Effects of immunosuppressants on induction of regulatory cells after intratracheal delivery of alloantigen.
BACKGROUND
We previously reported that intratracheal delivery (ITD) of alloantigen generated regulatory cells in mice. Here, we examined the effect of various doses of conventional immunosuppressants (FK506, cyclosporine A, azathioprine, mycophenolate mofetil, and rapamycin) on inducing regulatory cells in our model.


METHODS
CBA mice (primary recipients) were given C57BL/6 splenocytes by ITD and either no additional treatment or various doses of an immunosuppressant. Seven days later, splenocytes from these mice were adoptively transferred into naive secondary CBA recipients that underwent C57BL/6 cardiac grafting the same day.


RESULTS
Adoptive transfer from primary recipients given ITD of splenocytes alone induced prolonged allograft survival in secondary recipients (median survival time [MST], 50 days), suggesting that regulatory cells were generated. When ITD of alloantigen was combined with daily administration of 0.1 mg/kg FK506 or 0.2 mg/kg rapamycin, graft survival was similarly prolonged (MST 55 and 50 days, respectively). When combined with 20 or 40 mg/kg MMF or 0.4 mg/kg rapamycin, the majority of recipients demonstrated indefinite survival (MST, >100 days in all groups). When ITD of alloantigen was combined with 0.3, 0.5, or 1.0 mg/kg FK506; 5, 10, or 25 mg/kg cyclosporine A; or 1.0 or 2.0 mg/kg azathioprine, allografts were rejected acutely (MST 7-13 days).


CONCLUSIONS
Generation of regulatory cells by ITD of alloantigen was facilitated by mycophenolate mofetil and high doses of rapamycin but abrogated by cyclosporine A, azathioprine, and high doses of FK506. Low doses of rapamycin and of FK506 did not interfere with generation of regulatory cells.
Shibutani
Shintaro
S
Department of Surgery, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
Inoue
Fumihiko
F
Aramaki
Osamu
O
Akiyama
Yoshinobu
Y
Matsumoto
Kenji
K
Shimazu
Motohide
M
Kitajima
Masaki
M
Ikeda
Yoshifumi
Y
Shirasugi
Nozomu
N
Niimi
Masanori
M
D019264:Adoptive Transfer; D000818:Animals; D001379:Azathioprine / Q000494:pharmacology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D016572:Cyclosporine / Q000494:pharmacology; D003713:Dendritic Cells / Q000276:immunology; D006085:Graft Survival / Q000276:immunology; D007165:Immunosuppression Therapy; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000378:metabolism; D007519:Isoantigens / Q000008:administration & dosage* / Q000276:immunology*; D051379:Mice; D009173:Mycophenolic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D020123:Sirolimus / Q000494:pharmacology; D013154:Spleen / Q000166:cytology / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D016559:Tacrolimus / Q000494:pharmacology; D013997:Time Factors; D014019:Tissue Donors; D014132:Trachea / Q000276:immunology*; D014180:Transplantation
D007166:Immunosuppressive Agents; D007376:Interleukin-2; D007519:Isoantigens; D016572:Cyclosporine; D009173:Mycophenolic Acid; D001379:Azathioprine; D020123:Sirolimus; D016559:Tacrolimus