The Effect of Echinacea purpurea on Stimulating IgM (Primary) and IgG (Secondary) Immune Responses in Male CD1 Mice

Echinacea purpurea, commonly referred to as the purple coneflower, is native to the United States and was first discovered by Native American Indians as a medicinal herb. Liquid extracts of Echinacea purpurea were evaluated for the capacity to stimulate total immunoglobulin immune responses in male CD1 (Charles River Laboratory) mice infected with an antigen of SRBC (sheep red blood cells). A control group (n=14) received the antigen but no Echinacea and a treatment group (n=15) received both the antigen and the Echinacea extract. Blood samples, obtained by cardiac puncture, were taken 48 hours after the second and final antigen injection. Blood samples were purified for IgG antibodies by the isolation of the IgG fraction (containing antibodies of all specifities) in a complex mixture by precipitation with saturated ammonium sulfate (SAS). In a 10% buffer of PBS, samples were then dialyzed for a 48 hour period at 4°C against three buffer changes (10% PBS). Once completing dialysis, samples were placed in the mass spectrophotometer for direct UV measurement of protein present in each sample. Protein concentration in samples revealed no significant difference between control and treatment groups. These results imply that Echinacea purpurea has no effect on the total number of antibodies, and IgG, or a B-cell mediated response, was never activated.