Type V collagen-induced nasal tolerance prevents lung damage in an experimental model: new evidence of autoimmunity to collagen V in COPD.

Background: Chronic obstructive pulmonary disease (COPD) has been linked to immune responses to lung-associated self-antigens. Exposure to cigarette smoke (CS), the main cause of COPD, causes chronic lung inflammation, resulting in pulmonary matrix (ECM) damage. This tissue breakdown exposes collagen V (Col V), an antigen typically hidden from the immune system, which could trigger an autoimmune response. Col V autoimmunity has been linked to several lung diseases, and the induction of immune tolerance can mitigate some of these diseases. Evidence suggests that autoimmunity to Col V might also occur in COPD; thus, immunotolerance to Col V could be a novel therapeutic approach. Objective: The role of autoimmunity against collagen V in COPD development was investigated by analyzing the effects of Col V-induced tolerance on the inflammatory response and lung remodeling in a murine model of CS-induced COPD. Methods: Male C57BL/6 mice were divided into three groups: one exposed to CS for four weeks, one previously tolerated for Col V and exposed to CS for four weeks, and one kept in clean air for the same period. Then, we proceeded with lung functional and structural evaluation, assessing inflammatory cells in bronchoalveolar lavage fluid (BALF) and inflammatory markers in the lung parenchyma, inflammatory cytokines in lung and spleen homogenates, and T-cell phenotyping in the spleen. Results: CS exposure altered the structure of elastic and collagen fibers and increased the pro-inflammatory immune response, indicating the presence of COPD. Col V tolerance inhibited the onset of emphysema and prevented structural changes in lung ECM fibers by promoting an immunosuppressive microenvironment in the lung and inducing Treg cell differentiation. Conclusion: Induction of nasal tolerance to Col V can prevent inflammatory responses and lung remodeling in experimental COPD, suggesting that autoimmunity to Col V plays a role in COPD development.

Large deletions and small insertions and deletions in the factor VIII gene predict unfavorable immune tolerance induction outcome in people with severe hemophilia A and high-responding inhibitors.

INTRODUCTION: Hemophilia A is an inherited bleeding disorder caused by pathogenic variants in the factor VIII gene (F8), which leads to factor VIII (FVIII) deficiency. Immune tolerance induction (ITI) is a therapeutic approach to eradicate alloantibodies (inhibitors) against exogenous FVIII in people with inherited hemophilia A. Few studies have evaluated the role of F8 variants on ITI outcome. MATERIAL AND METHODS: We included people with severe hemophilia A (FVIII ˂ 1 international units/dL) and high-responding inhibitors (≥ 5 Bethesda units/mL lifelong) who underwent a first course of ITI. Socio-demographic, clinical and laboratory data were collected. ITI outcomes were defined as total, partial successes, and failure. Detection of intron 1 and 22 inversions was performed by polymerase-chain reaction, followed by F8 sequencing. RESULTS: We included 168 people with inherited hemophilia A and high-responding inhibitors, median age 6 years at ITI start. Intron 22 inversion was the most prevalent variant (53.6 %), followed by nonsense (16.1 %), small insertion/deletion (11.3 %), and large deletion (10.7 %). In comparison with intron 22 inversion, the odds of ITI failure were 15.5 times higher (odds ratio [OR] 15.50; 95 % confidence interval [95 % CI] 4.59-71.30) and 4.25 times higher (95 % CI, 1.53-12.3) among carriers of F8 large deletions and small insertions and deletions, respectively. CONCLUSION: F8 large deletions and small insertions/deletions predicted ITI failure after a first course of ITI in patients with severe hemophilia A and high-responding inhibitors. This is the first study to show F8 large deletions and small insertions/deletions as predictors of ITI failure.

Clinical characteristics, laboratory findings, and tolerance acquisition in infants with cow's milk protein allergy in a private center in Lima, Peru for the period 2021-2022.

BACKGROUND: Cow's milk protein allergy (CMPA) remains relatively understudied in Latin America. METHODS: In this observational study, we enrolled 64 patients with a median age of 3 months, of whom 60% were male. Patients included had a history of IgE-mediated reactions with IgE sensitization or non-IgE-mediated reactions or symptoms following exposure to cow's milk. They underwent skin prick test, ImmunoCAP, fecal calprotectin (FC), and fecal eosinophil-derived neurotoxin (EDN), in addition to double-blinded placebo-controlled oral food challenges (DBPCFC), with clinical evolution and tolerance acquisition observed over 1 year. RESULTS: Malnutrition was present in 78.1% of patients, and 87.5% had a family history of atopy, with 51.6% receiving exclusive breastfeeding. Gastrointestinal manifestations were prevalent in 90.6% of patients, followed by dermatological manifestations (10.9%), with only 2 experiencing anaphylaxis. IgE-mediated CMPA was observed in only six patients. In those with non-IgE-mediated CMPA, FC had a median of 284 mg/dL (IQR: 138.5-415.5), while EDN had a median of 508.5 mg/dL (IQR: 160.25-868). One year after diagnosis, median FC significantly decreased (p < 0.0001), and malnutrition prevalence reduced to 17.1%. Moreover, 81% of patients acquired tolerance following DBPCFC, with 52% utilizing nutritional replacement formulas at diagnosis. Notably, 94% of those extensively hydrolyzed casein-based formulas achieved tolerance (p = 0.08). CONCLUSION: Our findings provide a foundational framework for future investigations into CMPA diagnosis, tolerance acquisition, and the utilization of hypoallergenic formulas tailored to the unique characteristics of our region.

Presence of Epstein-Barr virus (EBV) antigens detected by sensitive methods has no influence on local immune environment in diffuse large B cell lymphoma.

EBV+ diffuse large B cell lymphoma (DLBCL) not otherwise specified (NOS) is a new entity confirmed by the World Health Organization (WHO) in 2017. In this new entity, the virus may contribute to a tolerogenic microenvironment. Traces of the virus have been described in DLBCL with more sensitive methods, in cases that were originally diagnosed as negative. The aim of this study was to analyze the expression of immune response genes in the tumor microenvironment to disclose the role of the virus and its traces in DLBCL. In 48 DLBCL cases, the expression of immune response genes and the presence of molecules that induce tolerance, such as TIM3, LAG3 and PDL1 by immunohistochemistry (IHC), were studied. To broaden the study of the microenvironment, tumor-associated macrophages (TMAs) were also explored. No significant differences were observed in the expression of immune response genes in the EBV+ DLBCL and those cases that were EBV- DLBCL but that exhibited viral traces, assessed by ViewRNA assay. Only the EBV+ DLBCL cases displayed a significantly higher increase in the expression of CD8 and cytotoxic T cells detected by gene expression analysis, and of PDL1 in tumor cells and in the expression of CD68 in the tumor microenvironment detected by IHC, not observed in those cases with viral traces. The increase in CD8 and cytotoxic T cells, PDL1 and CD68 markers only in EBV+ DLBCL may indicate that traces of viral infection might not have influence in immune response markers.

Tumor metabolic crosstalk and immunotherapy.

Tumor cells must resist the host's immune system while maintaining growth under harsh conditions of acidity and hypoxia, which indicates that tumors are more robust than normal tissue. Immunotherapeutic agents have little effect on solid tumors, mostly because of the tumor density and the difficulty of penetrating deeply into the tissue to achieve the theoretical therapeutic effect. Various therapeutic strategies targeting the tumor microenvironment (TME) have been developed. Immunometabolic disorders play a dominant role in treatment resistance at both the TME and host levels. Understanding immunometabolic factors and their treatment potential may be a way forward for tumor immunotherapy. Here, we summarize the metabolism of substances that affect tumor progression, the crosstalk between the TME and immunosuppression, and some potential tumor-site targets. We also summarize the progress and challenges of tumor immunotherapy.

Mucormicosis oral asociada a COVID-19 y diabetes mellitus: descripción de un caso / Oral mucormycosis associated with COVID-19 and diabetes mellitus: Case report and literature review

La mucormicosis es una infección fúngica oportunista e invasiva, con una elevada tasa de mortalidad. Se ha detectado principalmente en pacientes con COVID-19, especialmente en personas con enfermedades concomitantes como la diabetes mellitus. La prevalencia de las mucormicosis es de 0,005 a 1,7 casos por millón de habitantes y ha ido en aumento en países como India y Pakistán; puede afectar diferentes órganos y su forma clínica refleja el mecanismo de transmisión. Entre las formas frecuentes están la rino-orbital-cerebral y la pulmonar, por ello, debe sospecharse mucormicosis en los pacientes con lesiones necróticas en mucosas o piel. Se presenta el caso de un paciente con antecedentes de diabetes mellitus que fue diagnosticado con mucormicosis oral asociada a la COVID-19.

Mucormycosis is an invasive opportunistic fungal infection with high mortality, mainly detected in people with COVID-19, especially those with underlying diseases such as diabetes mellitus. Mucormycosis prevalence is 0.005 to 1.7 cases per million inhabitants, and it has been increasing in countries like India and Pakistan. This mycosis can affect different organs, and clinical manifestations reflect the transmission mechanism. Frequent forms are rhino-orbital-cerebral and pulmonary. This disease should be suspected in patients with necrotic injuries on mucous membranes or skin. We present a case of a patient with diabetes mellitus and diagnosed with oral mucormycosis associated with COVID-19.

Inducción de tolerancia inmune en menores de 18 años con hemofilia A: experiencia en Uruguay, 2009-2020 / Induction of immune tolerance in children of under 18 years of age with hemophilia A: experience in uruguay, 2009-2020 / Indução de tolerância imune em crianças menores de 18 anos com hemofilia A: experiência no uruguai, 2009-2020

Introducción: el desarrollo de inhibidores contra el factor VIII (FVIII) es la complicación más seria del tratamiento en la hemofilia A. La inducción de tolerancia inmune (ITI) permite utilizar nuevamente el concentrado de FVIII para profilaxis o tratamiento. Objetivos: describir la experiencia con la ITI en menores de 18 años con hemofilia A severa (HAS) en un prestador integral de salud pública. Material y métodos: estudio descriptivo, retrospectivo, de menores de 18 años con HAS, concentraciones de inhibidores de FVIII ≥ a 5 UB, a quienes se les realizó ITI y seguimiento completo entre 2009 y 2020. Para la ITI se utilizó concentrado de FVIII derivado plasmático. El beneficio se expresa como la tasa de éxito definido por la negativización del inhibidor. Resultados: se incluyeron seis pacientes. Edad promedio al diagnóstico de inhibidor 2,96 años, luego de 24,4 días de exposición (DDE) a concentrados de FVIII. Media de inicio de ITI 3,76 niños y el tiempo de latencia del diagnóstico de inhibidor y el inicio de la ITI fue de 10,33 meses. El pico máximo del título pre-ITI fue en promedio de 114,7 UB. Cuatro pacientes iniciaron el régimen de ITI con títulos de inhibidor menor a 10 UB. El título del inhibidor se negativizó en 8,2 meses y el porcentaje de recuperación in vivo >65% se logró con una media de 15,7 meses. La ITI fue exitosa en 83% de los casos. Conclusiones: en niños con hemofilia A e inhibidores de alto título, la ITI tiene un elevado éxito, tal como ocurrió en esta serie. Dado que el tiempo de respuesta es variable, la ITI debe ser individualizada.

Introduction: the development of inhibitors against factor VIII is the most serious complication of treatment in hemophilia A. Immune tolerance induction (ITI) enables the factor VIII concentrate to be used again for prophylaxis or treatment. Objectives: describe the experience with ITI in children of under 18 years of age with severe hemophilia A (SAH) in a health care provider. Material and methods: descriptive, retrospective study of children under 18 years of age with SAH, concentrations of FVIII inhibitors ≥ 5BU, who underwent ITI and full follow-up between 2009-2020. For ITI, we used plasma derived FVIII concentrate. The benefit is expressed as the success rate defined by the inhibitor's negativization. Results: 6 patients were included. Mean age at diagnosis of inhibitor 2,96 years, after 24,4 days of exposure (DAE) to FVIII concentrates. Mean ITI onset was 3,76 years and latency time from inhibitor diagnosis and ITI onset was 10,33 months. Maximum peak of the pre ITI title was an average of 114,7 UB. Four patients started the ITI regimen with inhibitors titers less than 10 BU. The inhibitor titer negative in 8,2 months and in vivo recovery rate >65% was achieved with a mean of 15,7 months. The ITI was successful in 83% of the cases. Conclusions: ITI is highly successful in children with hemophilia A and high-titer inhibitors, as this case suggests. Since the response time is variable, the ITI must be individualized.

Introdução: o desenvolvimento de inibidores contra o fator VIII é a complicação mais grave do tratamento da hemofilia A. A indução de tolerância imunológica (ITI) permite que o concentrado de fator VIII seja novamente utilizado para profilaxia ou tratamento. Objetivos: descrever a experiência com ITI em crianças menores de 18 anos com hemofilia A grave (HAS) em um serviço de saúde pública abrangente. Material e métodos: estudo descritivo e retrospectivo de crianças menores de 18 anos com HAS, concentrações de inibidor do FVIII ≥ 5 BU), que realizaram ITI e acompanhamento completo entre 2009-2020. Concentrado de FVIII derivado de plasma foi utilizado para ITI. O benefício é expresso como a taxa de sucesso definida pela negativação do inibidor. Resultados: 6 pacientes foram incluídos. Idade média no diagnóstico do inibidor 2,96 anos, após 24,4 dias de exposição (DDE) a concentrados de FVIII. A média de início da ITI foi de 3,76 crianças e o tempo de latência do diagnóstico do inibidor e início da ITI foi de 10,33 meses. O pico máximo do título pré-ITI foi em média 114,7 BU. Quatro pacientes iniciaram o regime ITI com títulos de inibidor inferiores a 10 BU. O título do inibidor tornou-se negativo em 8,2 meses e a percentagem de recuperação in vivo >65% foi alcançada com uma média de 15,7 meses. O ITI foi bem-sucedido em 83% dos casos. Conclusões: em crianças com hemofilia A e inibidores de títulos elevados, a ITI é altamente bem sucedida, como ocorreu nesta série. Como o tempo de resposta é variável, o ITI deve ser individualizado.

Mechanism underlying polyvalent IgG-induced regulatory T cell activation and its clinical application: Anti-idiotypic regulatory T cell theory for immune tolerance.

The regulatory T (Treg) cells constitute a functionally defined subpopulation of T cells that modulate the immune system and maintain immune tolerance through suppression of the development of autoimmune responses to self-antigens and allergic reactions to external antigens. Reduction in the number or function of Treg cells has been suggested as a key immune abnormality underlying the development of autoimmune and allergic diseases. In vitro studies have demonstrated that purified polyvalent immunoglobulin G (IgG) from multiple healthy blood donors can exert immunomodulatory effects on Treg cells. Incubation of polyvalent human IgG with purified CD4+CD25high T cells increased the intracellular expression of interleukin (IL)-10. Intravenous administration of polyvalent human IgG induced significant expansions of CD4+ Foxp3+ Treg cells and clinical improvements in patients with autoimmune diseases. In human clinical trials, intramuscular administration of autologous total IgG significantly increased the percentage of IL-10-producing CD4+ Treg cells in the peripheral blood of healthy subjects and provided significant clinical improvements in patients with atopic dermatitis. These results suggest a clinical usefulness of polyvalent IgG-induced activation of Treg cells in human subjects. This review proposes a new hypothesis for immune tolerance mechanism by integrating the pre-existing "idiotypic network theory" and "Treg cell theory" into an "anti-idiotypic Treg cell theory." Based on this hypothesis, an "active anti-idiotypic therapy" for allergic and autoimmune diseases using autologous polyvalent IgG (as immunizing antigens) is suggested as follows: (1) Intramuscular or subcutaneous administration of autologous polyvalent IgG produces numerous immunogenic peptides derived from idiotypes of autologous IgG through processing of dendritic cells, and these peptides activate anti-idiotypic Treg cells in the same subject. (2) Activated anti-idiotypic Treg cells secrete IL-10 and suppress Th2 cell response to allergens and autoimmune T cell response to self-antigens. (3) These events can induce a long-term clinical improvements in patients with allergic and autoimmune diseases. Further studies are needed to evaluate the detailed molecular mechanism underlying polyvalent IgG-induced Treg cell activation and the clinical usefulness of this immunomodulatory therapy for autoimmune and allergic diseases.

Genes, inflammatory response, tolerance, and resistance to virus infections in migratory birds, bats, and rodents.

Normally, the host immunological response to viral infection is coordinated to restore homeostasis and protect the individual from possible tissue damage. The two major approaches are adopted by the host to deal with the pathogen: resistance or tolerance. The nature of the responses often differs between species and between individuals of the same species. Resistance includes innate and adaptive immune responses to control virus replication. Disease tolerance relies on the immune response allowing the coexistence of infections in the host with minimal or no clinical signs, while maintaining sufficient viral replication for transmission. Here, we compared the virome of bats, rodents and migratory birds and the molecular mechanisms underlying symptomatic and asymptomatic disease progression. We also explore the influence of the host physiology and environmental influences on RNA virus expression and how it impacts on the whole brain transcriptome of seemingly healthy semipalmated sandpiper (Calidris pusilla) and spotted sandpiper (Actitis macularius). Three time points throughout the year were selected to understand the importance of longitudinal surveys in the characterization of the virome. We finally revisited evidence that upstream and downstream regulation of the inflammatory response is, respectively, associated with resistance and tolerance to viral infections.

COVID-19 en las embarazadas. Riesgo de las complicaciones durante el embarazo y en el neonato / COVID-19 in pregnant women. Risk of complications during pregnancy and in the newborn

Sobre el tema COVID-19 se han publicado múltiples estudios que reflejan su elevada incidencia, transmisibilidad, morbilidad y mortalidad, con gran repercusión y severidad en los grupos poblacionales de riesgo. El embarazo no escapa a ello, y la inmunosupresión fisiológica que se presenta en esta condición, hace a la gestante y al neonato, ser más susceptibles a las enfermedades infecciosas. El objetivo de esta comunicación es profundizar en la fisiopatología y la repercusión de la enfermedad COVID-19 en las gestantes y el neonato, para mejorar el conocimiento relacionado con el tema, el cual repercutirá en un mejor manejo de estos pacientes. Para ello, se realizó una revisión de investigaciones publicadas en el período comprendido entre enero y diciembre de 2021, en las bases de datos: SciELO, SCOPUS, Medline, Dialnet, Cumed y Lilacs. De los 44 artículos obtenidos inicialmente, 33 cumplieron los criterios de inclusión.

Several studies on COVID-19 have been published reflecting its high incidence, transmissibility, morbidity and mortality, with great repercussions and severity in population groups at risk. Pregnancy does not escape from this, and the physiological immunosuppression that occurs in this condition makes the pregnant woman and the newborn more susceptible to infectious diseases. The objective of this communication is to deepen the pathophysiology and the repercussion of the COVID-19 disease in pregnant women and the newborn in order to improve knowledge related to the subject, which will have an impact on better management of these patients. For this, a review of research published between January and December 2021 was carried out in the databases such as SciELO, SCOPUS, Medline, Dialnet, Cumed and Lilacs. A number of 33 articles met the inclusion criteria from 44 initially obtained.

Obesity-induced hyperglycemia impairs oral tolerance induction and aggravates food allergy.

Obesity and type 2 diabetes (T2D) have been found to be associated with abnormalities in several organs, including the intestine. These conditions can lead to changes in gut homeostasis, compromising tolerance to luminal antigens and increasing susceptibility to food allergies. The underlying mechanisms for this phenomenon are not yet fully understood. In this study, we investigated changes in the intestinal mucosa of diet-induced obese mice and found that they exhibited increased gut permeability and reduced Treg cells frequency. Upon oral treatment with ovalbumin (OVA), obese mice failed to develop oral tolerance. However, hyperglycemia treatment improved intestinal permeability and oral tolerance induction in mice. Furthermore, we observed that obese mice exhibited a more severe food allergy to OVA, and this allergy was alleviated after treatment with a hypoglycemic drug. Importantly, our findings were translated to obese humans. Individuals with T2D had higher serum IgE levels and downregulated genes related to gut homeostasis. Taken together, our results suggest that obesity-induced hyperglycemia can lead to a failure in oral tolerance and to exacerbation of food allergy. These findings shed light on the mechanisms underlying the relationship among obesity, T2D, and gut mucosal immunity, which could inform the development of new therapeutic approaches.

[Basophil activation test to follow-up of patients treated with hymenoptera venom immunotherapy: a review of current evidence]. / Prueba de activación de basófilos en el seguimiento de pacientes que reciben inmunoterapia con veneno de himenópteros: revisión de la evidencia actual.

Hymenoptera venom immunotherapy (HVI) is a long-term effective treatment to avoid new systemic reactions in patients with Hymenoptera allergy. The sting challenge test is considered the gold standard to confirm the tolerance. However, the use of this technique is not generalized in clinical practice, being the basophil activation test (BAT), which functionally explores allergen response, an alternative that does not entail any of the provocation risks associated with the sting challenge test. This study reviews the publications that used the BAT to follow up and evaluate the success of the HVI. Studies assessing the changes between a baseline BAT before the start and BATs performed between the starting and maintenance phases of the HVI were selected. Ten articles were found, comprising information from 167 patients, of which 29% used the sting challenge test. The studies concluded the importance of evaluating the responses with submaximal allergen concentrations, which reflect basophil sensitivity, to monitor the HVI using the BAT. It was also observed that changes in the maximum response (reactivity) could not reflect the clinical status of tolerance, particularly in the initial phases of HVI.

La inmunoterapia con veneno de himenópteros (IVH) es, a largo plazo, un tratamiento eficaz para evitar nuevas reacciones sistémicas en pacientes con alergia a este tipo de insectos. La prueba de repicadura controlada es el estudio de referencia para confirmar la tolerancia del individuo. Sin embargo, no se ha generalizado su indicación clínica, por lo que la prueba de activación de basófilos (TAB) resulta una buena alternativa, pues valora de manera funcional la respuesta al alérgeno y está exenta de los riesgos asociados con la provocación. En esta revisión se explora la utilidad de la TAB en el seguimiento y valoración del éxito de la IVH. Se seleccionaron estudios que evalúan los cambios entre una TAB basal y en otro momento de la fase de inicio o mantenimiento de la IVH. Se incluyeron 10 estudios con datos de 167 pacientes, de los que el 29% había tenido prueba de repicadura controlada. Para vigilar la eficacia de la IVH debe explorarse la respuesta del basófilo, con la determinación de las concentraciones submáximas del alérgeno, que reflejan la sensibilidad del basófilo. Los cambios en la respuesta máxima (reactividad) no pueden aportar información del estado de tolerancia, especialmente en las fases iniciales de la IVH.

Fetal allotransplant recipients are resistant to graft-versus-host disease.

In utero hematopoietic cell transplantation (IUHCT) is an experimental treatment for congenital hemoglobinopathies, including Sickle cell disease and thalassemias. One of the principal advantages of IUHCT is the predisposition of the developing fetus toward immunologic tolerance. This allows for engraftment across immune barriers without immunosuppression and, potentially, decreased susceptibility to graft-versus-host disease (GVHD). We demonstrate fetal resistance to GVHD following T cell-replete allogeneic hematopoietic cell transplantation compared with the neonate. We show that this resistance is associated with elevated fetal serum interleukin-10 conducive to the induction of regulatory T cells (Tregs). Finally, we demonstrate that the adoptive transfer of Tregs from IUHCT recipients to neonates uniformly prevents GVHD, recapitulating the predisposition to tolerance observed after fetal allotransplantation. These findings demonstrate fetal resistance to GVHD following hematopoietic cell transplantation and elucidate Tregs as important contributors.

Immunotolerance in liver transplantation: a primer for the clinician.

The use of immunosuppressive medications for solid organ transplantation is associated with cardiovascular, metabolic, and oncologic complications. On the other hand, the development of graft rejection is associated with increased mortality and graft dysfunction. Liver transplant recipients can withdraw from immunosuppression without developing graft injury while preserving an adequate antimicrobial response - a characteristic known as immunotolerance. Immunotolerance can be spontaneously or pharmacologically achieved. Contrary to the classic dogma, clinical studies have elucidated low rates of true spontaneous immunotolerance (no serologic or histological markers of immune injury) among liver transplant recipients. However, clinical, serologic, and tissue biomarkers can aid in selecting patients in whom immunosuppression can be safely withdrawn. For those who failed an immunosuppression withdrawal trial or are at high risk of rejection, pharmacological interventions for immunotolerance induction are under development. In this review, we provide an overview of the mechanisms of immunotolerance, the clinical studies investigating predictors and biomarkers of spontaneous immunotolerance, as well as the potential pharmacological interventions for inducing it.

Therapeutic Opportunities for Immunoreceptor-Engineered T Cell Therapy for Modulation of Alloimmunity.

Achieving immunosuppression-free immune tolerance to an allograft is one of the central goals of transplantation. In this article, we review recent developments in the fields of T cell-based therapies and T cell engineering using chimeric Ag receptors and their potential for effective and targeted immune modulation of T and B cell activity in an effort to eliminate pre-existing alloantibodies (desensitization) and achieve long-term tolerance. Approaches that span preclinical to early clinical studies in transplantation will be reviewed, with specific emphasis on advances in T cell immunotherapy that have shown promise. Lastly, we conclude with a forward-looking discussion of how T cell-based therapies in other fields of medicine can be potentially applied to solid organ transplantation.