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: In our experience and according to the literature , FK506 does not seem to cross - react with cyclosporin A ( CyA ) , an immuno - suppressive drug already known to induce MAHA .
### Output Text:
In our experience and according to the literature , <span class="chemical">FK506</span> does not seem to cross - react with <span class="chemical">cyclosporin A</span> ( <span class="chemical">CyA</span> ) , an immuno - suppressive drug already known to induce MAHA . 