LEAPS vaccine technology generates dendritic cells to stimulate immune system to fight viral illnesses

CEL-SCI Corporation (NYSE AMEX:CVM) and researchers at the Northeastern Ohio Universities Colleges of Medicine and Pharmacy (NEOUCOM) jointly announced today that a LEAPS^TM-based vaccine (Ligand Epitope Antigen Presentation System) study has demonstrated the technology's potential using dendritic cells to stimulate the immune system to fight viral illnesses and other diseases. Results of the study were selected for an oral presentation at the prestigious Federation of Clinical Immunology Societies (FOCIS) Annual Meeting in Boston, Mass., June 27, 2010, and are to be published in Vaccine, a peer-reviewed, pre-eminent journal for vaccines and vaccination. Patricia Taylor, a Ph.D. candidate at NEOUCOM and Kent State University, was one of a select few scientists at the meeting to be awarded a prestigious travel scholarship for the presentation. She is working with Dr. Ken S. Rosenthal, Professor of Microbiology and Immunology at NEOUCOM, and Dr. Daniel Zimmerman, CEL-SCI's Senior Vice President of Research, Cellular Immunology.

“This may lead to new treatments against many diseases.”

The study showed that it is possible to convert normal mouse bone marrow cells into dendritic cells that can be transferred into other mice to confer 100 percent protection from a 3-4 fold LD₅₀ dose viral (HSV-1) challenge. The LEAPS vaccine (JgD) contains a peptide from a herpes simplex virus type 1 protein. Dendritic cells activate an immune response which provides protection against HSV disease and death. Most of the mice receiving the JgD treated dendritic cells showed no disease and all survived. In contrast, almost all of the mice receiving no immunization or dendritic cells treated with an HIV vaccine (JH) or other control treatments showed serious disease and died.

Previously, this team had demonstrated that immunization of mice with a LEAPS vaccine alters the balance of cytokines (immunological hormones) to favor the development of Th1 cell-mediated responses. Th1 cellular immune responses are needed for protection against many viral diseases and have anti-tumor activity. Other studies demonstrated that a different J-LEAPS vaccine can also modulate an autoimmune condition to block the progression of rheumatoid arthritis in a mouse model of the disease. In a parallel study, Dr. Taylor has also shown that JgD promotes the maturation of human monocytes into Th1 response promoting dendritic cells.

"These findings give us a new way to prepare personalized vaccines that stimulate the immune system to fight viral and other diseases with LEAPS conjugates," said Dr Zimmerman. "This may lead to new treatments against many diseases." Dr. Rosenthal will introduce the LEAPS dendritic cell vaccine approach as a potentially new personalized immunotherapy for chronic viral infections and tumors at the Cancer Vaccine Meeting in Cambridge, Mass., June 30, 2010.

The LEAPS vaccines in this study consist of a portion of an HSV or HIV protein attached to a portion of another very small protein immune cell binding ligand (ICBL) chosen to promote and direct the immune response. By themselves, neither the ICBL nor the viral peptides initiate protection, but when conjugated together, the LEAPS vaccines promote immune responses that can protect against HSV-1.

Vaccination against HSV and HIV has the potential to prevent initial infection, prevent or lessen the severity of disease and prevent spread of the virus to sexual partners, as well as to neonates and newborns. LEAPS-peptide vaccines and LEAPS-based dendritic cell vaccines have the potential to provide safe and effective protection and treatment for infectious, oncogenic and autoimmune diseases.