A stem cell donor from London has said it was "emotional" to meet the woman whose life he helped to save.
Callum Kennedy-Mann flew to Pennsylvania in the US to meet Diane Fargo at the end of 2022.
His stem cell donation helped to treat the aggressive form of leukaemia she had been suffering with.
Ms Fargo described the 22-year-old lifeguard from Stoke Newington as her "guardian angel".
Stem cell drive to boost diversity among donors
Mr Kennedy-Mann was surprised to receive a call that he was a genetic match with Ms Fargo while he was studying at York University in 2019.
He had forgotten that he had signed up to the stem cell register put together by Anthony Nolan - a charity helping those with blood cancer - when he was 16.
"I didn't hesitate in saying I'd do it after they told me I was the best possible match," Mr Kennedy-Mann said.
"It was instinctive for me, knowing I could have a huge impact on someone's life."
'Most emotional moment'
Two years after the donation he heard that Ms Fargo was recovering well from the treatment.
"That was the most emotional moment for me - receiving a letter telling me she was alive," Mr Kennedy-Mann said.
The pair met when Ms Fargo offered Mr Kennedy-Mann and his girlfriend the chance to travel to the US and they spent Thanksgiving together.
Mr Kennedy said meeting Ms Fargo was "so natural".
"I felt like I already knew her, and we didn't feel like strangers at all," he said.
Ms Fargo said: "Callum is my guardian angel and to have the opportunity to host him and his girlfriend over Thanksgiving holiday was a true blessing."
She added: "I am so thankful for Anthony Nolan and will be forever grateful to Callum for his kind and selfless sacrifice."
Anthony Nolan Chief executive Henny Braund said that men under 30 were 13 times more likely to be selected for donation in the UK, and called for more young men to sign up.
The charity also urged those from a minority ethnic background to register.
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