ABSTRACT
Aldehyde dehydrogenase [ALDH] is a cytosolic enzyme that is responsible for the oxidation of intracellalar aldehydes. Elevated levels of ALDH have been demonstrated in murine and human progenitor cells compared with other hematopoietic cells, and this is thought to be important in chemoresistance and purification techniques and an indication of the proper function of the cell. A Flowcytometric method for the assessment of ALDH activity in viable cells recently has been developed. Forty six cord blood samples from mothers underwent normal delivery of full term infants were obtained, after informed consent. Mononuclear cells were obtained by Ficoll-Paque density centrifugation and ammonium chloride red cell lysis. Percentage of viable cells was determined by trypan blue exclusion dye. Cells were labeled with Aldefluor reagent [Stem cell technology, Vancouver., Canada] as described by the manufacturer. Cells were then stained with phycoerythrin [PE]-conjugated anti-CD34 [Miltenyi Biotec, Cologne, Germany] antibodies for 30 minutes at 4°C. Cells were washed and resuspended in phosphate-buffered saline [PBS] with 2% fetal calf serum. Cells were then analyzed on coulter epics flow cytometer. The mean percentage of ALDH enzyme expression among the, CD34[+] cells in the cord blood samples was 61.3% with a minimum of 6 and a maximum of 94.6%. Significant correlations were found between the wbcs count in the cord blood samples and both the CD34[+] cell count and the count of ALDH expressing cells, while, No correlation was found between the CD34[+] cells count or the ALDH expressing cells count in the cord blood samples and either the sex or the weight of the newborn. Identification and isolation of cells on the basis of ALDH activity provides a tool for their isolation and further analysis. In summary, a high ALDH-1 activity identifies CD34[+] cells in cord blood
Subject(s)
Humans , Male , Female , Fetal Blood , Antigens, CD34/blood , Aldehyde Dehydrogenase/bloodABSTRACT
Hepatocellular carcinoma [HCC] is considered as a long term multistage disease with multiple genetic alteration. Aldehyde dehydrogenase 2 [ALDH2] polymorphism may modify the risk of HCC. The aim of the present work was to evaluate the role of ALDH2 polymorphism as a predisposing factor for HCC in chronic hepatitis C virus [HCV] infected patients with cirrhosis for early detection. This study included fifty five subjects divided into three groups; twenty chronic hepatitis C patients with cirrhosis [group A], twenty chronic hepatitis C patients with cirrhosis and HCC [group B] and fifteen control subjects [group C]. The included patients were subjected to history taking, clinical examination, abdominal ultrasonography and liver biopsy [whenever possible]. All the subjects enrolled in this study were analysed for ALDH2 gene polymorphism. Genomic DNA prepared from leucocytes were used for polymerase chain reaction-restriction fragment length polymorphism [PCR-RFLP] technique. In addition, mitöchondrial ALDH activity was estimated in leucocytes. Of all fifty five subjects included in this study, six were heterozygous for ALDH2 gene mutation [ALDH2*1/*2] representing 10.9%, and the others were homozygous for the normal allele [ALDH2*11*1]. Non was detected to have homozygous mutant allele. The distribution among the patients groups was the same; three patients out of twenty in each group were heterozogous for the mutant gene [15%]. All the control subjects had normal homnozygous gene [ALDH2*1/*1]. The two patients' groups showed significantly higher percent of heterozygous mutant; ALDH2*1/*2 [X[2]=11.92,P=0.0027] and lower mitochondrial ALDH activity towards acetaldehyde [F=24.32, P=0.0002] in comparison to control group. However, non significant changes in both parameters were observed between the two patients' groups [P>0.05]. ALDH2 gene mutation could not be considered as a possible predictor for HCC in non alcoholic HCV-cirrhotic patients. However, these data did not exclude completely the relation to HCV infection and/or cirrhosis. Follow-up large scale studies are needed to investigate the exact link between ALDH2 mutation and cancer