TY - JOUR
T1 - Activation of unusual Mac-1+CD4-CD8- T cells bearing αβ antigen receptor in murine lungs during infection with Mycobacterium bovis BCG
T2 - Regulation by interferon-γ
AU - Teruya, Katsuji
AU - Kawakami, Kazuyoshi
AU - Saito, Atsushi
PY - 1996
Y1 - 1996
N2 - We have recently (Kawakami et al, Immunol. Lett. 1995;46: 143) demonstrated that unusual Mac1+CD4-CD8- T cells bearing αβ antigen receptor (Mac-1+ αβ T cells) reside in a considerable proportion in murine lungs. The present study was performed to examine the dynamics of accumulation of these cells in the lungs following intravenous administration of Mycobacterium bovis BCG (BCG). Mac-1+ αβ T cells accumulated rapidly 24 hr after infection, followed by a gradual increase over the observation period of 15 days. Furthermore, the expression of Ia, ICAM-1 and FcγR II/III on their surface intensified dramatically after BCG infection. The kinetics of enhancement of Ia expression was slower than that of ICAM-1, with the maximum level attained in one day in the latter molecule but in two weeks in the former. Neutralization of endogenous IFN-γ by specific mAb completely blocked the augmented expression of Ia on Mac-1+ αβ T cells after BCG infection, but did not have any significant effect on that of ICAM-1. In contrast, in vivo administration of IFN-γ enhanced the expression of ICAM-1 as well as that of Ia. Our results indicate that accumulation of Mac-1+ αβ T cells within the lung is associated with a differential change in the expression of surface antigens, and suggest that these cells may play a role in the host defense against mycobacterial infection.
AB - We have recently (Kawakami et al, Immunol. Lett. 1995;46: 143) demonstrated that unusual Mac1+CD4-CD8- T cells bearing αβ antigen receptor (Mac-1+ αβ T cells) reside in a considerable proportion in murine lungs. The present study was performed to examine the dynamics of accumulation of these cells in the lungs following intravenous administration of Mycobacterium bovis BCG (BCG). Mac-1+ αβ T cells accumulated rapidly 24 hr after infection, followed by a gradual increase over the observation period of 15 days. Furthermore, the expression of Ia, ICAM-1 and FcγR II/III on their surface intensified dramatically after BCG infection. The kinetics of enhancement of Ia expression was slower than that of ICAM-1, with the maximum level attained in one day in the latter molecule but in two weeks in the former. Neutralization of endogenous IFN-γ by specific mAb completely blocked the augmented expression of Ia on Mac-1+ αβ T cells after BCG infection, but did not have any significant effect on that of ICAM-1. In contrast, in vivo administration of IFN-γ enhanced the expression of ICAM-1 as well as that of Ia. Our results indicate that accumulation of Mac-1+ αβ T cells within the lung is associated with a differential change in the expression of surface antigens, and suggest that these cells may play a role in the host defense against mycobacterial infection.
KW - Double negative αβ T cells
KW - IFN-γ
KW - Lung
KW - Mycobacterium bovis BCG
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U2 - 10.1111/j.1348-0421.1996.tb03316.x
DO - 10.1111/j.1348-0421.1996.tb03316.x
M3 - Article
C2 - 8871528
AN - SCOPUS:0030032950
VL - 40
SP - 45
EP - 53
JO - Microbiology and Immunology
JF - Microbiology and Immunology
SN - 0385-5600
IS - 1
ER -