Nuclear protein contents in peripheral blood mononuclear cells of trisomy 21 infants.
OBJECTIVE
The trisomy 21 (Ts21) or Down's syndrome (DS) phenotype is assumed to occur primarily by the expression/overexpression of some genes encoded by the extra chromosome 21. It has recently been shown by AgNOR staining that babies with Ts21 have more AgNOR area (more NOR proteins) and more RNA content in their peripheral blood mononuclear cells (PBMCs) than those of controls. The aim of this study was to test whether or not the nuclear proteins content of PBMCs from trisomy 21 babies/infants is higher than that of the controls.


METHODS
For this purpose, flow cytometric measurement of the stained PBMC nuclei was used. Nuclei from PBMCs was isolated and stained with propidium iodide and fluorescein isothiocyanate (PI/FITC) for DNA and protein estimation, respectively.


RESULTS
Mean nuclear protein content of Ts21's (N = 30, mean age = 3.46 +/- 3.05 years old) PBMCs was found statistically higher than that of the controls (N = 33, mean age = 3.79 +/- 1.93 years old) (P = 0.005, nonparametric Mann-Whitney U test for two independent variables). This means that the average nuclear protein content of PBMC from Ts21 infants is higher than that of the controls. Furthermore, there is a moderate negative correlation between the ages of the studied DS patients and the protein content in the nuclei of their PBMCs (Linear regression analysis: P = 0.002, r = -0.55). This correlation is not found with controls (P = 0.186, r = -0.24).


CONCLUSIONS
We have concluded that average protein content of PBMCs' nuclei from DS infants is higher than that of the controls, decreasing significantly with age.
The High School of Physical Education and Sports, Erciyes University, Kayseri, Turkey. zhamurcu@erciyes.edu.tr
Zuhal
Z
Hamurcu
Halil
H
Demirtas
Türkan
T
Patiroğlu
Sefer
S
Kumandas
D000367:Age Factors; D000375:Aging / Q000235:genetics / Q000378:metabolism; D034961:Antigens, Nuclear / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D002467:Cell Nucleus / Q000378:metabolism* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D004314:Down Syndrome / Q000097:blood* / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007963:Leukocytes, Mononuclear / Q000378:metabolism* / Q000473:pathology; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D011237:Predictive Value of Tests; D015854:Up-Regulation / Q000235:genetics
D034961:Antigens, Nuclear; D015415:Biomarkers; D009687:Nuclear Proteins; C051963:nucleolar organizer region associated proteins