Allogeneic Cell Engineering via Selective HLA-A/B Knockout

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Allogeneic transplantation is limited by immune rejection reactions such as host-versus-graft reaction (HVGR) and graft-versus-host reaction (GVHR), with existing methods like knocking out CD52 and HLA class I genes leading to increased production costs or susceptibility to host NK cell attacks, hindering widespread use.

Innovation Solution

An sgRNA combination targeting HLA class I genes, specifically HLA-A and HLA-B with high efficiency and HLA-C with low efficiency, is used to partially knock out HLA class I genes, reducing HVGR and enhancing the survival and anti-tumor effect of exogenous therapeutic cells.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If HLA class I genes are completely knocked out to reduce HVGR, then immune rejection is reduced, but exogenous therapeutic cells become susceptible to host NK cell attacks

Engineering Contradiction:
Improvehost-versus-graft reactionVSAvoidsusceptibility to NK cell attacks
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent applies local quality by differentiating the treatment of different HLA class I genes. Instead of uniformly knocking out all HLA class I genes, the invention specifically targets HLA-A and HLA-B for knockout while preserving HLA-C expression. This selective approach allows the therapeutic cells to resist HVGR (mediated primarily by HLA-A and HLA-B) while maintaining protection against NK cell attacks through retained HLA-C expression.

Inventive Principle:
Principle #3Local quality

2Reliability

If CD52 is knocked out to avoid alemtuzumab killing of therapeutic cells, then cell survival is improved, but production cost increases

Engineering Contradiction:
Improvecell survivalVSAvoidproduction cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent extracts the essential protective function from the CD52 knockout approach and implements it through a more economical method. Instead of knocking out CD52 (which requires expensive alemtuzumab treatment), the invention extracts and preserves the natural protective mechanism by retaining HLA-C expression, which inherently protects against NK cell-mediated lysis without requiring additional costly interventions.

Inventive Principle:
Principle #2Taking out (Extraction)

3Productivity

If allogeneic therapy is used to reduce production cost and waiting time, then manufacturing efficiency is improved, but immune rejection between subject and exogenous cells occurs

Engineering Contradiction:
Improveproduction efficiencyVSAvoidimmune rejection
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies parameter changes by modifying the HLA class I gene expression profile of the allogeneic therapeutic cells. By knocking out HLA-A and HLA-B genes while preserving HLA-C, the invention changes the immunological parameters of the cells to reduce antigenicity and minimize immune rejection responses, thereby enabling broader allogeneic compatibility without sacrificing the productivity advantages of allogeneic therapy.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The sgRNA combination effectively suppresses TCR engagement, reducing HVGR and increasing the survival time and therapeutic efficacy of allogeneic infused cells by retaining most HLA-C expression.

Implementation Method 1

As an emerging gene editing system, CRISPR-Cas has shown great application prospects in the fields of gene expression regulation, pathogenic gene screening and genetic disease treatment. CRISPR-Cas system mainly contains a Cas nuclease and a CRISPR locus

Methodology Applied
Scientific EffectCRISPR-Cas9 gene editing:

Implementation Method 2

CrRNA can guide the Cas protein to target nucleotide sequences through nucleic acid complementarity to achieve precise cutting

Methodology Applied
Scientific EffectNucleic acid complementarity:

Implementation Method 3

retaining most of the HLA-C expression can reduce the killing of allogeneic infused exogenous therapeutic cells by host NK cells

Methodology Applied
Scientific EffectNK cell recognition and killing mechanism:

Data Source

PatentEP4650447A1Composition and method for allogeneic transplantation
Publication Date: 2025.11.19 NANJING BIOHENG BIOTECH CO LTD
  • EP4650447A1 patent drawingFigure 1
  • EP4650447A1 patent drawingFigure 2
  • EP4650447A1 patent drawingFigure 3

AI summary

Provided are a composition and method for allogeneic transplantation. Provided is an sgRNA combination targeting HLA class I genes, which can knock out HLA-A and HLA-B with high efficiency, and knock out HLA-C with low efficiency. The sgRNA combination can be used for preparing engineered cells with modified HLA class I genes, and the obtained engineered cells can be further used in the prevention and/or treatment of diseases such as cancer, infection or autoimmune diseases.