Overview
At KACTUS, we specialize in providing high-quality and reliable custom MHC complexes to meet your immune monitoring needs. With our extensive expertise in manufacturing MHC tetramers and monomers, we ensure that each product is tailored to your specific requirements. Before production, we'll discuss with you your specific project requirements including complex type, allele, peptide, tags, labels, etc. Then we'll conduct a feasibility assessment and provide a quote and estimated completion time. Throughout the process, we keep you informed and maintain confidentiality upon request. Fill out our custom MHC request form and our team will contact you soon to discuss your custom MHC complex request.
Available Alleles
Human
HLA-A*01:01
HLA-A*02:01
HLA-A*02:03
HLA-A*03:01
HLA-A*11:01
HLA-A*24:02
HLA-B*15:01
HLA-C*03:04
HLA-E*01:03
HLA-G
Mouse
H-2Kb
Qa-1b
Other Alleles
Our team can express other Class I or Class II alleles, or alleles from other species. Submit our custom MHC request form and we'll let you know the feasibility of your specific project.
Product Types
Monomers
Mammalian-expressed MHC-peptide complexes in natural conformation with biotinylation or fluorescent labeling
Tetramers
Four biotinylated MHC monomers bound to streptavidin for enhanced avidity to TCRs with biotinylation or fluorescent labeling
Peptide-ready MHC
Stabilized peptide-free MHC so you can load your own antigenic peptide in house
MHC-VLP
Multivalent MHCs containing approximtely 250 MHC copies per VLP with fluorescent labeling for enhanced detection of TCRs
Chimeric MHCs
MHCs with the human α3 immunoglobulin-like domain replaced with the mouse α3 domain to reduce non-specific antibodies during immunization
Request custom MHC:
Flexible features to meet your research needs
Mammalian or E. coli expression systems
Biological activity verification (ELISA, SPR, FACS, etc.)
Class I, Class II, or Other Species Alleles
Biotinylation or Fluorescent Labeling
Case Studies
Chimeric MHCs
After immunizing with standard MHC-peptide complexes (such as MHC class I), specific TCR-like antibodies are obtained, but at the same time, antibodies targeting non-antigenic epitopes of MHC α3 or β2M are also produced, increasing the time and difficulty of antibody screening. To combat this, we have creatively engineered species-chimeric MHC-peptide complexes, using a special design to replace MHC α3 or β2M with the corresponding domains from other species. This approach leaves more immunogenicity to the antigenic peptide, increasing the production of effective antibodies, thereby optimizing the screening process and reducing the screening intensity. Our chimeric MHCs are expressed in mammalian cells to maintain their natural conformation and demonstrate good bioactivity.
Figure 1. ELISA verification demonstrates that the Chimeric HLA-A02:01(mα3)&mB2M&NY-ESO-1 (SLLMWITQC) Monomer can bind to the HLA-A02:01&B2M&NY-ESO-1 (SLLMWITQC) Antibody. The activity is comparable to that of the non-chimeric HLA-A*02:01&B2M&NY-ESO-1 (SLLMWITQC) Monomer.
Figure 2. ELISA validation shows that the Chimeric HLA-A02:01(mα3)&mB2M&GP100 (YLEPGPVTA) Monomer can bind to the GP100 TCR&Anti-CD3 Bispecific Fusion. Its activity is comparable to the non-chimeric HLA-A02:01&B2M&GP100 (YLEPGPVTA) Monomer and superior to that of the chimeric monomer without special design.
Peptide-ready MHC
The discovery and identification of new antigens is an important process in immunotherapy. A key step in this process is detecting binding affinities of antigenic peptides with MHCs and the reactivity to TCRs. We have engineered functional Peptide-ready MHCs (prMHCs), which stabilized, peptide-free MHC monomers or tetramers. These prMHCs are available catalog and custom in Class I and Class II alleles.
Figure 3. Flow cytometry analysis of PE-labeled HLA-A02:01&B2M tetramers binding to Jurkat cells. TCR knockout Jurkat cells showed no significant binding to the tetramers, regardless of peptide presence. In contrast, 1G4 TCR monoclonal Jurkat cells exhibited high specific binding when the tetramers were complexed with the NY-ESO-1 (SLLMWITQC) peptide, while low binding was observed with an irrelevant peptide. This indicates that the loaded prMHC tetramer has high binding affinity with the TCR-expressing cells.
Webinar: Engineering MHCs as Versatile Reagents
Discover more about our MHC engineering by listening to our Chief Technology Officer, ManHee Suh, as he explains the innovative design of our diverse MHC molecules.
Custom MHC Workflow:
- Project Outline: After submitting your request, we'll set up an initial discussion to see what specifications you're looking and your applications.
- Product Development: We us structural information and our expertise in MHC engineering to produce mammalian-expressed single-chain trimer MHCs or peptide-ready MHCs.
- Quality Control: Your product will undergo purity and activity testing depending on the specifications outlined for your application. This may include HPLC, ELISA, or SPR testing services.
- Delivery: We'll deliver the final protein construct and any requested QC or other data in 6-8 weeks.
Request Custom MHC:
Peptide-Ready MHC
Load your own peptide in-house with our stabilized peptide-free MHC monomers & tetramers.
MHC-Peptide Complexes
Mammalian-expressed MHC Class I and II Monomers & Tetramers
CD3 Heterodimers
Bioactive CD3 homodimers and heterdimers with verified equal expression ratios
Soluble TCR Expression
Engineering and expression of soluble TCR including scFv-TCR, TCR-His, etc.
SPR Analysis Service
Surface plasmon resonance analysis of various sample combinations including MHC & TCR to assess binding affinities
Custom MHC Monomer or Tetramer