The Role of MIP-1α in Experimental Hypersensitivity Pneumonitis

S. rectivirgula (SR) causes Farmer’s Lung Disease, a classic example of hypersensitivity pneumonitis (HP). We utilized a model of experimental hypersensitivity pneumonitis (EHP), antibody to MIP-1α and MIP-1α−/− mice, to test the hypothesis that MIP-1α is essential in the development of EHP. Treatment of C57BI/6 mice with anti-MIP-1α antibody did not change the extent of pulmonary histology abnormalities, BALF cell number or characteristics, or BALF concentration of IL12p40, TNF, IL1α and IL6, after an i.t. challenge with SR. MIP-1α−/− animals responded similarly to wild-type (wt) animals in the extent and nature of pulmonary histologic changes and BALF cell number and type after a single i.t. injection of SR There was a dose-response relationship between the amount of SR and BALF IL12p40, MCP-1 and IL6 in both strains, and MIP-1α in wild-type animals. We next transferred SR cultured spleen cells from SR sensitized mice (both wt and MIP-1α−/−) to naïve recipients. Lung histology and BALF characteristics after SR i.t. challenge of the recipients were used to determine if adoptive transfer had occurred. Cultured cells from MIP-1α−/− animals were fully capable of transferring EHP to recipients. There was no difference of BALF TNF, IL6 and IL1α between the strains, but there was more MCP-1 and IL12p40 in the MIP-1α−/− mice than in the control mice. MIP-1α is not necessary for the recruitment of cells into the lung and BALF after i.t. administration of SR, or the development of cells able to adoptively transfer EHP.