In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: Fusidic acid is an antibiotic with T - cell specific immunosuppressive effects similar to those of cyclosporin .
### Output Text:
Fusidic acid is an antibiotic with T - cell specific immunosuppressive effects similar to those of <span class="chemical">cyclosporin</span> . 