Effect of IL-2-Bax, a novel interleukin-2-receptor-targeted chimeric protein, on bleomycin lung injury

Michael J. Segel*, Kami Aqeilan, Keren Zilka, Haya Lorberboum-Galski, Shulamit B. Wallach-Dayan, Michael W. Conner, Thomas G. Christensen, Raphael Breuer

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

16 Scopus citations


The role of lymphocytes in the pathogenesis of lung fibrosis is not clear, but the weight of the evidence supports a pro-fibrotic effect for lymphocytes. The high-affinity interleukin-2 receptor (haIL-2R) is expressed on activated, but not quiescent, T lymphocytes. This selective expression of haIL-2R provides the basis for therapeutic strategies that target IL-2R-expressing cells. We hypothesized that elimination of activated lymphocytes by IL-2R-targeted chimeric proteins might ameliorate lung fibrosis. We investigated the effects of IL-2-Bax, a novel apoptosis-inducing IL-2R-targeted chimeric protein, on bleomycin-induced lung injury in mice. Treatment groups included (i) a single intratracheal instillation of bleomycin and twice-daily intraperitoneal injections of IL-2-Bax; (ii) intratracheal bleomycin and intraperitoneal IL-2-PE664Glu, an older-generation chimeric protein; (iii) intratracheal bleomycin/intraperitoneal PBS; (iv) intratracheal saline/intraperitoneal PBS. Lung injury was evaluated 14 days after intratracheal instillation by cell count in bronchoalveolar lavage (BAL) fluid, semi-quantitative and quantitative histomorphological measurements and by biochemical analysis of lung hydroxyproline. Bleomycin induced a BAL lymphocytosis that was significantly attenuated by IL-2-Bax and IL-2-PE66 4Glu. However, morphometric parameters and lung hydroxyproline were unaffected by the chimeric proteins. These results show that IL-2-Bax reduces the lymphocytic infiltration of the lungs in response to bleomycin, but this effect is not accompanied by a decrease in lung fibrosis.

Original languageAmerican English
Pages (from-to)279-288
Number of pages10
JournalInternational Journal of Experimental Pathology
Issue number5
StatePublished - Oct 2005


  • Apoptosis
  • Fibrosis
  • Genetic engineering
  • Immunotherapy
  • Interstitial lung disease


Dive into the research topics of 'Effect of IL-2-Bax, a novel interleukin-2-receptor-targeted chimeric protein, on bleomycin lung injury'. Together they form a unique fingerprint.

Cite this