , Gene Frequency , Malaria/genetics , Polymorphism, Genetic , Alleles , Brazil/epidemiology , Case-Control Studies , Endemic Diseases , Heterozygote , Malaria/epidemiology , Malaria/parasitology , Malaria/blood , Prevalence , Plasmodium falciparum/parasitology , Plasmodium vivax/parasitologyABSTRACT
We describe a heterozygous case of Hb I-Philadelphia [alpha 16 (A14) LYS-->GLU] in a blood donor from the Acre State Blood Bank, in the Brazilian Amazon region. We confirmed the mutation by electrophoretic and chromatographic methods and by DNA sequencing. A literature search showed that this is the first description of this alpha globin mutant in a Brazilian Caucasian group. We also emphasize the importance of the hemoglobin study in blood donors for the purpose of the genetic counseling and quality assurance of the blood to be transfused. Screening tests for hemoglobin mutants are also important for gathering anthropological information about the Brazilian population.