The virus, the human T lymphotropic virus type 1 (HTLV-1), is transmitted mainly when infected cells known as T lymphocytes, or T cells, touch uninfected T cells.
The finding helps explain how this cell-to-cell transmission happens. It suggests that an HTLV-1 protein known as p12 activates infected T cells and causes them to become sticky and adhere to other T cells.
The greater stickiness happens because the p12 viral protein causes special adherence proteins found on the surface of T cells to cluster in large groups ?something that normally happens when T cells touch to communicate with one another during an immune response.
The findings also suggest that a drug that inhibits the p12 protein might also help prevent HTLV-1 transmission.
The research, published in the May issue of the Journal of Immunology, was led by scientists with The Ohio State University Comprehensive Cancer Center and the OSU College of Veterinary Medicine.
"This study indicates that the p12 protein plays an important role in programming infected cells for cell-to-cell transmission," says principal investigator Michael D. Lairmore, professor and chair of veterinary biosciences and a member of the OSU Comprehensive Cancer Center.
"It shows that this virus takes advantage of something that T cells do normally, but, in this case, the virus is stimulating the interaction with other T cells rather than a normal immune response."
HTLV-1 infects an estimated 15 to 25 million people worldwide. About 5 percent of those infected develop adult T cell leukemia or lymphoma (ATLL), an aggressive disease characterized by a long latent period and the proliferation of T cells. The infected cells are spread from person to person during sexual activity and by blood and breast milk.
Source:Ohio State University