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SummaryBackgroundTissue transglutaminase (tTG) immunoglobulin A (IgA) testing is a sensitive adjunct to the diagnosis of coeliac disease. The threshold for positivity was developed for diagnosis, with negative results reported as below the reference value (<4 U/mL).AimTo investigate if an undetectable (tTG IgA<1.2 U/mL) is more predictive of healing compared to patients with negative but detectable serology (1.2‐3.9 U/mL).MethodsWe performed a retrospective study of 402 treated coeliac disease patients seen at the Mayo Clinic with negative tTG IgA values drawn within 1 month of duodenal biopsy between January 2009 and December 2015. The Corazza‐Villanacci score was used to assess mucosal healing. The presence of gastrointestinal symptoms was also collected. Logistic regression was used to assess the relationship of clinical variables with a normal biopsy.ResultsPatients with undetectable titres more frequently had normal duodenal histology compared to patients with detectable tTG IgA levels (117/240 vs. 53/162; OR=1.96; 1.292, 2.961). Asymptomatic patients more frequently had normal duodenum as compared to symptomatic patients (88/163 vs. 82/239; OR=2.25; CI: 1.494, 3.377). Patients with undetectable serology and on a gluten‐free diet for ≥2 years were more likely to have no villous atrophy compared to patients with detectable serology (148/192 vs. 55/88; OR=2.02; CI: 1.17, 3.49).ConclusionIn subjects recovering from coeliac disease with negative tTG IgA serology, an undetectable titre is associated with normal histology on follow‐up biopsy.

Assessment of tumor-infiltrating lymphocytes (TILs) in histopathologic specimens can provide important prognostic information in diverse solid tumor types, and may also be of value in predicting response to treatments. However, implementation as a routine clinical biomarker has not yet been achieved. As successful use of immune checkpoint inhibitors and other forms of immunotherapy become a clinical reality, the need for widely applicable, accessible, and reliable immunooncology biomarkers is clear. In part 1 of this review we briefly discuss the host immune response to tumors and different approaches to TIL assessment. We propose a standardized methodology to assess TILs in solid tumors on hematoxylin and eosin sections, in both primary and metastatic settings, based on the International Immuno-Oncology Biomarker Working Group guidelines for TIL assessment in invasive breast carcinoma. A review of the literature regarding the value of TIL assessment in different solid tumor types follows in part 2. The method we propose is reproducible, affordable, easily applied, and has demonstrated prognostic and predictive significance in invasive breast carcinoma. This standardized methodology may be used as a reference against which other methods are compared, and should be evaluated for clinical validity and utility. Standardization of TIL assessment will help to improve consistency and reproducibility in this field, enrich both the quality and quantity of comparable evidence, and help to thoroughly evaluate the utility of TILs assessment in this era of immunotherapy.

Assessment of the immune response to tumors is growing in importance as the prognostic implications of this response are increasingly recognized, and as immunotherapies are evaluated and implemented in different tumor types. However, many different approaches can be used to assess and describe the immune response, which limits efforts at implementation as a routine clinical biomarker. In part 1 of this review, we have proposed a standardized methodology to assess tumor-infiltrating lymphocytes (TILs) in solid tumors, based on the International Immuno-Oncology Biomarkers Working Group guidelines for invasive breast carcinoma. In part 2 of this review, we discuss the available evidence for the prognostic and predictive value of TILs in common solid tumors, including carcinomas of the lung, gastrointestinal tract, genitourinary system, gynecologic system, and head and neck, as well as primary brain tumors, mesothelioma and melanoma. The particularities and different emphases in TIL assessment in different tumor types are discussed. The standardized methodology we propose can be adapted to different tumor types and may be used as a standard against which other approaches can be compared. Standardization of TIL assessment will help clinicians, researchers and pathologists to conclusively evaluate the utility of this simple biomarker in the current era of immunotherapy.

AbstractObjectiveHLA‐DPB1 matching may impact allogeneic hematopoietic stem cell transplantation (ASCT) outcomes; however, this locus is not in linkage disequilibrium with the remainder of the HLA genes. After classifying HLA‐DPB1 mismatches based on T‐cell epitope, avoiding non‐permissive mismatches may impact survival. We tested this hypothesis at a single academic institution.MethodsRetrospective HLA‐DPB1 genotyping was performed on 153 adult patients who underwent ASCT and unrelated donors matched for HLA‐A, B, C, DRB1, and DQB1 loci (10/10). Using the ImMunoGeneTics/HLA T‐cell epitope matching algorithm, mismatch status was classified as permissive or non‐permissive.ResultsOf 153 donor‐recipient pairs, 22 (14.4%) were HLA‐DPB1 matches, 64 (42.8%) permissive mismatches, and 67 (43.8%) non‐permissive mismatches. DPB1 mismatch increased risk of chronic graft‐versus‐host disease (cGVHD; RR 2.89 [1.19‐9.53], P=.016) compared with DPB1‐matched transplants, but there were no differences in overall mortality, risk of relapse, or acute GVHD (aGVHD). Combining matches and permissive mismatches and comparing to non‐permissive mismatches, there was no significant difference in overall survival or relapse; however, patients receiving non‐permissive mismatched transplants experienced greater risk of aGVHD overall and severe aGVHD (RR 1.66 [1.13‐2.44], P=.010 and RR 1.97 [1.10‐3.59], P=.024, respectively).ConclusionIn this single‐center study, HLA‐DPB1 matching influenced outcomes of patients undergoing ASCT for hematologic malignancy.

Context.— Numerous feasibility studies to type human leukocyte antigens (HLAs) by next-generation sequencing (NGS) have led to the development of vendor-supported kits for HLA typing by NGS. Some clinical laboratories have introduced HLA-NGS, and many are investigating the introduction. Standards from accrediting agencies form the regulatory framework for introducing this test into clinical laboratories. Objectives.— To provide an assessment of metrics and considerations relevant to the successful implementation of clinical HLA-NGS typing, and to provide as a reference a validated HLA-NGS protocol used clinically since December 2013 at the Children's Hospital of Philadelphia (Philadelphia, Pennsylvania). Data Sources.— The HLA-NGS has been performed on 2532 samples. The initial 1046 and all homozygous samples were also typed by an alternate method. The HLA-NGS demonstrated 99.7% concordance with the alternate method. Ambiguous results were most common at the DPB1 locus because of a lack of phasing between exons 2 and 3 or the unsequenced exon 1 (533 of 2954 alleles; 18.04%) and the DRB1 locus because of not sequencing exon 1 (75 of 3972 alleles; 1.89%). No ambiguities were detected among the other loci. Except for 2 false homozygous samples, all homozygous samples (1891) demonstrated concordance with the alternate method. The article is organized to address the critical elements in the preanalytic, analytic, and postanalytic phases of introducing this assay into the clinical laboratory. Conclusions.— The results demonstrate that HLA typing by NGS is a highly accurate, reproducible, efficient method that provides more-complete sequencing information for the length of the HLA gene and can be the single methodology for HLA typing in clinical immunogenetics laboratories.

AbstractThe Fenwal Alyx for collecting double red cell products has two red cell volume collection settings: fixed collection target of 360 ml (180 ml/unit) and a variable target of collecting either 400 or 360 ml (200 or 180 ml/unit), where the machine aims for the higher possible collection target. We retrospectively compared the two collection targets for the RBC content, donor time, technician time, and collection efficiency. We compared 18 fixed (F) target collections to 40 variable (V) target collections. All collections were performed as per the manufacturer's recommendations on Alyx and donors met the manufacturer's eligibility criteria. There was no significant difference in average whole blood processed (F: 963 ml, V: 1,000 ml); donor time (F: 43 min, V: 45 min) or technician time (F: 64 min, V: 64 min). There was a significant difference in unit volume (F: 283 ml, V: 300 ml); grams Hb/unit (F: 53 g, V: 57 g); ml RBC/unit (F: 157 ml, V: 167 ml); and RBC recovery (F: 87.8%, V: 88.9%). The fixed target had a significantly lower frequency of products with ≥51 g Hb (80.6%) than variable target (96.3%) and ≥153 ml RBC/unit (F: 55.6%, V: 96.3%). In conclusion, the variable target efficiently allows collections of products with higher red cell volume and hemoglobin without a significant increase in collection and processing time.

BACKGROUNDWe compared three instruments for double red blood cell (DRBC) collection to efficiently optimize our RBC inventory.STUDY DESIGN AND METHODSInstruments compared were the TerumoBCT Trima Accel (Trima), the Fenwal Alyx (Alyx), and the Haemonetics MCS+ 8150 (MCS+). Forty consecutive collections (80 products) per instrument were evaluated for hemoglobin (Hb) content, leukoreduction, collection time, instrument efficiency, donor acceptance, and reactions. The total number of whole blood donors who could be eligible for DRBC collection was analyzed. All collections were as per the manufacturer recommendations with target volume of 360 or 400mL. Leukoreduction was integral to the collection procedure for the Alyx and Trima, while it was a separate process for the MCS+.RESULTSThe total numbers of whole blood donors who could be eligible for DRBC collection were 10,116 for the MCS+, 9378 for the Alyx, and 8573 for the Trima. All units collected had more than 42.5 g of Hb. Mean Hb levels were as follows: Trima, 59.2 g; Alyx, 56.8 g; and MCS+, 51.5 g. Donor times for the Trima, Alyx, and MCS+ were 52, 45, and 52 minutes, respectively. Technician times for the Trima, Alyx, and MCS+ (without filtration) were 87, 73, and 64 minutes. All collected products had fewer than 5 × 106 white blood cells.CONCLUSIONSAll three instruments would be capable of collecting an acceptable leukoreduced DRBC product. The Alyx was most portable, with the shortest donor time and total technician time (considering filtration time) and highest collection efficiency and would collect from more donors than the Trima. We thus chose the Alyx as it best fits the specific needs of our center.