Evidence-Based Minireview: In young children with severe sickle cell disease, do the benefits of HLA-identical sibling donor HCT outweigh the risks?

In case 1, a 14-month-old male child with sickle cell disease (SCD) was referred for evaluation for an allogeneic hematopoietic stem cell transplant (HCT). The patient had a history of dactylitis 3 times in his first year of life and febrile episodes twice at the consult. His 4-year-old sister was found to be human leukocyte antigen (HLA) identical. The patient was started on hydroxyurea (HU) at 2.5 years of age. His parents again sought consultation when he was 5 years old because of concerns about his medical condition. At the time, the patient had experienced 2 vaso-occlusive pain episodes (VOEs) requiring hospitalization during the previous 2 years. He had also experienced intermittent pain crises requiring rest at home for 2 to 3 days. The child has not attended school in person due to the COVID-19 pandemic. The family is considering HCT but is ambivalent about it because of potential toxicity. In case 2, an 8-year-old female child is 3 years out from HCT for SCD from her HLA-identical sibling. Before HCT, despite receiving HU, she had experienced >5 VOEs requiring hospitalization and 2 episodes of acute chest syndromes in the previous 3 years. She had also been missing almost 50 days of school days each year. After HCT, she is now attending school regularly and participating in all normal age-appropriate activities. The parents believe that HCT has been transformative in their child's life.

Diagnostic work-up for severe aplastic anemia in children: Consensus of the North American Pediatric Aplastic Anemia Consortium.

The North American Pediatric Aplastic Anemia Consortium (NAPAAC) is a group of pediatric hematologist-oncologists, hematopathologists, and bone marrow transplant physicians from 46 institutions in North America with interest and expertise in aplastic anemia, inherited bone marrow failure syndromes, and myelodysplastic syndromes. The NAPAAC Bone Marrow Failure Diagnosis and Care Guidelines Working Group was established with the charge of harmonizing the approach to the diagnostic workup of aplastic anemia in an effort to standardize best practices in the field. This document outlines the rationale for initial evaluations in pediatric patients presenting with signs and symptoms concerning for severe aplastic anemia.

Optimizing conditioning regimen with low-dose irradiation or busulfan enables the outcome of transplantation from a 6-7/8 HLA-matched donor comparable to that from an 8/8 HLA-matched unrelated donor in severe aplastic anemia patients under 40 years.

With the dramatic improvements in outcomes following alternative donor hematopoietic stem cell transplantation (HSCT), interest in the use of alternative donors in severe aplastic anemia (SAA) is increasing. We conducted a multicenter prospective study to explore the efficiency and safety of upfront HSCT from a 6-8/8 HLA-matched unrelated donor (MUD) or 6-7/8 HLA-matched related donor (MRD) in acquired SAA patients under 40 years. Between August 2014 and July 2017, 115 patients were enrolled, including 48 (41.7%) patients receiving grafts from an 8/8 MUD, 25 (21.7%) from a 6-7/8 MRD, and 42 (36.5%) from a 6-7/8 MUD. The incidence of grade II-IV acute graft-versus-host disease (GVHD) was higher in the 6-7/8 MUD group than in the 8/8 MUD group (42.9% vs. 12.8%, P=0.001). The corresponding incidence in the 6-7/8 MRD group was comparable to that in the 8/8 MUD group (21.7% vs. 12.8%, P=0.332). There was no significant difference in the incidence of chronic GVHD (24.3%, 13.6%, and 17.9%, P=0.676), graft failure (2.4%, 8.0%, and 6.3%, P=0.551), overall survival (85.7%, 96.0%, and 87.5%, P=0.424), and failure-free survival (83.3%, 88.0%, and 83.3%, P=0.885) among the three groups (6-7/8 MUD, 6-7/8 MRD, and 8/8 MUD). In multivariate analysis, conditioning regimen without low-dose irradiation or busulfan was associated with an inferior failure-free survival (HR=2.973, P=0.042). In conclusion, after an intensified conditioning regimen with additional low-dose irradiation or busulfan, the outcome of HSCT from a 6-7/8 MRD or 6-7/8 MUD is comparable to that from an 8/8 MUD.

Transfusion burden following reduced intensity allogeneic hematopoietic cell transplantation: Impact of donor type.

BACKGROUND: Transfusions are essential for allogeneic hematopoietic cell transplant (HCT), yet they are influenced by graft, donor, and other factors. STUDY DESIGN: We analyzed transfusions in 165 adult reduced intensity HCTs (2016-2019): HLA matched sibling donor (MSD) (n = 59), matched URD (n = 25), UCB (n = 33), and haploidentical (haplo, n = 48) detailing the cumulative incidence of platelet and RBC transfusion independence, total transfusions (day-10 to day+100) plus transfusion densities (per week) over 110 days. RESULTS: Platelet recovery to 20 × 109 /L by 6 months occurred in 39/48 (81.25%) haplo recipients (median 33 [range, 0-139]) days vs. 58/59 (98.3%) MSD (median 10 [0-37]), 21/25 (84%) matched URD (median 20 [0-153]), and 29/33 (87.87%) UCB (median 48 [29-166]) days, p < .01. Regression analysis demonstrated a lower likelihood of prompt platelet recovery in matched URD, UCB, or haplo HCTs vs. MSD. Recovery to platelet independence was quickest in MSD (median 8 days [range 0-94]), vs. URD (median 16 days [0-99]), UCB (median 57 [0-94]), or haplo (median 45 [12-97]) days, p < .01. Platelet needs were unaffected by age, conditioning, or acute GVHD. RBC transfusion independence was achieved in 78% of MSD, 64% URD, and 82% UCB, though less frequent (58%) and slowest in haplo recipients, p < .01. All haplo and UCB recipients required platelet transfusions vs. only 51% of MSD and 76% of URD. RBC needs were highest in UCB and haplo HCTs. DISCUSSION: The transplant donor influences the transfusion burden with greater platelet and RBC needs in haplo and UCB HCT which directly contributes to increased cost of care.

Identification of bacteria-derived HLA-bound peptides in melanoma.

A variety of species of bacteria are known to colonize human tumours1-11, proliferate within them and modulate immune function, which ultimately affects the survival of patients with cancer and their responses to treatment12-14. However, it is not known whether antigens derived from intracellular bacteria are presented by the human leukocyte antigen class I and II (HLA-I and HLA-II, respectively) molecules of tumour cells, or whether such antigens elicit a tumour-infiltrating T cell immune response. Here we used 16S rRNA gene sequencing and HLA peptidomics to identify a peptide repertoire derived from intracellular bacteria that was presented on HLA-I and HLA-II molecules in melanoma tumours. Our analysis of 17 melanoma metastases (derived from 9 patients) revealed 248 and 35 unique HLA-I and HLA-II peptides, respectively, that were derived from 41 species of bacteria. We identified recurrent bacterial peptides in tumours from different patients, as well as in different tumours from the same patient. Our study reveals that peptides derived from intracellular bacteria can be presented by tumour cells and elicit immune reactivity, and thus provides insight into a mechanism by which bacteria influence activation of the immune system and responses to therapy.

Toxic epidermal necrolysis in a patient on atorvastatin therapy expressing human leukocyte antigen alleles: A case report.

RATIONALE: Toxic epidermal necrolysis (TEN) is a rare, severe mucosal response of the skin associated with a high mortality rate. TEN is most commonly caused by drugs, and is characterized by extensive skin epidermal exfoliation. PATIENT CONCERNS: A 68-year-old woman presented with a rash that had persisted for four days. The patient who had undergone a mitral valve replacement 1 month prior and was taking atorvastatin at the time of admission. DIAGNOSES: The patient exhibited more than 30% exfoliation surfaces and the severe drug eruption was considered to be TEN. According to human leukocyte antigen (HLA) allele detection and ALDEN score, HLA alleles which found in this case report may be an cause of TEN induced by atorvastatin. INTERVENTIONS: All drugs used prior to admission were discontinued and the patient was given antiallergic drugs. OUTCOMES: After 3 weeks following Antiallergic treatment, the rash on patient's calf had subsided, the edema was relieved, and the patient was no longer experiencing pain. After 60 days following discharge, the patient's skin has regrown. LESSONS: This is the first report describing the induction of TEN by atorvastatin in a HLA alleles carrier. For HLA alleles carrier, atorvastatin may need to be used with caution to avoid TEN. Future systematic research is also required to confirm this finding and avoid similar serious skin adverse reactions.

Development of a humanized mouse model to analyze antibodies specific for human leukocyte antigen (HLA).

In organ transplantation, human leukocyte antigen (HLA)-mismatch grafts not only induce the activation of cellular mediated immune response but also the development of chronic antibody-mediated rejection due to the donor-specific anti-HLA antibody (DSA) produced by B cells and plasma cells interacting with the graft endothelium. Significant improvement in long-term survival after transplantation can be expected if antibody-mediated rejection due to the DSA can be overcome. However, the mechanism of producing or controlling the DSA remains to be elucidated. In recent decades, "humanized" mouse models have been widely used for the basic research of human immune systems, but a humanized mouse model to analyze the mechanism of DSA production has not been established yet. Thus, we aimed to create a humanized mouse using a severe immunodeficiency mouse (NSG mouse) administered with human peripheral blood mononuclear cells (PBMCs). Initially, we detected a very low level of human total-IgG and no anti-HLA antibodies (Abs) in these mice. In our next attempt, we mixed PBMCs of various HLA antigenic combinations with or without regulatory T cells and preconditioned them by culturing on feeder cells stably transfected with human CD40 ligand (h-CD40L) alone or with h-CD40L and human B cell activating factor (h-BAFF). They were subsequently co-cultured with the corresponding irradiated stimulator PBMCs, and all cells were administered into naïve NSG mice. Although all three humanized models had sufficient human total-IgG and anti-HLA antibody production, allospecific anti-HLA Ab production was prominently suppressed whereas non-specific anti-HLA Abs were sufficiently detected. Therefore, this novel humanized mouse model might be useful for analyzing the mechanism of anti-allogeneic human B cell tolerance induction.

BSHI guideline: HLA matching and donor selection for haematopoietic progenitor cell transplantation.

A review of the British Society for Histocompatibility and Immunogenetics (BSHI) Guideline 'HLA matching and donor selection for haematopoietic progenitor cell transplantation' published in 2016 was undertaken by a BSHI appointed writing committee. Literature searches were performed and the data extracted were presented as recommendations according to the GRADE nomenclature.

HLA in Alzheimer's Disease: Genetic Association and Possible Pathogenic Roles.

Alzheimer's disease (AD) is commonly considered as the most prominent dementing disorder globally and is characterized by the deposition of misfolded amyloid-ß (Aß) peptide and the aggregation of neurofibrillary tangles. Immunological disturbances and neuroinflammation, which result from abnormal immunological reactivations, are believed to be the primary stimulating factors triggering AD-like neuropathy. It has been suggested by multiple previous studies that a bunch of AD key influencing factors might be attributed to genes encoding human leukocyte antigen (HLA), whose variety is an essential part of human adaptive immunity. A wide range of activities involved in immune responses may be determined by HLA genes, including inflammation mediated by the immune response, T-cell transendothelial migration, infection, brain development and plasticity in AD pathogenesis, and so on. The goal of this article is to review the recent epidemiological findings of HLA (mainly HLA class I and II) associated with AD and investigate to what extent the genetic variations of HLA were clinically significant as pathogenic factors for AD. Depending on the degree of contribution of HLA in AD pathogenesis, targeted research towards HLA may propel AD therapeutic strategies into a new era of development.

Predictive factors and early biomarkers of response in multiple sclerosis patients treated with natalizumab.

There are an increasing number of treatments available for multiple sclerosis (MS). The early identification of optimal responders to individual treatments is important to achieve individualized therapy. With this aim, we performed a multicenter retrospective longitudinal study including 186 MS patients treated with natalizumab who were followed for 2 years. We analyzed the following variables at recruitment: sex, current age, age at disease onset, disease duration, EDSS, number of T2 and Gd + lesions, IgG and IgM oligoclonal bands, HLA class II (DR, DRB, DQA, DQB, and DRB1*15:01), IgG and IgM antibody titers against human herpesvirus 6 (HHV-6) and the antibody response to Epstein-Barr virus (EBV) through the measurement of the anti-EBNA-1 and anti-VCA IgG titers, in relation to clinical response (no relapses or disability progression), and to NEDA-3 (no evidence of disease activity in terms of clinical response and no changes in MRI scans either) after 2-years follow-up. Baseline EDSS score, baseline EBNA-1 IgG titers and percentage change of HHV6 IgG titers between baseline and 6 month visits were significantly different in clinical responders and in NEDA-3 status (all of them remained significant in the multivariate analysis). We identified three variables for the early identification of natalizumab optimal responders in a rapid and cost-effective approach.

A familial case of Kikuchi-Fujimoto disease in dizygotic twins.

BACKGROUND: Kikuchi-Fujimoto disease (KFD) or necrotizing histiocytic lymphadenitis, was described separately by both Kikuchi and Fujimoto in Japan in the early 1970's. Despite its rarity in the pediatric population, it is an important differential in persistent lymphadenopathy. Familial cases of KFD in the literature are rare. Here we describe the first reported case of KFD in non-identical twin sisters. CASE PRESENTATION: Twin 1 presented with a 3-week history of worsening right-sided cervical lymphadenopathy, daily fevers, significant lethargy, weight loss and arthralgia of her knees and ankles at the age of 12 years in 2015. She had had an unremarkable medical history. A biopsy of her lymph nodes showed histiocytic necrosis consistent with KFD. Twin 2 presented with a three-week history of lethargy, fatigue, weight loss and left-sided posterior cervical chain lymphadenopathy at 16 years of age in 2018. She had a history of frequently relapsing nephrotic syndrome and celiac disease. A biopsy of her lymph nodes was undertaken and showed histiocytic necrosis consistent with KFD. CONCLUSIONS: KFD is a rare but self-limiting pathological process of necrotizing histiocytic lymphadenitis. Although further research is needed, there is an increasing amount of evidence which suggests a multifactorial pathological basis of disease. The two cases we document here are the first reported cases of familial KFD in dizygotic HLA-identical twins which reinforces the likely HLA-linkage in the etiology of KFD.

Activity of the human immortalized endothelial progenitor cell line HEPC-CB.1 supporting in vitro angiogenesis.

The human HEPC-CB.1 cell line with many characteristics of endothelial progenitor cells (EPC) was tested for its proangiogenic properties as a potentially therapeutic compound. HEPC-CB.1 cells' potential to differentiate into endothelial cells was revealed after treating the cells with a mixture of ATRA, cAMP and VEGF, as shown by the reduced expression levels of CD133, CD271 and CD90 antigens, augmentation of CD146 and CD31, and a decrease in cell clonogenicity. The cooperation of HEPC-CB.1 with the endothelial cell line HSkMEC.2 resulted in the formation of a common network. Tube formation was significantly more effective when resulting from HEPC-CB.1 and HSkMEC.2 cell co-culture as compared to a monoculture of each cell line. The exocrine mechanism of HEPC-CB.1 and HSkMEC.2 cross talk by secreted factors was evidenced using the HEPC-CB.1 supernatant to increase the efficacy of HSkMEC.2 tube formation. The proangiogenic factors produced by HEPC-CB.1 were identified using cytokine antibody array. Out of 120 examined factors, the HEPC-CB.1 cell line produced 63, some with known angiogenic activity. As in vivo the angiogenic process occurs at low oxygen tension, it was observed that in hypoxia, the production of defined factors was augmented. The presented results demonstrate that HEPC-CB.1 cells are able to both cooperate and integrate in a newly formed network and produce factors that help the network formation. The results suggest that HEPC-CB.1 cells are indeed endothelial progenitors and may prove to be an effective tool in regenerative medicine.

5-year follow-up of spinal and sacroiliac MRI abnormalities in early axial spondyloarthritis: data from the DESIR cohort.

OBJECTIVE: To study changes on MRI of the spine and sacroiliac joint (SIJ) in early axial spondyloarthritis (axSpA) over time. METHODS: In the Devenir des Spondyloarthropathies Indifférenciées Récentes cohort, MRI-spine and MRI-SIJ at baseline and 2 and 5 years were scored by central readers for bone marrow oedema (BME), fatty lesions, erosions, sclerosis, ankylosis and spinal bone spurs. The average mean number of lesions was reported or the agreement of ≥2 out of 3 readers for binary outcomes. Net progression was calculated by subtracting the patients that 'improved' from those that 'worsened' divided by the total number of patients. RESULTS: Over 5 years, in 155 patients with axSpA (mean age 33.5 (SD 8.9) years, symptom duration 1.4 (0.8) years, 63% human leucocyte antigen+, 14% modified New York+), BME on MRI-SIJ decreased by a mean Spondyloarthritis Research Consortium of Canada score of 1.4 (SD 6.5) (p=0.009). The largest BME decrease was observed in patients using biological disease-modifying antirheumatic drugs at 5 years. Spinal BME increased by 0.3 (4.6) (p=0.41). Fatty lesions and/or erosions on MRI-SIJ increased by a mean of 1.0 (SD 2.6) (p<0.001). Spinal fatty lesions and/or erosions increased by 0.2 (SD 0.5) (p<0.001). Compared with baseline, at 5 years, 7.3% less patients had BME on MRI-SIJ according to the Assessment of Spondyloarthritis International Society definition, while 6.6% more patients had ≥5 fatty lesions and/or erosions. At 5 years, 0.7% less patients had ≥5 spinal BME lesions and 0.7% less patients had ≥5 spinal fatty lesions. CONCLUSION: Over 5 years, BME on MRI-SIJ decreased and spinal BME remained similar, but numerically, little progression of structural lesions on MRI of the SIJ and spine was seen.

Association of HLA Typing and Alloimmunity With Posttransplantation Membranous Nephropathy: A Multicenter Case Series.

RATIONALE & OBJECTIVES: Posttransplantation membranous nephropathy (MN) represents a rare complication of kidney transplantation that can be classified as recurrent or de novo. The clinical, pathologic, and immunogenetic characteristics of posttransplantation MN and the differences between de novo and recurrent MN are not well understood. STUDY DESIGN: Multicenter case series. SETTING & PARTICIPANTS: We included 77 patients from 5 North American and European medical centers with post-kidney transplantation MN (27 de novo and 50 recurrent). Patients with MN in the native kidney who received kidney allografts but did not develop recurrent MN were used as nonrecurrent controls (n = 43). To improve understanding of posttransplantation MN, we compared de novo MN with recurrent MN and then contrasted recurrent MN with nonrecurrent controls. FINDINGS: Compared with recurrent MN, de novo MN was less likely to be classified as primary MN (OR, 0.04; P < 0.001) and had more concurrent antibody-mediated rejection (OR, 12.0; P < 0.001) and inferior allograft survival (HR for allograft failure, 3.2; P = 0.007). HLA-DQ2 and HLA-DR17 antigens were more common in recipients with recurrent MN compared with those with de novo MN; however, the frequency of these recipient antigens in recurrent MN was similar to that in nonrecurrent MN controls. Among the 93 kidney transplant recipients with native kidney failure attributed to MN, older recipient age (HR per each year older, 1.03; P = 0.02), recipient HLA-A3 antigen (HR, 2.5; P = 0.003), steroid-free immunosuppressive regimens (HR, 2.84; P < 0.001), and living related allograft (HR, 1.94; P = 0.03) were predictors of MN recurrence. LIMITATIONS: Retrospective case series, limited sample size due to rarity of the disease, nonstandardized nature of data collection and biopsies. CONCLUSIONS: De novo and recurrent MN likely represent separate diseases. De novo MN is associated with humoral alloimmunity and guarded outcome. Potential predisposing factors for recurrent MN include recipients who are older, recipient HLA-A3 antigen, steroid-free immunosuppressive regimen, and living related donor kidney.

A case of hepatosplenic T-cell lymphoma successfully treated by HLA haploidentical stem cell transplantation.

We report a case of hepatosplenic T-cell lymphoma (HSTL) transplanted from an HLA-haploidentical daughter. A 51-year-old man was referred due to liver function test abnormalities and fever. He was confirmed to have γδ-type HSTL by bone marrow and liver biopsies. He was treated with five cycles of a CHOP regimen. Although metabolic complete response (CR), as defined by positron emission tomography, was achieved, his bone marrow still contained tumor cells on polymerase chain reaction (PCR). He underwent transplantation using unmanipulated peripheral blood stem cells from his HLA-haploidentical daughter. The preconditioning regimen consisted of fludarabine, melphalan, busulfan and antithymocyte globulin. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus and short-term methotrexate. Neutrophil engraftment was achieved on day 14. His bone marrow exhibited a completely female phenotype by fluorescence in situ hybridization, and no lymphoma cells were detected by PCR on day 30. Although he developed grade II acute GVHD on day 47, it was successfully treated by prednisolone. He has a limited type of skin chronic GVHD and still receives oral immunosuppressive therapy. He remains in CR four years after transplantation.

Human Leukocyte Antigen alleles associated with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

The etiology and pathogenesis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) are unknown, and autoimmunity is one of many proposed underlying mechanisms. Human Leukocyte Antigen (HLA) associations are hallmarks of autoimmune disease, and have not been thoroughly investigated in a large ME/CFS patient cohort. We performed high resolution HLA -A, -B, -C, -DRB1, -DQB1 and -DPB1 genotyping by next generation sequencing in 426 adult, Norwegian ME/CFS patients, diagnosed according to the Canadian Consensus Criteria. HLA associations were assessed by comparing to 4511 healthy and ethnically matched controls. Clinical information was collected through questionnaires completed by patients or relatives. We discovered two independent HLA associations, tagged by the alleles HLA-C*07:04 (OR 2.1 [95% CI 1.4-3.1]) and HLA-DQB1*03:03 (OR 1.5 [95% CI 1.1-2.0]). These alleles were carried by 7.7% and 12.7% of ME/CFS patients, respectively. The proportion of individuals carrying one or both of these alleles was 19.2% in the patient group and 12.2% in the control group (OR 1.7 [95% CI 1.3-2.2], pnc = 0.00003). ME/CFS is a complex disease, potentially with a substantial heterogeneity. We report novel HLA associations pointing toward the involvement of the immune system in ME/CFS pathogenesis.

Association between radiotherapy-induced alteration of programmed death ligand 1 and survival in patients with uterine cervical cancer undergoing preoperative radiotherapy.

PURPOSE: To evaluate radiotherapy-induced changes in the expression of programmed death ligand 1 (PD-L1), programmed death 1 (PD-1), and human leukocyte antigen class I (HLA-1) in patients with uterine cervical cancer, as well as infiltration of CD8+ and Forkhead box P3+ (FoxP3+) T lymphocytes into tumor tissue and the prognostic value of these parameters. MATERIALS AND METHODS: We performed immunohistochemical analysis of pre-radiotherapy biopsies and corresponding post-radiotherapy resected tissues in 104 uterine cervical cancer patients undergoing preoperative chemoradiotherapy or radiotherapy alone. We scored the expression of various proteins to distinguish positive from negative samples. RESULTS: PD-L1-expressing tumor cells (PD-L1 TC) increased significantly after chemoradiotherapy (p = 0.043). CD8+ T cell infiltration (p = 0.002) and FoxP3+ T cell infiltration (p = 0.003) decreased significantly after chemoradiotherapy. Expression of PD­1, PD-L1-expressing immune cells (PD-L1 IC), and HLA­1 did not change after chemoradiotherapy. In biopsy specimens obtained before chemoradiotherapy or radiotherapy, greater infiltration of CD8+ T cells (p = 0.001) and FoxP3+ T cells (p = 0.003) were significant predictors of better overall survival (OS). In surgical specimens obtained after chemoradiotherapy or radiotherapy, greater infiltration of PD-L1 TC was the only significant predictor of better OS (p < 0.001) and was related to a significantly lower probability of out-of-field recurrence (p = 0.005). CONCLUSION: Chemoradiotherapy induced an immunologic shift that increased PD-L1 TC. Chemoradiotherapy has immunological effects that can influence the results of treatment for uterine cervical cancer.

Posttransplant Outcomes for cPRA-100% Recipients Under the New Kidney Allocation System.

BACKGROUND: There is concern in the transplant community that outcomes for the most highly sensitized recipients might be poor under Kidney Allocation System (KAS) high prioritization. METHODS: To study this, we compared posttransplant outcomes of 525 pre-KAS (December 4, 2009, to December 3, 2014) calculated panel-reactive antibodies (cPRA)-100% recipients to 3026 post-KAS (December 4, 2014, to December 3, 2017) cPRA-100% recipients using SRTR data. We compared mortality and death-censored graft survival using Cox regression, acute rejection, and delayed graft function (DGF) using logistic regression, and length of stay (LOS) using negative binomial regression. RESULTS: Compared with pre-KAS recipients, post-KAS recipients were allocated kidneys with lower Kidney Donor Profile Index (median 30% versus 35%, P < 0.001) but longer cold ischemic time (CIT) (median 21.0 h versus 18.6 h, P < 0.001). Compared with pre-KAS cPRA-100% recipients, those post-KAS had higher 3-year patient survival (93.6% versus 91.4%, P = 0.04) and 3-year death-censored graft survival (93.7% versus 90.6%, P = 0.005). The incidence of DGF (29.3% versus 29.2%, P = 0.9), acute rejection (11.2% versus 11.7%, P = 0.8), and median LOS (5 d versus 5d, P = 0.2) were similar between pre-KAS and post-KAS recipients. After accounting for secular trends and adjusting for recipient characteristics, post-KAS recipients had no difference in mortality (adjusted hazard ratio [aHR]: 0.861.623.06, P = 0.1), death-censored graft failure (aHR: 0.521.001.91, P > 0.9), DGF (adjusted odds ratio [aOR]: 0.580.861.27, P = 0.4), acute rejection (aOR: 0.610.941.43, P = 0.8), and LOS (adjusted LOS ratio: 0.981.161.36, P = 0.08). CONCLUSIONS: We did not find any statistically significant worsening of outcomes for cPRA-100% recipients under KAS, although longer-term monitoring of posttransplant mortality is warranted.

Uncovering Thousands of New Peptides with Sequence-Mask-Search Hybrid De Novo Peptide Sequencing Framework.

Typical analyses of mass spectrometry data only identify amino acid sequences that exist in reference databases. This restricts the possibility of discovering new peptides such as those that contain uncharacterized mutations or originate from unexpected processing of RNAs and proteins. De novo peptide sequencing approaches address this limitation but often suffer from low accuracy and require extensive validation by experts. Here, we develop SMSNet, a deep learning-based de novo peptide sequencing framework that achieves >95% amino acid accuracy while retaining good identification coverage. Applications of SMSNet on landmark proteomics and peptidomics studies reveal over 10,000 previously uncharacterized HLA antigens and phosphopeptides, and in conjunction with database-search methods, expand the coverage of peptide identification by almost 30%. The power to accurately identify new peptides of SMSNet would make it an invaluable tool for any future proteomics and peptidomics studies, including tumor neoantigen discovery, antibody sequencing, and proteome characterization of non-model organisms.