Publication Date:
1997-01-15
Description:
Interferon-γ (IFN-γ) is an immunoregulatory lymphokine that is primarily produced by T cells and natural killer cells. It has effects on T-cell, B-cell, and macrophage differentiation and maturation. We have developed transgenic mice that express elevated levels of IFN-γ mRNA and protein by inserting multiple copies of murine IFN-γ genomic DNA containing an Ig λ-chain enhancer in the first intron. The founder line carrying eight copies of this transgene has eightfold to 15-fold more IFN-γ–producing cells in the bone marrow and spleen than do nontransgenic littermates. Transgenic mice show a pronounced reduction in B-lineage cells in the bone marrow, spleen, and lymph nodes. In addition, single positive (CD4+,CD8− and CD4−,CD8+) thymocyte numbers are increased twofold, yet the number of splenic T cells is reduced by 50%. There is also a twofold to threefold decrease in the frequency and total number of myeloid progenitors in the bone marrow. Granulomatous lesions and residual degenerating cartilaginous masses are also present in the bones of these mice. Overall, our data show that the abnormal expression of IFN-γ in these transgenic mice results in multiple alterations in the immune system. These animals provide an important model to examine the role of IFN-γ expression on lymphoid and myeloid differentiation and function.
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine