News Releases & Research Results Identification of key cells involved in an unknown infection route of human T-cell leukemia virus type 1 - Elucidation of the mechanism of infection through the placenta -

News Releases & Research Results


The results of research conducted by Senior Researcher Kenta Tezuka and Director Isao Hamaguchi of the Department of Safety Research on Blood and Biological Products, National Institute of Infectious Diseases and Visiting Researcher Naoki Fuchi and Professor Kiyonori Miura of the Department of Obstetrics and Gynecology, Nagasaki University School of Medicine.

The key results of research are as follows:

  • A highly sensitive viral detection method was established with tissues from human T-cell leukemia virus type 1 (HTLV-1)-infected individuals (carriers). Using this method, cells susceptible to HTLV-1 infection were identified in the placentas of pregnant carriers for the first time in the world.
  • Specifically, a larger number of infected cells remained active in the placentas of pregnant carriers with HTLV-1 detected in the cord (i.e., fetal) blood than those with no HTLV-1 detected in the cord blood, suggesting that HTLV-1-infected placental cells may function as a source of virus infection in the body.
  • The results of this research project should facilitate the development of new methods for preventing mother-to-child transmission of HTLV-1.

This program was conducted with the support of the Research Program on Emerging/Re-emerging Infectious Disease by AMED.

The results were published online in the American scientific journal, The Journal of Clinical Investigation, on October 20.


Tezuka K., et al. HTLV-1 targets human placental trophoblasts in seropositive pregnant women The Journal of Clinical Investigation
DOI: 10.1172/JCI135525


Last updated 10/20/20