Expression of recombinase-activating genes (RAG-1 and 2) in human decidual mononuclear cells.
Recombinase-activating genes (RAG-1 and RAG-2) are expressed in immature T or B lymphocytes and possess activity to induce V(D)J rearrangement in TCR and Ig genes. We examined their expression in human decidual and non-pregnant endometrial samples using a highly sensitive RT-PCR technique. Expression of RAG-1 and 2 was noted in all (13/13) pregnant decidual tissues obtained at different gestational stages. After anti-human Ig treatment to rule out the possibility of RAG-1,2 expression from decidual B-cells, strong expression of RAGs was still noted in B cell depleted decidual cells in contrast to lymph nodes and PBMC that lost RAG mRNA expression after this treatment. After FACS mediated cell sorting, strong expression of RAG-1,2 was noted in CD16-CD56bright cells and weak expression in CD3+ cells. Although CD16-CD56bright cells lack surface CD3, they express CD3 epsilon mRNA only detectable by RT-PCR. Our results suggest the nature of decidual CD16-CD56bright cells as a progenitor of extrathymic T cells that possess RAG-1 and 2 mRNA as markers of their immaturity, and possibly differentiate into CD3+ extrathymic T-cells in the decidua under the influence of trophoblastic cells. We propose the human decidua as a new site of extrathymic T-cells differentiation and propose possible roles of trophoblastic cells to attract progenitor lymphocytes of bone marrow origin and trigger their TCR rearrangement as thymic epithelial cells.
Hayakawa
S
S
Department of Obstetrics and Gynaecology, Nihon University School of Medicine, Japan.
Saito
S
S
Nemoto
N
N
Chishima
F
F
Akiyama
K
K
Shiraishi
H
H
Hayakawa
J
J
Karasaki-Suzuki
M
M
Fujii
K T
KT
Ichijo
M
M
D000328:Adult; D001483:Base Sequence; D015139:Blotting, Southern; D017252:CD3 Complex / Q000096:biosynthesis; D004268:DNA-Binding Proteins; D003656:Decidua / Q000166:cytology* / Q000276:immunology*; D004717:Endometrium / Q000276:immunology; D005260:Female; D016654:Genes, RAG-1; D005865:Gestational Age; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008297:Male; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis
D017252:CD3 Complex; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011506:Proteins; C499311:RAG2 protein, human; D012333:RNA, Messenger; C064655:V(D)J recombination activating protein 2