Cellular microchimerism as a lifelong physiologic status in parous women: an immunologic basis for its amplification in patients with systemic sclerosis.
OBJECTIVE
To quantitatively measure male DNA in blood from women with systemic sclerosis (SSc) and from controls and to evaluate in vitro the modulation of the microchimeric cell population size following immunologic stimuli that were expected to trigger antigen-specific T cells.


METHODS
A real-time polymerase chain reaction for a Y chromosome sequence was used to measure male DNA in blood from women with SSc and from controls who gave birth to sons. The in vitro change in the microchimeric cell population size was measured following immunologic stimuli, which were expected to trigger antigen-specific T cells.


RESULTS
Cellular microchimerism was found in SSc patients and controls, but the absolute amount of male DNA was higher in the patients, and the in vitro addition to blood mononuclear cells of an anti-CD28 costimulatory signal acted as a powerful amplification of microchimeric cells in 3 patients with SSc but not in controls.


CONCLUSIONS
Cellular microchimerism is a physiologic phenomenon in parous women. In SSc patients, cellular microchimerism is accounted for by a higher number of cells that have the characteristics of T lymphocytes specific to maternal allogeneic antigens.
Burastero
Samuele E
SE
IRRCS San Raffaele Scientific Institute, Milan, Italy.
Galbiati
Silvia
S
Vassallo
Antonia
A
Sabbadini
Maria Grazia
MG
Bellone
Matteo
M
Marchionni
Lucia
L
Smid
Maddalena
M
Ferrero
Elisabetta
E
Ferrari
Augusto
A
Ferrari
Maurizio
M
Cremonesi
Laura
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002678:Chimera; D041322:Chromosomes, Human, Y; D018920:Coculture Techniques; D004247:DNA / Q000097:blood / Q000235:genetics*; D005260:Female; D005331:Fetomaternal Transfusion; D006801:Humans; D008297:Male; D008875:Middle Aged; D010298:Parity; D011247:Pregnancy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012595:Scleroderma, Systemic / Q000235:genetics* / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
D004247:DNA