TY - JOUR
T1 - Upregulation of p75 tumor necrosis factor alpha receptor in Mycobacterium avium-infected mice
T2 - Evidence for a functional role
AU - Corti, Angelo
AU - Fattorini, Lanfranco
AU - Thoresen, Ove Fredrik
AU - Ricci, Maria Luisa
AU - Gallizia, Anna
AU - Pelagi, Micaela
AU - Li, Yongjun
AU - Orefici, Graziella
PY - 1999/11
Y1 - 1999/11
N2 - The bacterial growth and the production of tumor necrosis factor alpha (TNF-α) and TNF receptors (TNF-Rs) in the spleen and blood of BALB/c mice challenged with Mycobacterium avium complex (MAC) were monitored. Infection developed in two phases: the first, up to day 21, was associated with rapid MAC multiplication in the spleen and a drop in the mycobacteremia, and the second was associated with control of the infection in both compartments. In the spleen, TNF-α and TNF-RII mRNA levels peaked on day 21 and then slowly decreased; however, no increase in the level of TNF-RI mRNA was observed throughout these experiments. The level of circulating soluble TNF-RII (sTNF- RII) was transiently increased after day 21. In a model in which overproduction of bioactive TNF-α was triggered in response to a second infection with MAC, an increased production of sTNF-RII by cultured splenocytes was also observed. Administration of an antagonist anti-TNF-RII monoclonal antibody (MAb 6G1) to infected mice inhibited the bacterial growth in the spleen, suggesting that the TNF-RII and/or sTNF-RH was functionally involved in the mechanisms that control the infection. Overall, these observations suggest that upregulation of TNF-RII or sTNF-RII contributes to modulation of the TNF-α antibacterial activity in MAC infections.
AB - The bacterial growth and the production of tumor necrosis factor alpha (TNF-α) and TNF receptors (TNF-Rs) in the spleen and blood of BALB/c mice challenged with Mycobacterium avium complex (MAC) were monitored. Infection developed in two phases: the first, up to day 21, was associated with rapid MAC multiplication in the spleen and a drop in the mycobacteremia, and the second was associated with control of the infection in both compartments. In the spleen, TNF-α and TNF-RII mRNA levels peaked on day 21 and then slowly decreased; however, no increase in the level of TNF-RI mRNA was observed throughout these experiments. The level of circulating soluble TNF-RII (sTNF- RII) was transiently increased after day 21. In a model in which overproduction of bioactive TNF-α was triggered in response to a second infection with MAC, an increased production of sTNF-RII by cultured splenocytes was also observed. Administration of an antagonist anti-TNF-RII monoclonal antibody (MAb 6G1) to infected mice inhibited the bacterial growth in the spleen, suggesting that the TNF-RII and/or sTNF-RH was functionally involved in the mechanisms that control the infection. Overall, these observations suggest that upregulation of TNF-RII or sTNF-RII contributes to modulation of the TNF-α antibacterial activity in MAC infections.
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M3 - Article
C2 - 10531226
AN - SCOPUS:0032733737
VL - 67
SP - 5762
EP - 5767
JO - Infection and Immunity
JF - Infection and Immunity
SN - 0019-9567
IS - 11
ER -