S100-positive histiocytes in T-cell-dependent area in human lymph nodes express P-glycoprotein.
In the present study, we examined P-glycoprotein (P-gp)-expressing cells in human lymph nodes (LN) from patients with reactive lymph adenitis and various malignant lymphomas (ML). MDR1 mRNA was detected in all reactive LN and in 8 of 10 ML samples examined by reverse transcription polymerase chain reaction (RT-PCR). The signal intensity of the bands was stronger in samples from T-cell ML LN than in those from LN of reactive lymph adenitis and B-cell ML. Immunohistochemistry also showed positive reactivity with cellular components in the LN. The P-gp-positive cells, detected by UIC2, in reactive lymph adenitis and ML samples were large in size in the T-cell-dependent paracortical area in LN. Further, morphological characteristics were similar in UIC2-positive cells between reactive and ML LN. Double staining with UIC2 and a hematopoietic cell lineage-specific monoclonal antibody showed that UIC2-positive cell co-expressed S-100, but not other lymphocyte- and ML cell-specific antigens, indicating that these cells correspond to histiocytes in the T-cell-dependent paracortical area. Our results show that P-gp was expressed in histiocytes but not ML cells in LN, and suggest that this molecule may play an important role in the biological function of histiocytes and/or for maintenance of homeostatic levels in T-cell ML LN.
Second Department of Internal Medicine, Mie University School of Medicine, Tsu.
K
K
Nishii
K
K
Kita
H
H
Miwa
T
T
Ohno
M
M
Yamaguchi
K
K
Oka
S
S
Shirakawa
M
M
Fukumoto
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006644:Histiocytes / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000166:cytology / Q000378:metabolism*; D008199:Lymphadenitis / Q000378:metabolism* / Q000473:pathology; D008223:Lymphoma / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D009418:S100 Proteins / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D009418:S100 Proteins