TREG Therapy: Hope for the Holy Grail of Kidney Transplantation?

Figure 1. Map of the action links of various immunosuppressants: APC is an antigen-presented cell; IL is a lecithin; TCR is a T cellular conductor; JAK is Janus kinase; PI3K is phosphatidyl inositol-3-kinase; mTOR is a target protein of mammalian repamycin; CN is calcium-tuned phosphoric acid Enzymes; MAP kinases are silk-splitting active protein kinases; IKK is a nuclear factor-B kinase inhibitor; NFAT is activated T-cell nucleokines; AP-1 is an active protein factor; CKD/cyclins are periodic protein-dependent kinases; and IMPDH is a secondary jaundice nucleotide dehydrogenase.
nearly a decade, Treg cell therapy has conducted clinical trials on a range of transplant-related and non-transplant-related adaptations.
While these trials focus on safety, a core theme of all trials is the heterogeneity of GMP programmes in cell separation, operation, amplification, dosage, specificity, and post-drug cell tracking.
there is some consensus on standardization, the reality is that the novelty of Treg cells requires a lot of human research and focus on the optimization and standardization of GMP conditions.
part of the study that wants to make purer cells is based on the idea that the supply-specific TREG is better at treating transplant-effect T-cell responses than multiclonal TREG.
is important to clarify and use this mechanism in humans, as the purity of the product and the degree of allogeneic antigen specificity may have an impact on the therapeutic effect and the number of infusion cells.
a key advantage of the kidneys is that the living provider has a greater logistical support range, which provides continuous access to fresh feeder antigens, thus providing provider-specific Treg cells.
01, Treg classification Because the long-term side effects of chronic iso-transplant dysfunction and immunosuppression have not yet been fully resolved, transplant tolerance is still the holy grail in the field of organ transplantation.
this point, the increase of regulatory T-cells (Treg cells) in the micro-environment of extrinsic circulation and grafts is considered an important factor in inducing transplant tolerance.
human and mouse polyclonal Treg cells are classically divided into thymus Treg cells (tTreg), extrinsic Treg cells (pTreg) and induced Treg cells (iTreg), and some scholars distinguish between tTreg cells and pTreg cells by the high expression of Helios and Neuropilin-1 (NRP-1) on tTreg cells.
, however, Helios/NRP-1 itself cannot classify tTregs and pTreg cells in humans.
in the outer cycle, Tragh cells are characterized by CD4 plus, high levels of IL-2 subjects α chains (CD25high), low levels of CD127, and in-cell expression fork box P3 transcription factor (FOXP3 plus).
the adoption of new deep immune estypes confirms that the estype is more heterogeneity than originally thought, and that these data vary depending on the type, type, differentiation and micro-environment of Therg cells.
is shown in Figure 2 below.
further differentiation is made by identifying the coercion factor subject, as shown in Figure 3 below.
2. Distinguish CD4-T cells based on the expression levels of FOXP3 and CD45RA to determine the Treg cell subsethic. The diversity of Treg cells and their sub-groups.
(A) showed that Treg cells were divided into different groups based on the expression spectrum of their tendon receptors.
(B) shows a series of in-cell and/or extracellular markers identified on Treg cells, the special properties of Treg cells reported in current studies A: the possibility of plastic Treg cells using Th17-like effect cell esoplasty and function in inflammatory micro-environments is a key safety issue.
this is because Th17 cells are elevated in patients with acute and chronic iso-transplant rejection, which can lead to the deterioration of both conditions.
another way to interact with Treg-Th17 is that both originated initially from Naive CD4 plus cells, but their subsequent differentiation pathways were determined by the presence of IL-6-free conversion growth factor-β (for Treg) or IL-6 (for Th17) in the micro-environment, respectively.
potential of the micro-environment to convert Treg cells into Th17 cells that promote rejection may determine the point in time at which Treg cells are infused.
theory, Treg cell therapy can be proactive (i.e., before a patient's rejection) or reactive (i.e., given to a patient diagnosed with acute or chronic rejection).
, however, it is not clear whether Treg cells can induce tolerance in micro-environments that have been penetrated by Teffs.
B: Bystander suppression effect Treg cell therapy can be a potential problem, as Treg cells, once activated, can perform their inhibition function in a non-antigen-specific manner.
This effect, known as bystander suppression, was found in genetically modified mouse models, where antigen-specific CD4-CD25-T cells initially needed complementary table contact with TCR-mediated to activate.
, however, once activated, these cells can also inhibit the third-party antigen-specific effects of CD4-T cells.
effect was also shown in models in mice with allogeneic skin transplants.
If this phenomenon does recur in our patients, it may have an impact on regulating antigen-specific rejection while maintaining immunity to new tables of pathogens and potential tumors.
03, TREG representative test A. TRACT test s 14 trial recruited 9 people, cell separation using the Clinimacs system, 3 weeks amplification process using anti-CD3/CD28 antagonists, IL-2, TGF-β, Siromos.
results in purity of 98% CD4-CD25 plus and 80% FOXP3-plus, as well as similar levels of dDMylation.
patients received alemtuzumab treatment on the day of the transplant and on the 2nd day after surgery and maintained the use of MMF and his kemos (30th day to Siromos).
Thetreg cells are then infused on the 60th day.
in the two years reported, there were no cases of opportunity infection caused by cytocytovirus or polybromavirus, nor did there be a rejection response.
the trial did not report cases of opportgenic infection or rejection after patients receiving a new kidney transplant were infused with polyclonal Treg cells.
the B. TASK trial, which focused on the use of multiclosed Treg cells to regulate subclinical inflammation of transplanted kidneys.
this is an important research issue because subclinical inflammation is not diagnosed in a timely manner due to its chronic low-level nature and can lead to delayed allogeneic graft dysfunction.
patients with in-body enlargement of the in-body Treg cells, with an average dose of 320 x 106 cells.
2-week amplification: anti-CD3/CD28 antagonists, IL-2, heavy hydrogen glucose treatment.
the company will eventually get the purity of the products of 97% CD4 plus and 93% FOXP3 plus and 0.37% CD8 plus.
the trial recruited three patients who showed this inflammation in live tissue tests six months after the transplant (Banff i-and t-lt;2).
when patients get Treg cells, they are already taking MMF, thokmos and strong pine dragons.
importantly, from a safety perspective, the trial reported that Treg products did not directly cause SAE and no infection or graft dysfunction was reported during the one-year follow-up period.
, however, a key limitation of the current trial is that the radon signal cannot be detected for 3 months compared to what was not detected for more than 12 months in another trial.
this negates the long-term use of this technology.
were not reported in kidney biopsies 2 weeks and 6 months after infusion.
, it is unclear whether the products of dehydrogenated Treg cells can be migrated to transplants.
addition to this fact, two weeks after infusion, no patients showed an increase in EXPRESSION3 plus in the renal biopsy tissue, and only one patient experienced this at 6 months.
addition, although the technology helps with short-term tracking, it does not provide knowledge about the function of live Treg.
, in kidney transplantation, there was no SAE after infusion of FACS isolated and multiclonal amplified German Treg cells.
test is currently comparing the efficacy of multiclosed and isotrogen-specific Treg cells (NCT02711826).
C. The ONE trial (Germany) is an assessment of whether it is safe and feasible to reshape a patient's immune balance by infusion of autologous naturally regulated T-cells (nTreg) after kidney transplantation, and to gradually reduce lifetime high-dose immunosuppression (with limited efficacy, adverse reactions, high direct and indirect costs), while addressing several key challenges of Treg therapy in useful proof-of-concept disease models, such as simple and reliable manufacturing, the risk of over-immunosuppression, interaction with standard care drugs, and the stability of inflammation.
specific design is shown in Figure 4 below.
4. Clinical Trial Design Participants: Live Kidney Transplant recipients (ONEnTreg13, n=11) and corresponding reference group trials (ONErgt11-CHA, n=9).
interventions: CD4-CD25-FoxP3-nTreg products are injected intravenously with 0.5, 1.0, or 2.5-3.0×106 cell/kg body weight 7 days after kidney transplantation, followed by a gradual reduction of triple immunosuppression to a small dose of tekmos monotherapy until 48 weeks.
results measured: the main clinical and safe endpoints were evaluated by a comprehensive endpoint at week 60 and followed up for further three years.
assessment included the rate of acute rejection confirmed by biopsies, an assessment of injection nTreg-related adverse reactions, and signs of excessive immunosuppression.
end points include the function of allogeneic transplantation, the comprehensive combination of exploratory biomarkers, etc.
results are shown in Figures 5 and 6 and 7.
Figure 5. Main Endpoint Results Figure 6. In the case of monitoring patients' thokmos levels, the nTreg trial group (switched to monotherapy) gradually reduced immunosuppression compared to the reference group (continuous two- or triple-drug treatment) and 7. Isomorphic kidney transplantation Long-term follow-up Graph 8. Before and after infusion of serum or urine levels of inflammatory cytokines For all patients, the acquisition of 40-50 ml of outer blood in the two weeks before kidney transplantation produces nTreg products with sufficient yield, purity and functionality.
three nTreg dose increment groups were free of dose-limiting toxicity.
100% three-year survival rate of allogeneic grafts in the nTreg group and the reference group, with similar clinical and safety characteristics.
8 (73%) of the 11 patients treated with nTregs received stable single-drug immunosuppression, while the control group was still receiving standard secondary or triple drug immunosuppression (P=0.002).
the first in this trial: no signs of inflammatory response.
: No clinical infections with excessive immunosuppression were seen, which was previously assumed to be a safety issue.
the authors, Treg cells lose activation and even die within a few days without T-cells being stimulated by a T-cell body or CD28.
, only Treg clones that are stimulated by repeated antigens can maintain their inhibition and expand in the body.
third, the authors observed that the polyclonal T-cells of the infused Treg product changed over time in the body to oligoclonal patterns, indicating a selection process driven by isoid antigens.
Again, replacing anti-CD3/28 multiclonal antibodies with allogeneic antigens in inosometrific produces a biased T-cell-like genealogy within a few days, suggesting that there is a specific immunomodulation effect even after the injection of polyclonal nTregs.
, injections of nTreg only led to a temporary increase in Treg counts.
decrease in circulation after four weeks may be that nTregs concentrates on inflamed grafts or lacks long-lasting implants.
, the nTreg group expressed less conventional T-cell activation and natural killer cell maturation, which may indicate how nTreg works in the body.
important to emphasize is that the data in this trial show that nTregs combined with small doses of tekmos monotherapy does not adequately control pre-existing disease-dnogenic memory or effect immune cells.
hypothesis should be studied carefully in subsequent studies.
04, Treg therapy summary There are currently two main ways to make Treg cells: in vivo amplification of Treg cells and in vitro amplification of Treg cells under GMP conditions.
centers are focused on Treg's in-body amplification, and comparing data from both methods is critical to determining the best clinical use of Tregs.
in addition to the discussion of Treg heterogeneity will contribute to the development of clinical safety programmes.
key issue in the future will be immunosuppressive management in Treg cell therapy trials.
according to the transplant center's program, different patients currently receive different immunosuppressive programs (e.g., do not use steroids, delay the introduction of calcium-adjusted neurophosphatase inhibitors) in different doses.
these immunosuppressants are important when designing trials, as immunosuppression regulates the survival and function of Treg cells