specific tolerance
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2022 ◽  
Author(s):  
Braxton L. Jamison ◽  
James E. DiLisio ◽  
K. Scott Beard ◽  
Tobias Neef ◽  
Brenda Bradley ◽  
...  

The induction of antigen (Ag)-specific tolerance and replacement of islet β-cells are major ongoing goals for the treatment of Type 1 Diabetes (T1D). Our group previously showed that a hybrid insulin peptide (2.5HIP) is a critical autoantigen for diabetogenic CD4<sup>+</sup> T cells in the non-obese diabetic (NOD) mouse model. In this study, we investigated whether induction of Ag-specific tolerance using 2.5HIP-coupled tolerogenic nanoparticles (NPs) could protect diabetic NOD mice from disease recurrence upon syngeneic islet transplantation. Islet graft survival was significantly prolonged in mice treated with 2.5HIP NPs, but not NPs containing the insulin B chain peptide 9-23. Protection in 2.5HIP NP-treated mice was attributed both to the simultaneous induction of anergy in 2.5HIP-specific effector T cells and to the expansion of Foxp3+ regulatory T cells specific for the same antigen. Notably, our results indicate that effector function of graft-infiltrating CD4<sup>+</sup> and CD8<sup>+</sup> T cells specific for other β-cell epitopes was significantly impaired, suggesting a novel mechanism of therapeutically induced linked suppression. This work establishes that tolerance induction with a hybrid insulin peptide can delay recurrent autoimmunity in NOD mice, which could inform the development of an Ag-specific therapy for T1D.


2022 ◽  
Author(s):  
Braxton L. Jamison ◽  
James E. DiLisio ◽  
K. Scott Beard ◽  
Tobias Neef ◽  
Brenda Bradley ◽  
...  

The induction of antigen (Ag)-specific tolerance and replacement of islet β-cells are major ongoing goals for the treatment of Type 1 Diabetes (T1D). Our group previously showed that a hybrid insulin peptide (2.5HIP) is a critical autoantigen for diabetogenic CD4<sup>+</sup> T cells in the non-obese diabetic (NOD) mouse model. In this study, we investigated whether induction of Ag-specific tolerance using 2.5HIP-coupled tolerogenic nanoparticles (NPs) could protect diabetic NOD mice from disease recurrence upon syngeneic islet transplantation. Islet graft survival was significantly prolonged in mice treated with 2.5HIP NPs, but not NPs containing the insulin B chain peptide 9-23. Protection in 2.5HIP NP-treated mice was attributed both to the simultaneous induction of anergy in 2.5HIP-specific effector T cells and to the expansion of Foxp3+ regulatory T cells specific for the same antigen. Notably, our results indicate that effector function of graft-infiltrating CD4<sup>+</sup> and CD8<sup>+</sup> T cells specific for other β-cell epitopes was significantly impaired, suggesting a novel mechanism of therapeutically induced linked suppression. This work establishes that tolerance induction with a hybrid insulin peptide can delay recurrent autoimmunity in NOD mice, which could inform the development of an Ag-specific therapy for T1D.


2022 ◽  
Author(s):  
Gavin Robertson Meehan ◽  
Iain B McInnes ◽  
James M Brewer ◽  
Paul Garside

Currently, treatments for rheumatoid arthritis (RA) are focussed on treatment of disease symptoms rather than addressing the cause of disease, which could lead to remission and cure. Central to disease development is the induction of autoimmunity through a breach of self-tolerance. There is considerable research in RA focussed on antigens and approaches to re-establish antigen specific tolerance. A crucial step in this research is to employ appropriate animal models to test prospective antigen specific immunotherapies, preferably in the context of joint inflammation. In this short communication, we use our previously developed model of antigen specific inflammatory arthritis in which OVA-specific TcR tg T cells drive breach of tolerance to endogenous antigens to determine the impact that the timing of therapy administration has upon disease progression. Using antigen feeding to induce tolerance we demonstrate that administration prior to articular challenge results in a reduced disease score as evidenced by pathology and serum antibody responses. By contrast, feeding antigen after articular challenge had the opposite effect and resulted in the exacerbation of pathology. Although preliminary, these data suggest that the timing of antigen administration may be key to the success of tolerogenic immunotherapies. This has important implications for the timing of potential tolerogenic therapies in patients.


Diabetes ◽  
2022 ◽  
Author(s):  
Braxton L. Jamison ◽  
James E. DiLisio ◽  
K. Scott Beard ◽  
Tobias Neef ◽  
Brenda Bradley ◽  
...  

The induction of antigen (Ag)-specific tolerance and replacement of islet β-cells are major ongoing goals for the treatment of Type 1 Diabetes (T1D). Our group previously showed that a hybrid insulin peptide (2.5HIP) is a critical autoantigen for diabetogenic CD4+ T cells in the non-obese diabetic (NOD) mouse model. In this study, we investigated whether induction of Ag-specific tolerance using 2.5HIP-coupled tolerogenic nanoparticles (NPs) could protect diabetic NOD mice from disease recurrence upon syngeneic islet transplantation. Islet graft survival was significantly prolonged in mice treated with 2.5HIP NPs, but not NPs containing the insulin B chain peptide 9-23. Protection in 2.5HIP NP-treated mice was attributed both to the simultaneous induction of anergy in 2.5HIP-specific effector T cells and to the expansion of Foxp3+ regulatory T cells specific for the same antigen. Notably, our results indicate that effector function of graft-infiltrating CD4+ and CD8+ T cells specific for other β-cell epitopes was significantly impaired, suggesting a novel mechanism of therapeutically induced linked suppression. This work establishes that tolerance induction with a hybrid insulin peptide can delay recurrent autoimmunity in NOD mice, which could inform the development of an Ag-specific therapy for T1D.


2021 ◽  
Vol 20 (2) ◽  
pp. e898
Author(s):  
Adelodun L. Kolapo ◽  
Raoofat O. Salami ◽  
Gbemisola O. Onipede

The aim of this work was to report on molecular identification and technological properties of the yeast flora isolated from spontaneously fermented cassava waste pulp. This was done with a view of obtaining yeast strains that could be used as a starter culture for the fermentation of cassava waste pulp. Molecular identification was based on the nucleotide sequence of the ITS region of the genomic DNA of the yeast isolates while the technological properties evaluated include linamarase (U/mL), gelatinase, and haemolytic activity; growth at pH 2.5 and tolerance to 2 % bile salt. All the representative five isolated yeasts were identified as Geotrichum silvicola KLP04 – KLP08. The isolates exhibited linamarase activity ranging between 3.3 and 4.2 with strain KLP04 having the highest value and strain KLP05 the least. None of the isolates demonstrated gelatinase and haemolytic activity except strain KLP08 which was partially haemolytic. All the examined yeasts exhibited good growth at pH 2.5, with strain KLP08 having the highest viable counts of 4.1 log10cfu/ml and strain KLP04 the least value of 3.5 log10cfu/ml after 72 h of growth. All the identified yeasts showed strain-specific tolerance to 2% bile salt with strain KLP04 having the highest viable count of 4.3 log10cfu/ml and strain KLP08 the least value of 2.2 log10cfu/ml at the end of 72 h of incubation. Based on all the examined technological properties, Candida silvicola KLP04 strain had the highest potential to be considered for starter culture for the fermentation of cassava waste pulp.


PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0259114
Author(s):  
Beatriz Teresita Martín-Márquez ◽  
Minoru Satoh ◽  
Rogelio Hernández-Pando ◽  
Erika Aurora Martínez-García ◽  
Marcelo Heron Petri ◽  
...  

Introduction Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of autoantibodies such as anti-Sm. Studies in patients with SLE and murine models of lupus reveal that the most critical anti-Sm autoantibodies are predominantly direct against D1(83–119), D2, and B´/B epitopes. Objectives The present study aimed to analyze the induction of antigen-specific tolerance after prophylactic immunization with a DNA vaccine encoding the epitopes: D183-119, D2, B´/B, and B´/BCOOH in co-vaccination with IFN-γ or IL-10 in a murine model of lupus induced by pristane. Material and methods To obtain endotoxin-free DNA vaccines, direct cloning techniques using pcDNA were performed: D183-119, D2, B´/B, B´/BCOOH, IFN-γ, or IL-10. Lupus was induced by 0.5 mL of pristane via intraperitoneal in BALB/c female mice. Immunoprecipitation with K562 cells was metabolically labeled with 35S and ELISA to detect serum antibodies or mice IgG1, IgG2a isotypes. ELISA determined IL-10 and IFN-γ from splenocytes supernatants. Proteinuria was assessed monthly, and lupus nephritis was evaluated by immunofluorescence, and electron microscopy. Results The prophylactic co-vaccination with D2/IL-10 reduced the expression of kidney damage observed by electron microscopy, direct immunofluorescence, and H & E, along with reduced level of anti-nRNP/Sm antibodies (P = 0.048). Conclusion The prophylactic co-vaccination of IL-10 with D2 in pristane-induced lupus ameliorates the renal damage maybe by acting as prophylactic DNA tolerizing therapy.


2021 ◽  
Vol 17 (10) ◽  
Author(s):  
Rachel M. Ruden ◽  
James S. Adelman

Individuals can express a range of disease phenotypes during infection, with important implications for epidemics. Tolerance, in particular, is a host response that minimizes the per-pathogen fitness costs of infection. Because tolerant hosts show milder clinical signs and higher survival, despite similar pathogen burdens, their potential for prolonged pathogen shedding may facilitate the spread of pathogens. To test this, we simulated outbreaks of mycoplasmal conjunctivitis in house finches, asking how the speed of transmission varied with tissue-specific and behavioural components of tolerance, milder conjunctivitis and anorexia for a given pathogen load, respectively. Because tissue-specific tolerance hinders pathogen deposition onto bird feeders, important transmission hubs, we predicted it would slow transmission. Because behavioural tolerance should increase interactions with bird feeders, we predicted it would speed transmission. Our findings supported these predictions, suggesting that variation in tolerance could help identify individuals most likely to transmit pathogens.


KIDNEYS ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 130-136
Author(s):  
Yusuf Ercin Sonmez

A transplant between two people who are not genetically identical is called an allotransplant and the process is called allotransplantation. Donor organs and tissues can be from people who are living, or people who have died because of a significant brain injury or lack of circulation. Allotransplantation can create a rejection process where the immune system of the recipient attacks the foreign donor organ or tissue and destroys it. The recipient may need to take immunosuppressive medication for the rest of their life to reduce the risk of rejection of the donated organ. In general, deliberately induced immunosuppression is performed to prevent the body from rejecting an organ transplant. The adverse effects associated with these agents and the risks of long-term immunosuppression present a number of challenges for the clinician. Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that have the capacity to elicit an immune response in a given organism.


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