HLA-genome-edited iPS cells

HLA-genome-edited iPS cells

What are HLA-genome-edited iPS cells?

HLA-genome-edited iPS cells are designed to reduce the risk of immune rejection. The CiRA Foundation plans to manufacture and provide these cells by targeting HLA-A, -B, and -CIITA for the genome-edited knockout.


It has been estimated that only seven HLA-genome-edited iPS cell lines could cover 95% of the Japanese population, and 12 cell lines could cover the entire world. An even smaller number of cell lines could serve most of the world's population. In addition, compared to cells which have had their HLA completely knocked out to reduce the risk of immune rejection, our cells are capable of suppressing both T and NK cell activity, because they retain HLA-C and HLA-E.

The iPS cell line that using CRISPR-Cas9 genome editing to knocked out the CIITA gene that expresses HLA-A, HLA-B and HLA-Class II.

Future challenges

While the risk of immune rejection is reduced by HLA gene editing, it is not completely eliminated. Gene-edited technologies for clinical application have never been tested in Japan. Therefore, the safely and the quality of the cells must be examined carefully.


HLA, or human leukocyte antigens, describes cell-surface proteins that allow the body to distinguish self cells from non-self cells. HLA are found on various cell types other than leukocytes. There are tens of thousands of combinations of HLA types. HLA are classified into three types, but HLA-A, -B, and -C, which are all class 1, play a primary role in the immune response to transplanted cells.

HLA-genome-edited iPS cells list

Currently only research cells

Donor ID Gene Knockout Clone ID HLA information
DRXT × Ff-XT28s
HLA frequency ranking 3
Equivalent to DRXT 28s05
Ff-XT28s05-ABo_To Gene knockout
Cover 24% of the Japanese population.
QHJI Ff-I01s04-AB II-KO-16 Gene knockout
Cover 21% of the Japanese population.
Ff-I01s04-AB II-KO-50
Ff-I01s04-AB II-KO-54
Ff-I14s04-AB II-KO-7
Ff-I14s04-AB II-KO-13
Ff-I14s04-AB II-KO-24

※The above shares are offered at 50,000 yen
(excluding tax).
 Free of charge to non-profit institutions.