Immunomodulatory role of bracken fern in laboratory rats: An experimental study

To investigate immunomodulatory role of bracken fern, rats were fed with 40% bracken fern powder (w/w) in concentrate ration for 12 months period. The animals were subsequently screened for the assessment of humoral immune response by indirect enzyme linked immunosorbant assay and cell-mediated immune response by delayed type hypersensitivity reaction against ovalbumin at 6 and 12 months post feeding interval. Decreased antibody level was observed in fern fed rats on 7^th day post challenge against ovalbumin during 6 months feeding interval. However, the antibody level remained unaltered on 14^th and 21^st day post challenge. Bracken fern enhanced cellular response against ovalbumin as evidenced by increase in ear pinna thickness in fern fed rats than control. Findings are further supported by histopathological observations.