Is allergic disease curable or transferable with allogeneic hematopoietic cell transplantation?

Two cases of eosinophilic gastrointestinal disorder due to newly appearing food allergies after cord blood transplantation

Eosinophilic gastrointestinal disorders (EGIDs) are infrequent complications after allogeneic hematopoietic cell transplantation (allo-HCT). Furthermore, it is well-known that allergic diseases are transferable after allo-HCT from allergic donors to non-allergic recipients. However, the type of graft-versus host disease (GVHD) prophylaxis that leads to allergic disease transfer is unclear. Furthermore, no study has reported a case of acquired food allergy resulting in EGID that was detected based on the clinical course and the detection of antigen-specific immunoglobulin E after allo-HCT. We encountered two patients with acute leukemia accompanied by eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE) due to newly appearing food allergy after cord blood transplantation (CBT) with T-cell non-depletion GVHD prophylaxis. Despite having no history of allergic disease, the patients experienced allergic symptoms due to dairy products (Case 1) and eggs (Case 2) after CBT. They subsequently experienced severe nausea, heartburn, and anorexia (Case 1) and diarrhea (Case 2). Cases 1 and 2 were diagnosed with EoE and EGE, respectively, based on endoscopic and histological examinations. Dietary treatment without steroids improved the symptoms in both cases. These cases highlight that the unexpected transfer of food allergy after CBT can lead to EGIDs, especially in patients receiving T-cell non-depletion GVHD prophylaxis.

EDTA-induced pseudothrombocytopenia in hematopoietic stem cell donor

We herein report a case of peripheral blood stem cell transplantation (PBSCT) involving a donor with EDTA-induced pseudothrombocytopenia (PTCP). The apheresis product was inspected for 24 h and there was no platelet clumping or thrombocytopenia. In the first 14 months after PBSCT, there has been no transfer of PTCP symptoms.

The emerging role of nutritional support in the supportive care of pediatric patients undergoing hematopoietic stem cell transplantation

Allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) represents a potentially curative strategy for many oncological, hematological, metabolic, and immunological diseases in children. The continuous effort in ameliorating supportive care represents one of the cornerstones in the improvement of outcome in these patients. Nowadays, more than ever nutritional support can be considered a key feature. Oral feeding in the early post-transplant period is severely impaired because of mucositis due to conditioning regimen, characterized by, mainly by vomiting, anorexia, and diarrhea. Gastrointestinal acute graft-versus-host-disease (GvHD), infections and associated treatments, and other medications, such as opioids and calcineurin inhibitors, have also been correlated with decreased oral intake. The consequent reduction in caloric intake combined with the catabolic effect of therapies and transplantation-related complications with consequent extended immobilization, results in a rapid deterioration of nutritional status, which is associated with decreased overall survival and higher complication rates during treatment. Thus, nutritional support during the early post-transplantation period becomes an essential and challenging issue for allo-HSCT recipients. In this context, the role of nutrition in the modulation of the intestinal flora is also emerging as a key player in the pathophysiology of the main complications of HSCT. The pediatric setting is characterized by less evidence, considering the challenge of addressing nutritional needs in this specific population, and many questions are still unanswered. Thus, we perform a narrative review regarding all aspects of nutritional support in pediatric allo-HSCT recipients, addressing the assessment of nutritional status, the relationship between nutritional status and clinical outcomes and the evaluation of the nutritional support, ranging from specific diets to artificial feeding.

Frequent Eczematous Dermatitis in Unrelated Cord Blood Hematopoietic Cell Transplant Recipients Compared With Other Donor Types

We have consistently noticed in our clinical practice eczematous dermatitis (EcD) without other pathologic findings of graft-versus-host disease (GVHD) in recipients of unrelated cord blood transplantation (CBT). We hypothesized that the incidence of EcD was higher in CBT compared with other donor types, and our objective in this study was to compare the frequency, clinical course, and response to therapy of EcD between CBT and non-CBT recipients. We conducted a retrospective study of 720 consecutive adult recipients of allogeneic hematopoietic cell transplants from 2010 to 2016 from any donor type and with follow-up for at least 1 year after transplantation. After using keyword-based automated scanning to identify "eczema," "dermatitis," or "spongiosis" terms in medical records, we retrieved 217 cases for manual record review. We identified 23 EcD cases (12 in CBT recipients and 11 in patients with other types of donors) with a median onset at 8 months after transplantation. The 2-year cumulative incidence of EcD was 20% (95% confidence interval [CI], 11.2% to 31.5%) after CBT and 1.7% (95% CI, .90% to 2.90%) with other types of donors (P < .0001). Fifteen cases had a skin biopsy without distinctive pathologic features of GVHD. The most common EcD-involved sites in CBT recipients were face (75%), neck (50%), and antecubital fossae (50%). Compared with patients with other types of donors, EcD after CBT was more likely to involve three or more sites (10 of 12 vs. 2 of 10; P = .008) and had a more protracted course (lasting >6 months in 6 of 58 vs. 1 of 661; P < .0001). In both groups, EcD responded to topical therapy, and only a few cases required systemic therapy. EcD is a relatively frequent skin condition among recipients of unrelated CBT. Irrespective of donor type, most cases of EcD can be successfully managed with only topical therapy. These findings will help providers recognize EcD, avoid potentially harmful systemic therapy, and better counsel transplant recipients.

Mechanisms of human drug-induced anaphylaxis

Drug-induced anaphylaxis is a hyperacute reaction affecting multiple organs that can be of fatal consequence. Its incidence is increasing, consistent with a global increased sensitization to various allergens and drugs in the population. Few risk factors and mechanisms have been identified from human studies due to the rarity of anaphylactic events and their unpredictability. This systemic reaction is caused by the rapid release of a large range of functionally diverse mediators, including histamine and platelet-activating factor as the main drivers identified. Mechanisms defined from models of experimental anaphylaxis identify drug-specific antibodies of the IgE and IgG class that link the drug to antibody receptors on multiple cell types, causing their activation and mediator release. In the case of drugs with peculiar chemical structures, antibodies may not be necessary because drug-binding receptors, such as Mas-related G protein-coupled receptor member X2, have been identified. This review describes the complex reaction leading to drug-induced anaphylaxis that can involve various antibody classes, various cell types-including mast cells, neutrophils, platelets, basophils, macrophages, and monocytes-and their mediators and receptors that, importantly, can be activated alone or in association to participate in the severity of the reaction.

Post-transplant food anaphylaxis in an adult cord blood transplant recipient (Ms. No. IJHM-D-20-01037R1)

Transplant acquired food allergy (TAFA) is a well-known complication following pediatric liver transplantation, but post-cord blood transplantation (post-CBT) TAFA has rarely been reported. Here, we describe a case of new-onset food anaphylaxis after CBT in an adult patient that demonstrates that post-CBT allergen-challenge is not a risk for long-term allergic sensitization even in adult recipients. The patient was a 39-year-old Japanese man with aggressive NK cell leukemia. He had no previous history of allergies. After receiving CBT, the patient had an unbalanced diet with high preference for bread, bananas, miso-soup, cow's milk, cheese, egg, sesame and buckwheat soba noodles, and experienced repeated diarrhea. Six months later, he developed symptoms such as vomiting, epigastric pain, diarrhea, high fever and hypotension. The condition was initially diagnosed as enterocolitis, but symptoms recurred after consumption of buckwheat. Anaphylaxis induced by buckwheat was confirmed with serum radioallergosorbent tests (RAST), showing allergen-specific IgE for buckwheat (greater than 100 U/mL, Class 6) and egg ovomucoid (Class 4). Nineteen months after a buckwheat and egg-free diet, serum RAST for buckwheat and egg significantly improved. As a result, the patient acquired a tolerance and was able to consume buckwheat and egg without allergic symptoms.

Mito-managing ROS & redox to reboot the immune system: Tapping mitochondria & redox management to extend the reach of hematopoietic stem cell transplantation

Hematopoietic stem cells (HSCs) are responsible for life-long production of blood and immune cells. HSC transplantation (HSCT) is the original cell therapy which can cure hematological disorders but also has the potential to treat other diseases if technical and safety barriers are overcome. To maintain homeostatic hematopoiesis or to restore hematopoiesis during transplantation HSCs must perform both self-renewal, replication of themselves, and differentiation, generation of mature blood and immune cells. These are just two of the cell fate choices HSCs have; the transitional phases where HSCs undergo these cell fate decisions are regulated by reduction-oxidation (redox) signaling, mitochondrial activity, and cellular metabolism. Recent studies revealed that mitochondria, a key source of redox signaling components, are central to HSC cell fate decisions. Here we highlight how mitochondria serve as hubs in HSCs to manage redox signaling and metabolism and thus guide HSC fate choices. We focus on how mitochondrial activity is modulated by their clearance, biogenesis, dynamics, distribution, and quality control in HSCs. We also note how modulating mitochondria in HSCs can help overcome technical barriers limiting further use of HSCT.

Transfer and loss of allergen-specific responses via stem cell transplantation: A prospective observational study

BACKGROUND

Currently, no estimates can be made on the impact of hematopoietic stem cell transplantation on allergy transfer or cure of the disease. By using component-resolved diagnosis, we prospectively investigated 50 donor-recipient pairs undergoing allogeneic stem cell transplantation. This allowed calculating the rate of transfer or maintenance of allergen-specific responses in the context of stem cell transplantation.

METHODS

Allergen-specific IgE and IgG to 156 allergens was measured pretransplantation in 50 donors and recipients and at 6, 12 and 24 months in recipients post-transplantation by allergen microarray. Based on a mixed effects model, we determined risks of transfer of allergen-specific IgE or IgG responses 24 months post-transplantation.

RESULTS

After undergoing stem cell transplantation, 94% of allergen-specific IgE responses were lost. Two years post-transplantation, recipients' allergen-specific IgE was significantly linked to the pretransplantation donor or recipient status. The estimated risk to transfer and maintain individual IgE responses to allergens by stem cell transplantation was 1.7% and 2.3%, respectively. Allergen-specific IgG, which served as a surrogate marker of maintaining protective IgG responses, was highly associated with the donor's (31.6%) or the recipient's (28%) pretransplantation response.

CONCLUSION

Hematopoietic stem cell transplantation profoundly reduces allergen-specific IgE responses but also comes with a considerable risk to transfer allergen-specific immune responses. These findings facilitate clinical decision-making regarding allergic diseases in the context of hematopoietic stem cell transplantation. In addition, it provides prospective data to estimate the risk of transmitting allergen-specific responses via hematopoietic stem cell transplantation.

Management of allergy transfer upon solid organ transplantation

Allergy transfer upon solid organ transplantation has been reported in the literature, although only few data are available as to the frequency, significance, and management of these cases. Based on a review of 577 consecutive deceased donors from the Swisstransplant Donor-Registry, 3 cases (0.5%) of fatal anaphylaxis were identified, 2 because of peanut and 1 of wasp allergy. The sera of all 3 donors and their 10 paired recipients, prospectively collected before and after transplantation for the Swiss Transplant Cohort Study, were retrospectively processed using a commercial protein microarray fluorescent test. As early as 5 days posttransplantation, newly acquired peanut-specific IgE were transiently detected from 1 donor to 3 recipients, of whom 1 liver and lung recipients developed grade III anaphylaxis. Yet, to define how allergy testing should be performed in transplant recipients and to better understand the impact of immunosuppressive therapy on IgE sensitization, we prospectively studied 5 atopic living-donor kidney recipients. All pollen-specific IgE and >90% of skin prick tests remained positive 7 days and 3 months after transplantation, indicating that early diagnosis of donor-derived IgE sensitization is possible. Importantly, we propose recommendations with respect to safety for recipients undergoing solid-organ transplantation from donors with a history of fatal anaphylaxis.

Early emergence of anti-HCV antibody implicates donor origin in recipients of an HCV-infected organ

Hepatitis C virus (HCV) seroconversion among HCV-uninfected transplant recipients from HCV-infected (NAT+/Antibody+) or HCV-exposed (NAT-/Antibody+) donors has been reported. However, the origin of anti-HCV antibody and the implications of seroconversion remain unknown. We longitudinally tested plasma from HCV-uninfected kidney (n = 31) or heart transplant recipients (n = 9) of an HCV NAT+ organ for anti-HCV antibody (both IgG and IgM isotypes). Almost half of all participants had detectable anti-HCV antibody at any point during follow-up. The majority of antibody-positive individuals became positive within 1-3 days of transplantation, and 6 recipients had detectable antibody on the first day posttransplant. Notably, all anti-HCV antibody was IgG, even in samples collected posttransplant day 1. Late seroconversion was uncommon (≈20%-25% of antibody+ recipients). Early antibody persisted over 30 days in kidney recipients, whereas early antibody dropped below detection in 50% of heart recipients within 2 weeks after transplant. Anti-HCV antibody is common in HCV-uninfected recipients of an HCV NAT+ organ. The IgG isotype of this antibody and the kinetics of its appearance and durability suggest that anti-HCV antibody is donor derived and is likely produced by a cellular source. Our data suggest that transfer of donor humoral immunity to a recipient may be much more common than previously appreciated.

Surgical and immune reconstitution murine models in bone marrow research: Potential for exploring mechanisms in sepsis, trauma and allergy

Bone marrow, the vital organ which maintains lifelong hemopoiesis, currently receives considerable attention, as a source of multiple cell types which may play important roles in repair at distant sites. This emerging function, distinct from, but closely related to, bone marrow roles in innate immunity and inflammation, has been characterized through a number of strategies. However, the use of surgical models in this endeavour has hitherto been limited. Surgical strategies allow the experimenter to predetermine the site, timing, severity and invasiveness of injury; to add or remove aggravating factors (such as infection and defects in immunity) in controlled ways; and to manipulate the context of repair, including reconstitution with selected immune cell subpopulations. This endows surgical models overall with great potential for exploring bone marrow responses to injury, inflammation and infection, and its roles in repair and regeneration. We review three different murine surgical models, which variously combine trauma with infection, antigenic stimulation, or immune reconstitution, thereby illuminating different aspects of the bone marrow response to systemic injury in sepsis, trauma and allergy. They are: (1) cecal ligation and puncture, a versatile model of polymicrobial sepsis; (2) egg white implant, an intriguing model of eosinophilia induced by a combination of trauma and sensitization to insoluble allergen; and (3) ectopic lung tissue transplantation, which allows us to dissect afferent and efferent mechanisms leading to accumulation of hemopoietic cells in the lungs. These models highlight the gain in analytical power provided by the association of surgical and immunological strategies.

Decrease of Airway Allergies After Lung Transplantation Is Associated With Reduced Basophils and Eosinophils

BACKGROUND

Allergies are hypersensitive reactions of the immune system on antigen exposure similar to immune reactions after transplantation (Tx). Their activity can change after Tx. The lung as a transplantable organ is challenged two-fold, by antigens from the blood and the air environment. Herein we analyzed if airway allergies change after lung Tx.

METHODS

We systematically reviewed patients' airway allergies before and after lung Tx between 1992 and 2014. The course of lymphocytes, thrombocytes, and leukocytes, among them neutrophils, eosinophils, and basophils, was analyzed in patients in whom airway allergies have changed and in whom they did not change.

RESULTS

From 362 lung transplanted patients, 44 patients had suffered from allergies before Tx (12.2%). In 20 of these patients (45.5%), airway allergies disappeared completely within 1 year after lung Tx and were persistently absent thereafter. In these patients, basophils and eosinophils decreased significantly (P < .0012); in contrast, cells did not decrease in patients whose allergies did not disappear. Leukocytes overall, and in particular, neutrophils, decreased significantly in patients whose allergy disappeared (P < .014, P < .012, respectively).

CONCLUSIONS

Airway allergies disappeared in almost half of cases after lung Tx. Along with this reduction, basophils and eosinophils decreased as potentially responsible cells for this phenomenon. These findings may stimulate intensified research on basophils and eosinophils as major drivers of airway allergies.

A bacterial extract of OM-85 Broncho-Vaxom prevents allergic rhinitis in mice

BACKGROUND

According to the hygiene hypothesis, bacterial infections during early life contribute to a reduced incidence of asthma in animals. However, the effects of microbial products at a safe dose and within a rational time course on the prevention of allergic rhinitis (AR) have been inconclusive. This study investigated the immunomodulatory effects of oral administration of a bacterial extract, OM-85 Broncho-Vaxom (BV), with a low dose and general time course, which is currently used for respiratory infections in humans, on AR inflammation in mice.

METHODS

We developed a mouse model of ovalbumin (OVA)-induced AR allergic inflammation in the nose mucosa of mice. Low doses of OM-85 BV were orally administered for 3 months (long term) before sensitization. We evaluated nasal symptoms, pathology in the nose, inflammatory cells, and the levels of T helper 1 (Th1)/Th2 cytokines in the nasal lavage fluids, and the serum levels of specific IgE and IgG1. We also observed enhanced effects of OM-85 BV with 1 month (short term) of treatment.

RESULTS

We found that long-term pretreatment with OM-85 BV protected the mice from the majority of allergy-specific symptoms; specifically, OM-85 BV suppressed nasal symptoms, inhibited eosinophil infiltration in the nose, inhibited inflammatory infiltrates and the Th2 response by reducing cytokines (IL-4, IL-5, or IL-13) in the nasal lavage fluids, and reduced IgE and IgG1 levels. Furthermore, short-term treatment with OM-85 BV decreased the levels of Th2 cytokines and IgE.

CONCLUSION

Taken together, our data suggested that OM-85 BV is a low-cost alternative candidate to prevent AR with simple oral administration.

Transfer of peanut allergy following lung transplantation: a case report

This case study describes a patient who developed peanut allergy following lung transplantation. A 54-year-old woman underwent bilateral lung transplantation on June 2009 owing to severe chronic obstructive pulmonary disease. She had no history of food allergy before transplantation. The donor, however, was a 20-year-old man who was fatally injured during an automobile accident; he was allergic to peanuts. At 3 months after transplantation, the lung recipient presented with acute dyspnea and urticaria 15 minutes after consuming food containing peanut derivatives. Pre- and posttransplantation recipient blood samples analyzed for the presence of IgE antibodies specific for peanut allergens confirmed that the allergy had been passively transfered as a consequence of transplantation. Food allergy following solid organ transplantation is thought to be rare, mostly occurring in children. Two mechanisms may explain the observations described for the patient reported in this study: de novo development of peanut allergies after transplantation, or passive transfer of peanut allergies from a peanut-sensitized organ donor. This case report documenting pre- and posttransplantation IgE status in a lung transplantation case suggested that the allergic status of organ donors should be thoroughly assessed before transplantation, and potential allergy transfer risks must be discussed with the transplant team and the patient.

Cell-based therapy in allergy

IgE-mediated allergy is an immunological disorder occurring in response to otherwise harmless environmental antigens (i.e., allergens). Development of effective therapeutic or preventive approaches inducing robust tolerance toward allergens remains an unmet goal. Several experimental tolerance approaches have been described. The therapeutic use of regulatory T cells (Tregs) and the establishment of molecular chimerism are two cell-based strategies that are of particular interest. Treg therapy is close to clinical application, but its efficacy remains to be fully defined. Recent proof-of-concept studies demonstrated that transplantation of syngeneic hematopoietic stem cells modified in vitro to express a major allergen leads to molecular chimerism and robust allergen-specific tolerance. Here we review cell-based tolerance strategies in allergy, discussing their potentials and limitations.

Food allergy: transfused and transplanted

The inadvertent transfer of food allergy from an allergic donor to an unsuspecting recipient by transfusion or organ donation is a relatively rare but intriguing event with potentially catastrophic consequences. Additionally, the development of food allergy in the recipient of a transplant from a donor who was not food allergic poses questions about why this occurs, why it is observed more frequently in some situations than others, and the mechanisms that may be involved. In this review, the transfer of food allergy by transfusion, bone marrow transplantation, and the transplantation of different solid organs is explored, and potential mechanisms in addition to the importance of careful monitoring are discussed.