The story of a cancer patient who survived with the help of blood donors is highlighted in the 5775 campaign of the Joely Bear Appeal, encouraging people to donate life-saving blood and stem cells.
In 2013, Joshua Lerner, 22, was diagnosed with Stage IV Hodgkin's Lymphoma, a blood cancer where the cells running through the veins have an abnormality.
He said: "The amazing work that the Joely Bear Appeal does to encourage people to consider donating blood is vital to ensure there is always a supply for those who need it."
Donors would be giving "something that your body makes for free that saves lives".
The charity was launched 20 years ago in memory of Joel Renak, son of co-founder Leigh Renak, who died from a rare liver cancer at the age of four. The new campaign is geared to adding 5,775 Jewish donors to the blood register during the current Jewish year.
You are giving something for free that saves lives
Chief Rabbi Ephraim Mirvis is among Orthodox, Reform and Liberal leaders who have contributed messages of support to the 5775 explanatory leaflet.