Timothy Ray Brown was an HIV-positive American who was cured by a unique type of bone marrow transplant.

Timothy Ray Brown was an HIV-positive American who was cured by a unique type of bone marrow transplant.

Reuters/Courtesy KPIX TV/Handout

A still image provided by KPIX TV and taken from the broadcaster's video footage shows Timothy Ray Brown during an interview at his home in San Francisco. Timothy Ray Brown, was a young HIV-positive American living and working in Berlin who had developed leukaemia and suffered a relapse after initial treatment.

A still image provided by KPIX TV and taken from the broadcaster's video footage shows Timothy Ray Brown during an interview at his home in San Francisco. Timothy Ray Brown, was a young HIV-positive American living and working in Berlin who had developed leukaemia and suffered a relapse after initial treatment. (Reuters/Courtesy KPIX TV/Handout)

A still image provided by KPIX TV and taken from the broadcaster's video footage shows Timothy Ray Brown during an interview at his home in San Francisco. Timothy Ray Brown, was a young HIV-positive American living and working in Berlin who had developed leukaemia and suffered a relapse after initial treatment.Reuters/Courtesy KPIX TV/Handout