A study entitled PF2: A NEW IMMUNOMODULATOR ACTING ON LYMPHOCYTE PROLIFERATION was presented at the 2004 National Congress of the Immunology Society by Dr. E. Jiménez-Medina, Dr. M. Martínez-Llamas, Dr. L. Paco, Dr. A. García-Lora, Dr. F. Garrido of the Hospital Universitario Virgen de las Nieves, Servicio de Análisis Clínicos, Granada. Garrido from the Hospital Universitario Virgen de las Nieves, Servicio de Análisis Clínicos, Granada. The aim of the study was to study the possible biological mechanism involved in the activity of PF2, focusing on the immunomodulatory potential on PBLs (peripheral blood lymphocytes) and NK cells.

PF2 is a polysaccharide obtained from Calendula Officinalis L.(Asteraceae), a component of Regis KH antiOx, by a new extraction process. In recent years, PF2 has been used in cancer patients, demonstrating that it has a double therapeutic effect:

• Strong antitumor effect
• Decrease in the side effects of chemotherapy.

One of the studies carried out consisted of analyzing the in vitro proliferation of human peripheral blood lymphocytes to determine whether the product has mitogenic activity. These lymphocytes were treated for 72 hours with different concentrations of PF2. In proliferation assays performed with PBLs showed an increase in lymphocyte proliferation 2 to 3 times higher than the control group and 10-20% with respect to Concanavalin A. In contrast, in NK cytotoxicity assays, no action was observed by PF2 on NK cells obtained from spleens of mice orally treated with this product.

The conclusions of this study show that PF2 has an effect on lymphocyte proliferation. It is a natural product, without toxicity, very common in most parts of the world and of low cost. In this way, this product is broad, being able to be applied to oncological patients, or with bacterial or viral infections.

Information on this study can be consulted on the web page of the Spanish Society of Immunology.