Germline homozygosity and allelic imbalance of HLA-I are common in esophagogastric adenocarcinoma and impair the repertoire of immunogenic peptides

BACKGROUND

The individual HLA-I genotype is associated with cancer, autoimmune diseases and infections. This study elucidates the role of germline homozygosity or allelic imbalance of HLA-I loci in esophago-gastric adenocarcinoma (EGA) and determines the resulting repertoires of potentially immunogenic peptides.

METHODS

HLA genotypes and sequences of either (1) 10 relevant tumor-associated antigens (TAAs) or (2) patient-specific mutation-associated neoantigens (MANAs) were used to predict good-affinity binders using an in silico approach for MHC-binding (www.iedb.org). Imbalanced or lost expression of HLA-I-A/B/C alleles was analyzed by transcriptome sequencing. FluoroSpot assays and TCR sequencing were used to determine peptide-specific T-cell responses.

RESULTS

We show that germline homozygosity of HLA-I genes is significantly enriched in EGA patients (n=80) compared with an HLA-matched reference cohort (n=7605). Whereas the overall mutational burden is similar, the repertoire of potentially immunogenic peptides derived from TAAs and MANAs was lower in homozygous patients. Promiscuity of peptides binding to different HLA-I molecules was low for most TAAs and MANAs and in silico modeling of the homozygous to a heterozygous HLA genotype revealed normalized peptide repertoires. Transcriptome sequencing showed imbalanced expression of HLA-I alleles in 75% of heterozygous patients. Out of these, 33% showed complete loss of heterozygosity, whereas 66% had altered expression of only one or two HLA-I molecules. In a FluoroSpot assay, we determined that peptide-specific T-cell responses against NY-ESO-1 are derived from multiple peptides, which often exclusively bind only one HLA-I allele.

CONCLUSION

The high frequency of germline homozygosity in EGA patients suggests reduced cancer immunosurveillance leading to an increased cancer risk. Therapeutic targeting of allelic imbalance of HLA-I molecules should be considered in EGA.

Oncogenic role and target properties of the lysine-specific demethylase KDM1A in chronic lymphocytic leukemia

In chronic lymphocytic leukemia (CLL), epigenetic alterations are considered to centrally shape the transcriptional signatures that drive disease evolution and underlie its biological and clinical subsets. Characterizations of epigenetic regulators, particularly histone-modifying enzymes, are very rudimentary in CLL. In efforts to establish effectors of the CLL-associated oncogene T-cell leukemia 1A (TCL1A), we identified here the lysine-specific histone demethylase KDM1A to interact with the TCL1A protein in B cells in conjunction with an increased catalytic activity of KDM1A. We demonstrate that KDM1A is upregulated in malignant B cells. Elevated KDM1A and associated gene expression signatures correlated with aggressive disease features and adverse clinical outcomes in a large prospective CLL trial cohort. Genetic Kdm1a knockdown in Eμ-TCL1A mice reduced leukemic burden and prolonged animal survival, accompanied by upregulated p53 and proapoptotic pathways. Genetic KDM1A depletion also affected milieu components (T, stromal, and monocytic cells), resulting in significant reductions in their capacity to support CLL-cell survival and proliferation. Integrated analyses of differential global transcriptomes (RNA sequencing) and H3K4me3 marks (chromatin immunoprecipitation sequencing) in Eμ-TCL1A vs iKdm1aKD;Eμ-TCL1A mice (confirmed in human CLL) implicate KDM1A as an oncogenic transcriptional repressor in CLL which alters histone methylation patterns with pronounced effects on defined cell death and motility pathways. Finally, pharmacologic KDM1A inhibition altered H3K4/9 target methylation and revealed marked anti-B-cell leukemic synergisms. Overall, we established the pathogenic role and effector networks of KDM1A in CLL via tumor-cell intrinsic mechanisms and its impacts in cells of the microenvironment. Our data also provide rationales to further investigate therapeutic KDM1A targeting in CLL.

Immune responses against shared antigens are common in esophago-gastric cancer and can be enhanced using CD40-activated B cells

BACKGROUND

Specific immune response is a hallmark of cancer immunotherapy and shared tumor-associated antigens (TAAs) are important targets. Recent advances using combined cellular therapy against multiple TAAs renewed the interest in this class of antigens. Our study aims to determine the role of TAAs in esophago-gastric adenocarcinoma (EGA).

METHODS

RNA expression was assessed by NanoString in tumor samples of 41 treatment-naïve EGA patients. Endogenous T cell and antibody responses against the 10 most relevant TAAs were determined by FluoroSpot and protein-bound bead assays. Digital image analysis was used to evaluate the correlation of TAAs and T-cell abundance. T-cell receptor sequencing, in vitro expansion with autologous CD40-activated B cells (CD40Bs) and in vitro cytotoxicity assays were applied to determine specific expansion, clonality and cytotoxic activity of expanded T cells.

RESULTS

68.3% of patients expressed ≥5 TAAs simultaneously with coregulated clusters, which were similar to data from The Cancer Genome Atlas (n=505). Endogenous cellular or humoral responses against ≥1 TAA were detectable in 75.0% and 53.7% of patients, respectively. We found a correlation of T-cell abundance and the expression of TAAs and genes related to antigen presentation. TAA-specific T-cell responses were polyclonal, could be induced or enhanced using autologous CD40Bs and were cytotoxic in vitro. Despite the frequent expression of TAAs co-occurrence with immune responses was rare.

CONCLUSIONS

We identified the most relevant TAAs in EGA for monitoring of clinical trials and as therapeutic targets. Antigen-escape rather than missing immune response should be considered as mechanism underlying immunotherapy resistance of EGA.

Microvascular perfusion, perfused boundary region and glycocalyx shedding in patients with autosomal dominant polycystic kidney disease: results from the GlycoScore III study

Background

Vascular abnormalities and endothelial dysfunction are part of the spectrum of autosomal dominant polycystic kidney disease (ADPKD). The mechanisms behind these manifestations, including potential effects on the endothelial surface layer (ESL) and glycocalyx integrity, remain unknown.

Methods

Forty-five ambulatory adult patients with ADPKD were enrolled in this prospective, observational, cross-sectional, single-centre study. Fifty-one healthy volunteers served as a control group. All participants underwent real-time microvascular perfusion measurements of the sublingual microcirculation using sidestream dark field imaging. After image acquisition, the perfused boundary region (PBR), an inverse parameter for red blood cell (RBC) penetration into the ESL, was automatically calculated. Microvascular perfusion was assessed by RBC filling and capillary density. Concentrations of circulating glycocalyx components were determined by enzyme-linked immunosorbent assay.

Results

ADPKD patients showed a significantly larger PBR compared with healthy controls (2.09 ± 0.23 µm versus 1.79 ± 0.25 µm; P < .001). This was accompanied by significantly lower RBC filling (70.4 ± 5.0% versus 77.9 ± 5.4%; P < .001) as well as a higher valid capillary density {318/mm² [interquartile range (IQR) 269-380] versus 273/mm² [230-327]; P = .007}. Significantly higher plasma concentrations of heparan sulphate (1625 ± 807 ng/ml versus 1329 ± 316 ng/ml; P = .034), hyaluronan (111 ng/ml [IQR 79-132] versus 92 ng/ml [82-98]; P = .042) and syndecan-1 were noted in ADPKD patients compared with healthy controls (35 ng/ml [IQR 27-57] versus 29 ng/ml [23-42]; P = .035).

Conclusions

Dimensions and integrity of the ESL are impaired in ADPKD patients. Increased capillary density may be a compensatory mechanism for vascular dysfunction to ensure sufficient tissue perfusion and oxygenation.

Tripartite antigen-agnostic combination immunotherapy cures established poorly immunogenic tumors

Background

Single-agent immunotherapy has shown remarkable efficacy in selected cancer entities and individual patients. However, most patients fail to respond. This is likely due to diverse immunosuppressive mechanisms acting in a concerted way to suppress the host anti-tumor immune response. Combination immunotherapy approaches that are effective in such poorly immunogenic tumors mostly rely on precise knowledge of antigenic determinants on tumor cells. Creating an antigen-agnostic combination immunotherapy that is effective in poorly immunogenic tumors for which an antigenic determinant is not known is a major challenge.

Methods

We use multiple cell line and poorly immunogenic syngeneic, autochthonous, and autologous mouse models to evaluate the efficacy of a novel combination immunotherapy named tripartite immunotherapy (TRI-IT). To elucidate TRI-ITs mechanism of action we use immune cell depletions and comprehensive tumor and immune infiltrate characterization by flow cytometry, RNA sequencing and diverse functional assays.

Results

We show that combined adoptive cellular therapy (ACT) with lymphokine-activated killer cells, cytokine-induced killer cells, Vγ9Vδ2-T-cells (γδ-T-cells) and T-cells enriched for tumor recognition (CTLs) display synergistic antitumor effects, which are further enhanced by cotreatment with anti-PD1 antibodies. Most strikingly, the full TRI-IT protocol, a combination of this ACT with anti-PD1 antibodies, local immunotherapy of agonists against toll-like receptor 3, 7 and 9 and pre-ACT lymphodepletion, eradicates and induces durable anti-tumor immunity in a variety of poorly immunogenic syngeneic, autochthonous, as well as autologous humanized patient-derived models. Mechanistically, we show that TRI-IT coactivates adaptive cellular and humoral, as well as innate antitumor immune responses to mediate its antitumor effect without inducing off-target toxicity.

Conclusions

Overall, TRI-IT is a novel, highly effective, antigen-agnostic, non-toxic combination immunotherapy. In this study, comprehensive insights into its preclinical efficacy, even in poorly immunogenic tumors, and mode of action are given, so that translation into clinical trials is the next step.

No substantial preexisting B cell immunity against SARS-CoV-2 in healthy adults

Preexisting immunity against SARS-CoV-2 may have critical implications for our understanding of COVID-19 susceptibility and severity. The presence and clinical relevance of a preexisting B cell immunity remain to be fully elucidated. Here, we provide a detailed analysis of the B cell immunity to SARS-CoV-2 in unexposed individuals. To this end, we extensively investigated SARS-CoV-2 humoral immunity in 150 adults sampled pre-pandemically. Comprehensive screening of donor plasma and purified IgG samples for binding and neutralization in various functional assays revealed no substantial activity against SARS-CoV-2 but broad reactivity to endemic betacoronaviruses. Moreover, we analyzed antibody sequences of 8,174 putatively SARS-CoV-2-reactive B cells at a single cell level and generated and tested 158 monoclonal antibodies. None of these antibodies displayed relevant binding or neutralizing activity against SARS-CoV-2. Taken together, our results show no evidence of competent preexisting antibody and B cell immunity against SARS-CoV-2 in unexposed adults.

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Comprehensive analysis of the B cell response to SARS-CoV-2 in pre-pandemic samples

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No substantial plasma and IgG reactivity against SARS-CoV-2

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MAbs isolated from pre-pandemic samples showed no SARS-CoV-2 neutralizing activity

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No indication of competent preexisting B cell immunity against SARS-CoV-2

Non-canonical function of AGO2 augments T-cell receptor signaling in T-cell prolymphocytic leukemia

T-cell prolymphocytic leukemia (T-PLL) is a chemotherapy-refractory T-cell malignancy with limited therapeutic options and a poor prognosis. Current disease concepts implicate TCL1A oncogene-mediated enhanced T-cell receptor (TCR) signaling and aberrant DNA repair as central perturbed pathways. We discovered that recurrent gains on chromosome 8q more frequently involve the AGO2 gene than the adjacent MYC locus as the affected minimally amplified genomic region. AGO2 has been understood as a pro-tumorigenic key regulator of microRNA (miR) processing. In primary tumor material and cell line models, AGO2 overrepresentation associated (i) with higher disease burden, (ii) with enhanced in vitro viability and growth of leukemic T-cells, and (iii) with miR-omes and transcriptomes that highlight altered survival signaling, abrogated cell cycle control, and defective DNA damage responses. Moreover, AGO2 elicited immediate, rather than non-RNA mediated, effects in leukemic T-cells. Systems of genetically modulated AGO2 revealed that it enhances TCR signaling, particularly at the level of ZAP70, PLCγ1, and LAT kinase phospho-activation. In global mass-spectrometric analyses, AGO2 interacted with a unique set of partners in a TCR-stimulated context, including the TCR kinases LCK and ZAP70, forming membranous protein complexes. Models of their three-dimensional structure also suggested that AGO2 undergoes post-transcriptional modi-fications by LCK. This novel TCR-associated non-canonical function of AGO2 represents, in addition to TCL1A-mediated TCR signal augmentation, another enhancer mechanism of this important deregulated growth pathway in T-PLL. These findings further emphasize TCR signaling intermediates as candidates for therapeutic targeting.

Post-COVID syndrome in non-hospitalised patients with COVID-19: a longitudinal prospective cohort study

BACKGROUND

While the leading symptoms during coronavirus disease 2019 (COVID-19) are acute and the majority of patients fully recover, a significant fraction of patients now increasingly experience long-term health consequences. However, most data available focus on health-related events after severe infection and hospitalisation. We present a longitudinal, prospective analysis of health consequences in patients who initially presented with no or minor symptoms of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection. Hence, we focus on mild COVID-19 in non-hospitalised patients.

METHODS

958 Patients with confirmed SARS-CoV-2 infection were observed from April 6th to December 2nd 2020 for long-term symptoms and SARS-CoV-2 antibodies. We identified anosmia, ageusia, fatigue or shortness of breath as most common, persisting symptoms at month 4 and 7 and summarised presence of such long-term health consequences as post-COVID syndrome (PCS). Predictors of long-term symptoms were assessed using an uni- and multivariable logistic regression model.

FINDINGS

We observed 442 and 353 patients over four and seven months after symptom onset, respectively. Four months post SARS-CoV-2 infection, 8•6% (38/442) of patients presented with shortness of breath, 12•4% (55/442) with anosmia, 11•1% (49/442) with ageusia and 9•7% (43/442) with fatigue. At least one of these characteristic symptoms was present in 27•8% (123/442) and 34•8% (123/353) at month 4 and 7 post-infection, respectively. A lower baseline level of SARS-CoV-2 IgG, anosmia and diarrhoea during acute COVID-19 were associated with higher risk to develop long-term symptoms.

INTERPRETATION

The on-going presence of either shortness of breath, anosmia, ageusia or fatigue as long-lasting symptoms even in non-hospitalised patients was observed at four and seven months post-infection and summarised as post-COVID syndrome (PCS). The continued assessment of patients with PCS will become a major task to define and mitigate the socioeconomic and medical long-term effects of COVID-19.

FUNDING

COVIM:"NaFoUniMedCovid19"(FKZ: 01KX2021).

Kinetics and correlates of the neutralizing antibody response to SARS-CoV-2 infection in humans

Understanding antibody-based SARS-CoV-2 immunity is critical for overcoming the COVID-19 pandemic and informing vaccination strategies. We evaluated SARS-CoV-2 antibody dynamics over 10 months in 963 individuals who predominantly experienced mild COVID-19. Investigating 2,146 samples, we initially detected SARS-CoV-2 antibodies in 94.4% of individuals, with 82% and 79% exhibiting serum and IgG neutralization, respectively. Approximately 3% of individuals demonstrated exceptional SARS-CoV-2 neutralization, with these “elite neutralizers” also possessing SARS-CoV-1 cross-neutralizing IgG. Multivariate statistical modeling revealed age, symptomatic infection, disease severity, and gender as key factors predicting SARS-CoV-2-neutralizing activity. A loss of reactivity to the virus spike protein was observed in 13% of individuals 10 months after infection. Neutralizing activity had half-lives of 14.7 weeks in serum versus 31.4 weeks in purified IgG, indicating a rather long-term IgG antibody response. Our results demonstrate a broad spectrum in the initial SARS-CoV-2-neutralizing antibody response, with sustained antibodies in most individuals for 10 months after mild COVID-19.

Detection of systemic immunosuppressants in autologous serum eye drops (ASED) in patients with severe chronic ocular graft versus host disease

PURPOSE

Chronic graft versus host disease is a major consequence after allogeneic stem cell transplantation (allo-SCT) and has great impact on patients' morbidity and mortality. Besides the skin, liver, and intestines, the eyes are most commonly affected, manifesting as severe ocular surface disease. Treatment protocols include topical steroids, cyclosporine, tacrolimus, and ASED. Since these patients often receive systemic immunosuppressant therapy from their oncologists, a topical re-administration of these drugs via ASED with potentially beneficial or harmful effects is possible. The purpose of the study was to determine whether and to which extent systemic immunosuppressants are detectable in ASED.

METHODS

A total of 34 samples of ASED from 16 patients with hemato-oncological malignancies after allo-SCT were collected during the manufacturing process and screened for levels of cyclosporine, mycophenolic acid, everolimus, and tacrolimus via liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The study followed the tenets of the Declaration of Helsinki and informed consent was obtained from the subjects after explanation of the nature and possible consequences of the study.

RESULTS

Cyclosporine was found in 18 ASED samples in concentrations ranging from 6.5-105.0 ng/ml (32.0 ± 22.8 ng/ml, mean ± SD). The concentration range of mycophenolic acid in 19 samples was 0.04-25.0 mg/l (4.0 ± 5.4 mg/l, mean ± SD). Everolimus and tacrolimus concentrations were well below the respective limits of quantification (< 0.6 and < 0.5 ng/ml) of the established LC-MS/MS method in all samples.

CONCLUSIONS

Our study suggests that orally administered cyclosporine and mycophenolic acid for the treatment of systemic GvHD, but not everolimus and tacrolimus, are distinctly detectable in ASED in relevant concentrations. It is highly likely that these agents affect topical therapy of ocular GvHD. However, the extent of this effect needs to be evaluated in further studies.

The effect of serum pretreatment regimens for the detection of HLA class I antibodies in platelet-refractory patients

BACKGROUND

Single antigen bead (SAB) assays are used to identify human leukocyte antigen (HLA) antibodies in patients with platelet refractoriness due to HLA Class I alloimmunization. Some laboratories use serum pretreatment regimens to eliminate interference from immunoglobulin M antibodies and complement. These modifications may contribute to interlaboratory variability, which is a recognized problem with the SAB assay.

STUDY DESIGN AND METHODS

Five patients' sera were overnight shipped to 12 laboratories in the United States and internationally. Recipients used their lab's SAB procedure to identify HLA Class I antibodies. The resultant mean fluorescence intensity (MFI) data were compared by instrumentation, bead lot, and pretreatment regimens. Laboratory-specific cutoffs for positive antibodies were applied to the results.

RESULTS

Interlaboratory variability for MFI values appears to be associated with different pretreatment regimens. The coefficient of variation (CV) of MFI from samples pretreated with ethylenediaminetetraacetic acid, dithiothreitol, or heat inactivation (EDHI) were similar, ranging from 14% to 56% (mean, 22%). For samples with no pretreatment, the CVs were significantly higher than EDHI-treated samples, ranging from 25% to 74% (mean, 39%; 95% confidence interval, 12.10-21.90; p < 0.0001). An intralaboratory comparison of pretreatment regimens confirmed these findings. Some positive antibody specificities present in EDHI-treated samples were negative in corresponding samples with no pretreatment when laboratory-specific cutoffs for positive antibodies were applied.

CONCLUSION

Our results show that greater interlaboratory precision can be achieved when samples are pretreated with EDHI as opposed to no pretreatment, likely because these pretreatments eliminate interference from inhibitors. Inhibitors may mask antibodies, leading to missed (or uncalled) specificities when no pretreatment is used.

Tumor-associated B cells and humoral immune response in head and neck squamous cell carcinoma

B lymphocytes are important players in immune responses to cancer. However, their composition and function in head and neck squamous cell carcinoma (HNSCC) has not been well described. Here, we analyzed B cell subsets in HNSCC (n = 38), non-cancerous mucosa (n = 14) and peripheral blood from HNSCC patients (n = 38) and healthy controls (n = 20) by flow cytometry. Intratumoral B cells contained high percentages of activated (CD86+), antigen-presenting (CD86+/CD21-) and memory B cells (IgD-/CD27+). T follicular helper cells (CD4+/CXCR5+/CD45RA-/CCR7-) as key components of tertiary lymphoid structures and plasma cells made up high percentages of the lymphocyte infiltrate. Percentages of regulatory B cell varied depending on the regulatory phenotype. Analysis of humoral immune responses against 23 tumor-associated antigens (TAA) showed reactivity against at least one antigen in 56% of HNSCC patients. Reactivity was less frequent in human papillomavirus associated (HPV+) patients and healthy controls compared to HPV negative (HPV-) HNSCC. Likewise, patients with early stage HNSCC or MHC-I loss on tumor cells had low TAA responses. Patients with TAA responses showed CD4+ dominated T cell infiltration compared to mainly CD8+ T cells in tumors without detected TAA response. To summarize, our data demonstrates different immune infiltration patterns in relation to serological TAA response detection and the presence of B cell subpopulations in HNSCC that can engage in tumor promoting and antitumor activity. In view of increasing use of immunotherapeutic approaches, it will be important to include B cells into comprehensive phenotypic and functional analyses of tumor-associated lymphocytes.

B cells in esophago-gastric adenocarcinoma are highly differentiated, organize in tertiary lymphoid structures and produce tumor-specific antibodies

Tumor-infiltrating lymphocytes (TILs) are correlated to prognosis of several kinds of cancer. Most studies focused on T cells, while the role of tumor-associated B cells (TABs) has only recently gained more attention. TABs contain subpopulations with distinct functions, potentially promoting or inhibiting immune responses. This study provides a detailed analysis of TABs in gastro-esophageal adenocarcinoma (EAC). Flow cytometric analyses of single cell suspensions of tumor samples, mucosa, lymph nodes and peripheral blood mononuclear cells (PBMC) of EAC patients and healthy controls revealed a distinct B cell compartment in cancer patients. B cells were increased in tumor samples and subset-analyses of TILs showed increased proportions of differentiated and activated B cells and an enrichment for follicular T helper cells. Confocal microscopy demonstrated that TABs were mainly organized in tertiary lymphoid structures (TLS), which resemble lymphoid follicles in secondary lymphoid organs. A panel of 34 tumor-associated antigens (TAAs) expressed in EAC was identified based on public databases and TCGA data to analyze tumor-specific B cell responses using a LUMINEXTM bead assay and flow cytometry. Structural analyses of TLS and the detection of tumor-specific antibodies against one or more TAAs in 48.1% of analyzed serum samples underline presence of anti-tumor B cell responses in EAC. Interestingly, B cells were decreased in tumors with expression of Programmed Death Ligand 1 or impaired HLA-I expression. These data demonstrate that anti-tumor B cell responses are an additional and underestimated aspect of EAC. Our results are of immediate translational relevance to emerging immunotherapies.

Enlargement of the WHO international repository for platelet transfusion-relevant bacteria reference strains

BACKGROUND AND OBJECTIVES

Interventions to prevent and detect bacterial contamination of platelet concentrates (PCs) have reduced, but not eliminated the sepsis risk. Standardized bacterial strains are needed to validate detection and pathogen reduction technologies in PCs. Following the establishment of the First International Reference Repository of Platelet Transfusion-Relevant Bacterial Reference Strains (the 'repository'), the World Health Organization (WHO) Expert Committee on Biological Standardisation (ECBS) endorsed further repository expansion.

MATERIALS AND METHODS

Sixteen bacterial strains, including the four repository strains, were distributed from the Paul-Ehrlich-Institut (PEI) to 14 laboratories in 10 countries for enumeration, identification and growth measurement on days 2, 4 and 7 after low spiking levels [10-25 colony-forming units (CFU)/PC bag]. Spore-forming (Bacillus cereusPEI-B-P-07-S, Bacillus thuringiensisPEI-B-P-57-S), Gram-negative (Enterobacter cloacaePEI-B-P-43, Morganella morganiiPEI-B-P-74, PEI-B-P-91, Proteus mirabilisPEI-B-P-55, Pseudomonas fluorescensPEI-B-P-77, Salmonella choleraesuisPEI-B-P-78, Serratia marcescensPEI-B-P-56) and Gram-positive (Staphylococcus aureusPEI-B-P-63, Streptococcus dysgalactiaePEI-B-P-71, Streptococcus bovisPEI-B-P-61) strains were evaluated.

RESULTS

Bacterial viability was conserved after transport to the participating laboratories with one exception (M. morganiiPEI-B-P-74). All other strains showed moderate-to-excellent growth. Bacillus cereus, B. thuringiensis, E. coli, K. pneumoniae, P. fluorescens, S. marcescens, S. aureus and S. dysgalactiae grew to >10⁶ CFU/ml by day 2. Enterobacter cloacae, P. mirabilis, S. epidermidis, S. bovis and S. pyogenes achieved >10⁶ CFU/ml at day 4. Growth of S. choleraesuis was lower and highly variable.

CONCLUSION

The WHO ECBS approved all bacterial strains (except M. morganiiPEI-B-P-74 and S. choleraesuisPEI-B-P-78) for repository enlargement. The strains were stable, suitable for spiking with low CFU numbers, and proliferation was independent of the PC donor.

Treatment of severe chronic ocular graft-versus-host disease using 100% autologous serum eye drops from a sealed manufacturing system: a retrospective cohort study

BACKGROUND/AIMS

To analyse patients with chronic ocular graft-versus-host disease (GvHD) under treatment with 100% autologous serum eye drops from a sealed manufacturing system.

METHODS

17 patients with chronic ocular GvHD received 100% autologous serum eye drops from single use vials manufactured in a sealed system. Retrospective analysis included visual acuity, corneal staining, frequency of artificial tears, ocular symptoms by means of a questionnaire and information on subjective side effects and cost compensation.

RESULTS

Data of prior to autologous serum eye drops therapy and at a 6-month follow-up were obtained. They demonstrated a significant increase in visual acuity (logMAR oculus dexter/right eye (OD) 0.5±0.32 to 0.4±0.3; oculus sinister/left eye (OS) 0.6±0.35 to 0.3±0.35; p=0.177/0.003) and significant improvement in corneal staining (Oxford grading scheme: OD from 3±1.03 to 2±1.43, OS from 4±1.0 to 2±1.09, p=0.004/0.001) and ocular symptoms (ocular surface disease index: 88±20.59 to 63±22.77; p=0.02). Frequency of artificial tears was reduced and no side effects were reported. Patient satisfaction was 100%, and cost compensation by health insurance reached 80%.

CONCLUSIONS

100% autologous serum eye drops using a sealed manufacturing system were efficient in improving the ocular surface, patient symptoms and visual acuity without side effects. It seems to be safe to use 100% autologous serum despite earlier suspicions regarding immune complex accumulations and exacerbation of ocular surface inflammation. The potential effects of serum levels of systemic immunosuppressives through readministration onto the ocular surface need to be elucidated.

ABO-incompatible kidney transplantation using regenerative selective immunoglobulin adsorption

BACKGROUND

ABO-incompatible (ABOi) kidney transplantation is an established procedure relying on the removal of donor-specific isoagglutinine antibodies as part of the recipient preconditioning. At present, current protocols using immunoadsorption apply a single-use selective carbohydrate isoagglutinine adsorber. A regenerative and selective immunoglobulin immunoadsorption could be an alternative but has not been reported for ABOi transplantation.

METHODS

Eight patients were treated with the commonly used isoagglutinine carbohydrate epitope adsorber and seven with a regenerative polyclonal sheep anti-immunoglobulin adsorber as part of the preconditioning for ABOi kidney transplantation. An IgG-isoagglutinine titer of less or equal 1:4 qualified for transplantation. Treatment safety, efficiency, length of desensitization, number of postoperative immunoadsorptions, and allograft outcome were retrospectively compared.

RESULTS

With the use of the immunoglobulin adsorber the median initial isoagglutinine IgG titers of 1:64 (range 1:32-1:256) were lowered to the target of 1:4 preoperatively with a mean of 6.2 immunoadsorptions (range 5-11). Mean IgG/IgM titer step reduction per IA was 1.98/1.21 for (range 0-4/0-4) and mean titer step rebound 1.31/0.82 (range 0-4/0-3), respectively. The number of immunoadsorptions and length of desensitization was not different from the use of the specific isoagglutinine adsorbers. After transplantation, no rejection occurred and only one postoperative immunoadsorption was necessary. No adverse events in relation to immunoadsorption were observed. Graft function was comparable to the isoagglutinine adsorber group.

CONCLUSION

These data suggest that ABOi kidney transplantation can be performed safely and effectively with a selective regenerative immunoglobulin immunoadsorber.

Blood-based gene expression signatures in non-small cell lung cancer

PURPOSE

Blood-based surrogate markers would be attractive biomarkers for early detection, diagnosis, prognosis, and prediction of therapeutic outcome in cancer. Disease-associated gene expression signatures in peripheral blood mononuclear cells (PBMC) have been described for several cancer types. However, RNA-stabilized whole blood-based technologies would be clinically more applicable and robust. We evaluated the applicability of whole blood-based gene expression profiling for the detection of non-small cell lung cancer (NSCLC).

EXPERIMENTAL DESIGN

Expression profiles were generated from PAXgene-stabilized blood samples from three independent groups consisting of NSCLC cases and controls (n = 77, 54, and 102), using the Illumina WG6-VS2 system.

RESULTS

Several genes are consistently differentially expressed in whole blood of NSCLC patients and controls. These expression profiles were used to build a diagnostic classifier for NSCLC, which was validated in an independent validation set of NSCLC patients (stages I-IV) and hospital-based controls. The area under the receiver operator curve was calculated to be 0.824 (P < 0.001). In a further independent dataset of stage I NSCLC patients and healthy controls the AUC was 0.977 (P < 0.001). Specificity of the classifier was validated by permutation analysis in both validation cohorts. Genes within the classifier are enriched in immune-associated genes and show specificity for NSCLC.

CONCLUSIONS

Our results show that gene expression profiles of whole blood allow for detection of manifest NSCLC. These results prompt further development of gene expression-based biomarker tests in peripheral blood for the diagnosis and early detection of NSCLC.

Generation of neutrophil priming activity by cell-containing blood components treated with pathogen reduction technology and stored in platelet additive solutions

BACKGROUND

Storage of cell-containing blood components such as platelet concentrates (PCs) and red blood cells (RBCs) results in generation of biologically active compounds, many of which may be associated with adverse transfusion events. Priming of the neutrophil oxidase activity is a common characteristic of many of the biologically active compounds found in stored blood. We evaluated the priming activity of pathogen reduction technology (PRT)-treated PCs stored in plasma or platelet additive solution (PAS) and PRT-treated RBCs.

STUDY DESIGN AND METHODS

PCs were collected with Trima or Amicus equipment and were PRT treated with the Mirasol PRT system or the Intercept Blood System. Some units were gamma irradiated. Products were stored in 100% plasma or 35% plasma plus PAS. RBCs were washed and PRT treated before storage. Samples were removed throughout storage and priming of the oxidase activity was measured.

RESULTS

Platelets collected on Trima or Amicus equipment and stored in plasma or PAS demonstrated increasing priming activity during 5 to 7 days of storage. Gamma irradiation, but not PRT treatment with either technology, further enhanced this priming activity. Supernatants of RBCs stored for 42 days induced priming in untreated controls, but not in washed or Mirasol PRT-treated test products.

CONCLUSION

Production of oxidase priming activity increased during storage in all blood products. No significant differences were associated with the collection method, storage in PAS, or PRT treatment. The generation of biologically active compounds, which may serve as an etiology for adverse events, appears to be independent of these processes for collection, storage, and pathogen reduction.

Bead array-based microrna expression profiling of peripheral blood and the impact of different RNA isolation approaches

Blood-based mRNA expression profiling has already become an important issue in clinical applications. More recently, the characterization of the small RNA transcriptome offers additional avenues for diagnostic approaches. However, when applying miRNA expression profiling in routine clinical settings, the method of RNA preservation and the manner of RNA extraction as well as the reliability of the miRNA profiling procedure have to be carefully considered. Here we evaluate a recently introduced bead array-based technology as a robust method for the generation of blood-based human miRNA expression profiles. Importantly the comparison of different RNA extraction strategies resulted in dissimilar profiles depending on the RNA extraction method as well as on the underlying source. Expression profiles obtained from peripheral mononuclear cells (PBMCs) substantially differed from those of whole blood samples, whereby both sources per se yielded reproducible and reliable results. Expression profiles were also distinct when using either fresh or frozen PBMCs. Moreover RNA size fractioning resulted in discriminative miRNA expression profiles compared with total RNA based profiles. This study outlines important steps toward the establishment of a robust strategy for blood-based miRNA profiling and provides a reliable strategy for its implementation in routine handling for diagnostic purposes.

Re-operation for complicated secondary peritonitis - how to identify patients at risk for persistent sepsis

INTRODUCTION

There is an ongoing dispute on the benefit of planned relaparotomy for patients with diffuse peritonitis.

SETTING

Surgery Department, university hospital.

PATIENTS

145 patients with diffuse peritonitis treated with planned relaparotomy were analysed for APACHE II, MOF- and MODS-score (Goris and Marshall), complications, outcome and clinical/laboratory factors indicating intra-abdominal compartment syndrome (positive endexpiratory pressure (PEEP), central venous pressure (CVP), creatinine, blood urea nitrogen (BUN)) after termination of planned relaparotomy. Statistical analysis of data (mean and standard deviation) was performed using Mann-Whitney, chi-square, ANOVA and multiple regression analysis.

RESULTS

The overall mortality was 29.7% and APACHE II score on admission 16.7 +/- 8.3. In 107 patients (mortality 17.8%) closure of the abdomen was achieved at termination of planned relaparotomy, 20 patients (mortality 30%) were treated with mesh closure and in 18 patients (mortality 100%) closure of the abdomen was not feasible. After closure of the abdomen 39 patients showed signs of persistent sepsis. Patients who were explored had a mortality of 37.5% and without re-exploration a mortality of 67%. BUN, PEEP and CVP were significantly different in survivors and non-survivors. Independent predictors of outcome were closure of the abdomen, complications, APACHE II and MOF scores.

CONCLUSION

Patients with planned relaparotomy for diffuse peritonitis are not a uniform group and differ in mortality depending on source control and closure of the abdomen. Patients with persistent sepsis after termination of planned relaparotomy may be recognized by clinical and laboratory parameters and benefit from a timely reexploration. The decision when to close the abdomen may not only be based on intraperitoneal findings but also on the existence and level of organ failure.

Prevalence of human T-cell lymphotropic virus infections in Germany

The extent of human T-cell lymphotropic retrovirus HTLV-I and HTLV-II infections in the general population in central Europe has not been investigated fully. Two hundred forty-eight thousand blood donors from southern Germany were examined serologically for antibodies to the human lymphotropic retroviruses HTLV-I and HTLV-II: 0.021% were confirmed positive and 0.056% were "indeterminate". A limited number of seropositives and "indeterminate" samples were analyzed by polymerase chain reaction (PCR): the seropositives were confirmed as positive and 43% of the "indeterminate" samples were PCR-positive. The range of 0.021% HTLV-positives in 248,000 donors, i.e. about two in 10,000 individuals, mirrors closely the published data for the United States.

Uric acid levels in southern Germany in 1989. A comparison with studies from 1962, 1971, and 1984

Since 1962 our group has performed four studies on uric acid values in blood donors in southern Germany (Bavaria). Uric acid levels in men have increased over the years, from 4.86 mg/dl in 1962 to 6.00 mg/dl in 1971, 5.60 mg/dl in 1984, and 5.90 mg/dl in 1989. Levels in women have increased slightly, from 4.05 mg/dl in 1962 to 4.35 mg/dl in 1971, 4.10 mg/dl in 1984, and 4.16 mg/dl in 1989. Women aged 51 to 60 years had significantly higher uric acid levels than those in the fourth decade. In women treated with oral contraceptives uric acid levels were significantly lower than in other women of the same age. Hypouricemia (uric acid levels less than or equal to 2.0 mg/dl) was observed in three women, none of whom had a history of medication. Hyperuricemia exists when uric acid levels are greater than or equal to 6.5 mg/dl. In 1989 2.6% of the female blood donors and 28.6% of the males were hyperuricemic, with an increased risk of gout, nephrolithiasis, and nephropathy.

Erythrocyte antibodies in AIDS are associated with mycobacteriosis and hypergammaglobulinemia

Positive direct antiglobulin results prior to transfusion in some of our AIDS patients, as well as some reports in the literature on red cell antibodies in AIDS patients, prompted us to investigate the prevalence of erythrocyte antibodies in AIDS patients with transfusion requiring anemia. In addition we studied the question of relevant correlations with clinical diagnosis and with hematological and immunological laboratory parameters. Of 145 consecutive hospitalized AIDS patients (CDC criteria), 34 (23%) presented with anemia requiring transfusion. With each cross-match a routine antibody screening was performed. In cases of positive reaction additional antibody differentiation was done. Diagnoses, hematologic parameters, and therapy were studied retrospectively. Agglutination was positive in at least one test for 41% (14/34) (group 1). C3d, anti I, cold agglutinins, and IgG occurred most frequently (n = 9/8/7/6 out of 14). Seventy-five per cent (12/14) had leukopenia (less than 4000/microliters), 57% (8/14) had thrombocytopenia (less than 150,000/microliters), and 43% (6/14) showed both. Average values for leukocytes, thrombocytes, and CD4-positive lymphocytes did not differ significantly in patients with (group 1) and without (group 2) erythrocyte antibodies. Average gamma globulin levels were significantly increased in group 1 (23.2 g/l versus 16.9 g/l; p less than 0.001). In group 1, 64% (9/14) had proven mycobacteriosis (6 atypical), in contrast to only 15% (3/20) in group 2 (p less than 0.05). There were no significant differences between the two groups in prevalence of other opportunistic infections, malignant lymphoma, and Kaposi's sarcoma. Autoimmune versus infectious pathogenesis of pathologic erythrocyte antibodies in AIDS has been discussed in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk of HIV infection from former blood donations of donors found to be HIV antibody-positive in blood bank routine testing. "Look-back" study in German Red Cross Blood Banks in the FRG

Recipients of blood given by 52 repeat blood donors found to be positive by Western blot analysis for anti-HIV from April 1985 to December 1987, among a total of 1.6 million blood donors in the German Red Cross Blood Banks in the FRG, were investigated. Of 149 recipients identified, 76 (51%) had died. Ten recipients refused to be tested. Of those recipients who were tested at least 5 months after transfusion, 46 were HIV antibody negative and 17 were Western blot-positive. In 14 of the HIV antibody-positive recipients, transfusion was given during the period from 1982 to the begin of routine testing in 1985. Three recipients of HIV antibody-negative donations were subsequently identified as HIV positive. The blood had been donated a median of 3 months before HIV antibodies were detected in the donors. From a total of 3 million donations since testing has been introduced, the risk of HIV transmission in tested blood is 1:1 million in our donor population where the HIV antibody prevalence (in Western blot) is about 1 per 100,000 donations/donors.