Lymphoid tissue responses to emulsified perfluorochemicals: comparative aspects.

The effects of a single, low dose (10 ml/kg) injection of the perfluorochemical (PFC) emulsion, Fluosol-DA 20%, on lymphoid tissues and antibody production against sheep red blood cells (SRBC) have been studied relative to the timing of immunization in rats and mice. Intravenous (i.v.) or intraperitoneal (i.p.) injection of emulsion in both species produced alterations in lymphoid tissue weights and the magnitude of these responses was highly tissue- and species-specific. Injection of Fluosol-DA tended to potentiate the humoral immune response to SRBC but this depended on timing and route of emulsion administration relative to immunization. We conclude that lymphoid tissue responses to emulsified PFCs are highly variable and depend upon a number of factors including: emulsion composition and dose; route and timing of administration relative to immunological "challenge"; tissue and species examined.