Risk of dementia among older patients with lymphoma: A Danish nationwide matched cohort study.

INTRODUCTION: Treatment of lymphoma can be associated with cognitive challenges, and some patients may fear development of dementia as long-term complication. Studies report a lower risk of dementia after cancer. Some believe this difference to be a protective mechanism of cancer, others believe it to be driven by bias. The risk of developing dementia after lymphoma has not been investigated in a population-based setting. The aim of this study was to identify the risk of being diagnosed with dementia after lymphoma treatment. MATERIALS AND METHODS: This Danish nationwide matched cohort study included patients aged ≥65 years with a first-time diagnosis of a non-central nervous system lymphoma between 2005 and 2018 in complete remission after treatment with chemotherapy. Patients diagnosed with dementia or treated with dementia medication before lymphoma diagnosis were excluded. Each patient was matched 1:5 on sex, year of birth, and a modified Charlson comorbidity index. Patients and matched comparators were followed from the corresponding patient's date of complete remission. The risk of developing dementia was calculated using cause-specific hazard ratios (HR), and the cumulative risk was estimated by Aalen-Johansen with death as the competing risk. RESULTS: A total of 3,244 patients and 16,220 matched comparators were included in the study. There was no difference in risk of all-cause dementia among patients with lymphoma compared to matched comparators with cause-specific HR of 0.85 (95% confidence interval [CI]: 0.70;1.04). The risk of both Alzheimer's disease and non-Alzheimer's dementia was equal among patients and comparators: HR 0.89 (95% CI: 0.66;1.21) and 0.82 (95% CI: 0.63;1.07), respectively. Stratified by lymphoma subtype, age, or year of diagnosis, the risk of all-cause dementia remained equal among patients and matched comparators. The cumulative risk of all-cause dementia was significantly lower among patients with lymphoma compared to matched comparators (Gray's test p < 0.001), probably reflecting higher mortality in patients with lymphoma. DISCUSSION: The risk of all-cause dementia, Alzheimer's disease, and non-Alzheimer's dementia was equal among older patients with lymphoma compared to matched comparators. Our data suggests that risk of developing dementia is not changed after lymphoma treatment.

Real-world outcomes following third or subsequent lines of therapy: A Danish population-based study on 189 patients with relapsed/refractory large B-cell lymphomas.

Outcome data of patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) beyond the second line are scarce outside of clinical trials. Novel therapies in the R/R setting have been approved based on single-arm trials, but results need to be contextualized by real-world outcomes. Medical records from 3753 Danish adults diagnosed with DLBCL were reviewed. Patients previously treated with rituximab and anthracycline-based chemotherapy who received the third or later line (3 L+) of treatment after 1 January 2015, were included. Only 189 patients with a median age of 71 years were eligible. The median time since the last line of therapy was 6 months. Patients were treated with either best supportive care (22%), platinum-based salvage therapy (13%), low-intensity chemotherapy (22%), in clinical trial (14%) or various combination treatments (32%). The 2-year OS-/PFS estimates were 25% and 12% for all patients and 49% and 17% for those treated with platinum-based salvage therapy. Age ≥70, CNS involvement, elevated LDH and ECOG ≥2 predicted poor outcomes, and patients with 0-1 of these risk factors had a 2-year OS estimate of 65%. Only a very small fraction of DLBCL patients received third-line treatment and were eligible for inclusion. Outcomes were generally poor, but better in intensively treated, fit young patients with limited disease.

Men treated with BEACOPP for Hodgkin lymphoma may be at increased risk of testosterone deficiency.

In the current study, we report the prevalence of male testosterone deficiency in a cohort of 60 male long-term survivors of malignant lymphoma with normal total testosterone but in the lower part of the reference level. Testosterone deficiency was defined as subnormal concentrations of total testosterone or subnormal concentrations of calculated free testosterone. The aim was to clarify whether total testosterone was sufficient for identification of testosterone deficiency in male survivors of malignant lymphoma. Hormonal analyses taken at follow-up were compared with samples taken at diagnosis for a subgroup of 20 survivors, for evaluation of changes in hormones over time. Another group of 83 similar survivors of malignant lymphoma with testosterone in the high end of reference levels were also used for comparison, to identify groups of increased risk of testosterone deficiency. A total group of 143 survivors were therefore included in the study. Our findings indicate that for screening purposes an initial total testosterone is sufficient in some survivors because sexual hormone binding globulin concentration was found stable over time. However, 15% were found with subnormal calculated free testosterone. Survivors intensely treated for Hodgkin lymphoma and older survivors were identified as high-risk groups for testosterone deficiency necessitating endocrinological attention during follow-up. Some evidence of pituitary downregulation was also found, because of uncompensated decreases in testosterone concentration over time. In conclusion, longitudinal measurements of total testosterone alone do not seem adequate for the screening of testosterone deficiency for all long-term lymphoma survivors.

Next generation sequencing in routine diagnostics of mature non-Hodgkin's B-cell lymphomas.

INTRODUCTION: Integration of molecular characterization of lymphomas in clinical diagnostics may improve subclassification and risk-stratification, and we implemented a next generation sequencing (NGS) analysis as part of routine diagnostic work-up of all mature B-cell non-Hodgkin's lymphoma (B-NHL). Here, we present data of mutational profiles with potential complementary diagnostic, prognostic, and predictive value detected in our consecutive non-selected cohort of B-NHL patients. METHODS: NGS results from 298 patients with both newly diagnosed and relapsed/refractory disease were included as a single center study. NGS was performed as routine analysis together with standard diagnostic work-up using a custom-made amplicon PCR-based multiplex NGS panel covering all coding exons and consensus splice sites in 59 genes. RESULTS: Mutations were detected in 94% of the 298 samples. Most lymphomas could be classified definitively, but 24 cases were classified as small B-cell lymphomas without defining characteristics. Of these, 50% (12/24 cases) could retrospectively be assigned a likely diagnostic subtype according to mutational findings. CONCLUSION: Implementation of a 59 gene exome sequencing panel added diagnostic value to 50% of unclassified cases and provided in 94% of the cases possible biomarkers for disease monitoring as well as potential diagnostic, prognostic, and predictive markers for future studies.

Multi-site pre-therapeutic biopsies demonstrate genetic heterogeneity in patients with newly diagnosed diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, both regarding clinical presentation, response to treatment and outcome. Recently, subclassification of DLBCL based on mutational profile has been suggested, and next generation sequencing (NGS) analysis may be relevant as part of the diagnostic workflow. This will, however, often be based on analysis of one tumor biopsy. Here, we present a prospective study where multi-site sampling was performed prior to treatment in patients with newly diagnosed DLBCL. Two spatially different biopsies from 16 patients were analyzed using NGS with an in-house 59-gene lymphoma panel. In 8/16 (50%) patients, mutational differences were found between the two biopsy sites, including differences in TP53 mutational status. Our data indicate that a biopsy from the extra-nodal site may represent the most advanced clone, and an extra-nodal biopsy should be preferred for analysis, if safely accessible. This will help ensure a standardized stratification and treatment decision.

Humoral and cellular immune responses after three or four doses of BNT162b2 in patients with hematological malignancies.

OBJECTIVES: Initial responses to coronavirus disease 2019 vaccination are impaired in patients with hematological malignancies. We investigated immune responses after three or four doses of BNT162b2 in patients with myeloid and lymphoid malignancies compared to controls, and identified risk factors for humoral and cellular nonresponse 1 year after first vaccination. METHODS: In 407 hematological patients (45 myeloid, 362 lymphoid) and 98 matched controls, we measured immunoglobulin G (IgG) and neutralizing antibodies specific for the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at baseline, 3 weeks, 2, 6, and 12 months, and interferon-γ release at 12 months. RESULTS: In patients with lymphoid malignancies, SARS-CoV-2 receptor-binding domain IgG concentration and mean neutralizing capacity was lower than in controls at all time points. A diagnosis of chronic lymphocytic B-cell leukemia (CLL) or lymphoma was associated with humoral nonresponse at 12 months compared to having multiple myeloma/amyloidosis (p < .001 and p = .013). Compared to controls, patients with lymphoid malignancies had increased risk of cellular nonresponse. A lymphoma diagnosis was associated with lower risk of cellular nonresponse compared to patients with multiple myeloma/amyloidosis, while patients with CLL had comparable response rates to patients with multiple myeloma/amyloidosis (p = .037 and p = .280). CONCLUSIONS: In conclusion, long-term humoral and cellular immune responses to BNT162b2 were impaired in patients with lymphoid malignancies.

Sexual dysfunction is highly prevalent in male survivors of malignant lymphoma.

Background: With improved survival in patients with lymphoma, long-term toxicity and quality of life (QoL), including sexual health, have become increasingly important. Aim: We aimed to (1) determine the prevalence of erectile dysfunction (ED) in adult male lymphoma survivors; (2) determine whether testosterone deficiency, comorbidities, or lifestyle factors were associated; and (3) evaluate their impact on QoL. Methods: A cross-sectional study including 172 male survivors of Hodgkin lymphoma or diffuse large B cell lymphoma diagnosed in adulthood between 2008 and 2018 was performed. Patients were in complete metabolic remission after first-line treatment and remained in remission at follow-up (3-13 years after diagnosis). Participants completed 3 questionnaires measuring sexual health and general QoL. Serum concentrations of total testosterone were measured and thorough medical history and sociodemographic factors were obtained. The Danish SEXUS Project, European Male Ageing Study, and European Organization of Research and Treatment of Cancer (EORTC) Reference Manual were used as reference values of the general population. Outcomes: Patient reported outcome measures including the 5-item International Index of Erectile Function, EORTC C30, and EORTC 22-item Sexual Health Questionnaire. Results: ED was reported by 55.2%, which was higher than in an age-matched Danish population cohort (17.5%). Erectile function score (5-item International Index of Erectile Function) was negatively associated with comorbidity, body mass index, smoking, and age and positively with the number of children conceived before treatment and serum concentration of total testosterone. Overt testosterone deficiency in combination with ED was detected in 10 (5.7%) of 176 survivors, including excluded survivors in hormonal treatment, which is higher than for the general population (0.1%-3.2% for men <70 years of age). Mean EORTC C30 global health score for survivors with ED was lower (67.7) than for survivors without ED (80.1) but was comparable to the general population (71.2). Furthermore, a positive association was seen between sexual function and both sexual and general QoL. Clinical implications: Sexual health is important for QoL and related to comorbidities. The focus on improving QoL requires that both sexual health and comorbidities are addressed in the follow-up of lymphoma patients. Strengths and limitations: Despite the relatively high number of included survivors, the cross-sectional design of this study warrants longitudinal studies to clarify the specific underlying causes of sexual dysfunction. Conclusion: ED was highly prevalent and associated with comorbidity in lymphoma survivors, and more focus on sexual health and treatment related comorbidity is needed to improve sexual and general QoL.

Work Disability and Return to Work After Lymphoma: A Danish Nationwide Cohort Study.

Purpose: Many patients diagnosed with lymphoma are of working age. Cancer patients are known to have a higher risk of sick leave and disability pension, but this has only been delineated for certain subtypes of lymphoma. Therefore, this study aimed at investigating the overall risk of disability pension for all lymphoma subtypes and at quantifying return to work for patients with lymphoma in work before diagnosis. Patients and Methods: Patients aged 18-60 years with lymphoma in complete remission (CR) diagnosed between 2000 and 2019 were included in the study. Using national registers, each patient was matched with five comparators from the general population with same sex, birth year, and level of Charlson Comorbidity Index. Risk of disability pension was calculated from 90 days after CR or end of treatment with competing events (death, retirement pension, early retirement pension, relapse for patients, or lymphoma diagnosis for comparators). Return to work for patients was calculated annually until 5 years after diagnosis for patients employed before diagnosis. Results: In total, 4072 patients and 20,360 comparators were included. There was a significant increased risk of disability pension for patients with all types of lymphoma compared to the general population (5-year risk difference: 5.3 (95% confidence interval (CI): 4.4;6.2)). Patients with non-Hodgkin lymphoma were more likely to get disability pension than patients with Hodgkin lymphoma (sex- and age-adjusted 10-year risk difference: 2.9 (95% CI: 0.3;5.5)). One year after diagnosis, 24.5% of the relapse-free patients were on sick leave. Return to work was highest 2 years after diagnosis (82.1%). Conclusion: Patients with lymphoma across all subtypes have a significantly higher risk of disability pension. Return to work peaks at 2 years after diagnosis.

Erratum: Author Correction: Early stimulated immune responses predict clinical disease severity in hospitalized COVID-19 patients.

[This corrects the article DOI: 10.1038/s43856-022-00178-5.].

Humoral Immune Responses after an Omicron-Adapted Booster BNT162b2 Vaccination in Patients with Lymphoid Malignancies.

To accommodate waning COVID-19 vaccine immunity to emerging SARS-CoV-2 variants, variant-adapted mRNA vaccines have been introduced. Here, we examine serological responses to the BA.1 and BA.4-5 Omicron variant-adapted BNT162b2 COVID-19 vaccines in people with lymphoid malignancies. We included 233 patients with lymphoid malignancies (chronic lymphocytic B-cell leukemia: 73 (31.3%), lymphoma: 89 (38.2%), multiple myeloma/amyloidosis: 71 (30.5%)), who received an Omicron-adapted mRNA-based COVID-19 vaccine. IgG and neutralizing antibodies specific for the receptor-binding domain (RBD) of SARS-CoV-2 were measured using ELISA-based methods. Differences in antibody concentrations and neutralizing capacity and associations with risk factors were assessed using mixed-effects models. Over the period of vaccination with an Omicron-adapted COVID-19 vaccine, the predicted mean concentration of anti-RBD IgG increased by 0.09 log10 AU/mL/month (95% CI: 0.07; 0.11) in patients with lymphoid malignancies across diagnoses. The predicted mean neutralizing capacity increased by 0.9 percent points/month (95% CI: 0.2; 1.6). We found no associations between the increase in antibody concentration or neutralizing capacity and the variant included in the adapted vaccine. In conclusion, a discrete increase in antibody concentrations and neutralizing capacity was found over the course of Omicron-adapted vaccination in patients with lymphoid malignancies regardless of the adapted vaccine variant, indicating a beneficial effect of Omicron-adapted booster vaccination in this population.

Anti-PD-L1/PD-L2 therapeutic vaccination in untreated chronic lymphocytic leukemia patients with unmutated IgHV.

Chronic lymphocytic leukemia (CLL) patients with unmutated immunoglobulin heavy chain (IgHV) are at risk of early disease progression compared to patients with mutated IgHV. As a preventive strategy, we treated 19 previously untreated CLL patients with unmutated IgHV in a phase 1/2 trial (clinicaltrials.gov, NCT03939234) exploring the efficacy and toxicity of a therapeutic cancer vaccine containing peptides derived from programmed death ligand 1 (PD-L1) and ligand 2 (PD-L2), hoping to restore immunological control of the disease. According to the International Workshop on Chronic lymphocytic Leukemia (iwCLL) response criteria, no patients obtained a response; however, during follow-up, one patient had complete normalization of the peripheral lymphocyte count and remained in biochemical remission after a follow-up time of 15 months. At the end of treatment, one patient had progressed, and 17 patients had stable disease. During follow-up with a median time of 23.5 months since inclusion, seven patients had progressed, and eight patients had stable disease. The median time to first treatment (TTFT) from diagnosis was 90.3 months with a median follow-up time of 50.1 months. This apparent favorable outcome in TTFT needs to be investigated in a randomized setting, as our population may have been biased. More than 80% of patients obtained vaccine-specific immune responses, confirming the immunogenicity of the vaccine. The vaccine was generally well tolerated with only grade I-II adverse events. Although there were some signs of clinical effects, the vaccine seems to be insufficient as monotherapy in CLL, possibly due to a high tumor burden. The efficacy of the vaccine should preferably be tested in combination with novel targeted therapies or as a consolidating treatment.

Inactivating BTK mutations in large B-cell lymphoma in a real-world cohort: Strong correlation with BCL2 translocation.

Inactivating mutations in Bruton's tyrosine kinase (BTK) in patients with follicular lymphoma (FL) have recently been reported. These mutations were found in BTK inhibitor-treatment naïve patients. Here, we report the BTK mutation status in a real-world cohort of patients with non-Hodgkin lymphoma. We found primary BTK mutations in 7.7% of patients with large B-cell lymphoma (LBCL) and in 14.1% of patients with FL. All patients with BTK-mutated LBCL were BCL2 translocation positive, and the correlation between BCL2 translocation and BTK mutation persisted even when patients with known transformation from FL were excluded.

Early stimulated immune responses predict clinical disease severity in hospitalized COVID-19 patients.

Background: The immune pathogenesis underlying the diverse clinical course of COVID-19 is poorly understood. Currently, there is an unmet need in daily clinical practice for early biomarkers and improved risk stratification tools to help identify and monitor COVID-19 patients at risk of severe disease. Methods: We performed longitudinal assessment of stimulated immune responses in 30 patients hospitalized with COVID-19. We used the TruCulture whole-blood ligand-stimulation assay applying standardized stimuli to activate distinct immune pathways, allowing quantification of cytokine responses. We further characterized immune cell subsets by flow cytometry and used this deep immunophenotyping data to map the course of clinical disease within and between patients. Results: Here we demonstrate impairments in innate immune response pathways at time of COVID-19 hospitalization that are associated with the development of severe disease. We show that these impairments are transient in those discharged from hospital, as illustrated by functional and cellular immune reconstitution. Specifically, we identify lower levels of LPS-stimulated IL-1ß, and R848-stimulated IL-12 and IL-17A, at hospital admission to be significantly associated with increasing COVID-19 disease severity during hospitalization. Furthermore, we propose a stimulated immune response signature for predicting risk of developing severe or critical COVID-19 disease at time of hospitalization, to validate in larger cohorts. Conclusions: We identify early impairments in innate immune responses that are associated with subsequent COVID-19 disease severity. Our findings provide basis for early identification of patients at risk of severe disease which may have significant implications for the early management of patients hospitalized with COVID-19.

Risk of diabetes and the impact on preexisting diabetes in patients with lymphoma treated with steroid-containing immunochemotherapy.

First-line treatments for lymphomas often include high doses of prednisolone, but the risks of new-onset diabetes mellitus (DM) or worsening of preexisting DM following treatment with cyclic high dose corticosteroids is unknown. This cohort study matched non-Hodgkin lymphoma (NHL) patients treated with steroid-containing immunochemotherapy (ie, R-CHOP[-like] and R-CVP) between 2002 and 2015 to individuals from the Danish population to investigate the risks of new-onset DM. For patients with preexisting DM, the risks of insulin dependency and anthracycline-associated cardiovascular diseases (CVDs) were assessed. In total, 5672 NHL patients and 28 360 matched comparators were included. Time-varying incidence rate ratios (IRRs) showed increased risk of DM in the first year after treatment compared with matched comparators, with the highest IRR being 2.7. The absolute risks were higher among patients in the first 2 years, but the difference was clinically insignificant. NHL patients with preexisting DM had increased risks of insulin prescriptions with 0.5-, 5-, and 10-year cumulative risk differences of insulin treatment of 15.3, 11.8, and 6.0 percentage units as compared with the DM comparators. In a landmark analysis at 1 year, DM patients with lymphoma had decreased risks of insulin dependency compared with comparators. Time-varying IRRs showed a higher CVD risk for NHL patients with DM as compared with comparators in the first year after treatment. NHL patients treated with steroid-containing immunochemotherapy regimens have a clinically insignificant increased risk of DM in the first year following treatment, and patients with preexisting DM have a temporary increased risk of insulin prescriptions and CVD.

Cardiovascular diseases in elderly survivors of diffuse large B-cell lymphoma: a Danish population-based cohort study.

Diffuse large B-cell lymphoma is an aggressive disease occurring primarily in elderly patients. Despite high curative rates with doxorubicin-containing treatment, some elderly patients receive less intensive treatments, mainly due to advanced age, comorbidities, and concerns of cardiotoxicity from doxorubicin-containing regimens. We analyzed 1009 patients aged 75 years or older and 10,090 age- and sex-matched comparisons. We aimed to evaluate long-term cardiovascular side effects in elderly patients treated with doxorubicin. Approximately, 64% of patients received doxorubicin-containing treatment. These patients had a persistently increased risk of new-onset heart failure with a hazard ratio of 1.5 and 1.7 when conditioning on survival without heart failure to 6 and 24 months, respectively. Moreover, we observed an increased risk of venous thromboembolism during the first six months following the lymphoma diagnosis. On the contrary, no difference in risk of developing ischemic heart disease or stroke following doxorubicin-containing treatment was observed.

Patients in complete remission after R-CHOP(-like) therapy for diffuse large B-cell lymphoma have limited excess use of health care services in Denmark.

For most patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), R-CHOP immunochemotherapy leads to complete remission and 60-70% of patients remain progression-free after 5 years. Given a median age of 65, it is relevant to disentangle how DLBCL and DLBCL therapy influence health care use among the survivors. In this nationwide study, the health care use among Danish DLBCL patients diagnosed in 2007-2015, who achieved complete remission after R-CHOP(-like) therapy, was explored and compared to matched comparators from the Danish general population. The post-remission 5-year risk of hospitalization was significantly higher among DLBCL survivors (55%) compared to matched comparators (49%, P < 0.001). DLBCL survivors had on average 10.3 (9.3-11.3) inpatient bed days within 5 years of response evaluation, whereas matched comparators had 8.4 (7.9-8.8). The rate of outpatient visits was also significantly higher(excluding routine follow-up visits, incidence rate ratio, 1.3, P < 0.001), but translated into only a very small absolute difference of <1 outpatient visits within 5 years between DLBCL survivors (4.2 visits, 95% CI, 4.0-4.4) and matched comparators (3.8 visits, 95% CI, 3.7-3.9). In conclusion, DLBCL survivors have an increased incidence of hospital visits due to a wide range of conditions, but in absolute terms the excess use of health care services in DLBCL survivors was small.

Epigenetic therapy in combination with a multi-epitope cancer vaccine targeting shared tumor antigens for high-risk myelodysplastic syndrome - a phase I clinical trial.

BACKGROUND: Standard care for patients with high-risk myelodysplastic syndrome (MDS) is hypomethylating agents such as azacitidine (AZA), which can induce expression of methylated tumor-associated antigens and therefore potentiate immunotherapeutic targeting. METHOD: In this phase 1 trial, we combined AZA with a therapeutic peptide vaccine targeting antigens encoded from NY-ESO-1, MAGE-A3, PRAME, and WT-1, which have previously been demonstrated to be upregulated by AZA treatment. RESULT: Five patients who had responded to AZA monotherapy were included in the study and treated with the vaccine. The combination therapy showed only few adverse events during the study period, whereof none classified as serious. However, no specific immune responses could be detected using intracellular cytokine staining or ELISpot assays. Minor changes in the phenotypic composition of immune cells and their expression of stimulatory and inhibitory markers were detected. All patients progressed to AML with a mean time to progression from inclusion (TTP) of 5.2 months (range 2.8 to 7.6). Mean survival was 18.1 months (range 10.9 to 30.6) from MDS diagnosis and 11.3 months (range 4.3 to 22.2) from inclusion. Sequencing of bone marrow showed clonal expansion of malignant cells, as well as appearance of novel mutations. CONCLUSION: The patients progressed to AML with an average time of only five months after initiating the combination therapy. This may be unrelated to the experimental treatment, but the trial was terminated early as there was no sign of clinical benefit or immunological response. Why the manuscript is especially interesting This study is the first to exploit the potential synergistic effects of combining a multi-peptide cancer vaccine with epigenetic therapy in MDS. Although our results are negative, they emphasize challenges to induce immune reactivity in patients with high-risk MDS.

Three doses of BNT162b2 COVID-19 mRNA vaccine establish long-lasting CD8+ T cell immunity in CLL and MDS patients.

Patients with hematological malignancies are prioritized for COVID-19 vaccine due to their high risk for severe SARS-CoV-2 infection-related disease and mortality. To understand T cell immunity, its long-term persistence, and its correlation with antibody response, we evaluated the BNT162b2 COVID-19 mRNA vaccine-specific immune response in chronic lymphocytic leukemia (CLL) and myeloid dysplastic syndrome (MDS) patients. Longitudinal analysis of CD8+ T cells using DNA-barcoded peptide-MHC multimers covering the full SARS-CoV-2 Spike-protein (415 peptides) showed vaccine-specific T cell activation and persistence of memory T cells up to six months post-vaccination. Surprisingly, a higher frequency of vaccine-induced antigen-specific CD8+ T cells was observed in the patient group compared to a healthy donor group. Furthermore, and importantly, immunization with the second booster dose significantly increased the frequency of antigen-specific CD8+ T cells as well as the total number of T cell specificities. Altogether 59 BNT162b2 mRNA vaccine-derived immunogenic responses were identified, of which 23 established long-term CD8+ T cell memory response with a strong immunodominance for NYNYLYRLF (HLA-A24:02) and YLQPRTFLL (HLA-A02:01) epitopes. In summary, we mapped the vaccine-induced antigen-specific CD8+ T cells and showed a booster-specific activation and enrichment of memory T cells that could be important for long-term disease protection in this patient group.

A user's guide to multicolor flow cytometry panels for comprehensive immune profiling.

Multicolor flow cytometry is an essential tool for studying the immune system in health and disease, allowing users to extract longitudinal multiparametric data from patient samples. The process is complicated by substantial variation in performance between each flow cytometry instrument, and analytical errors are therefore common. Here, we present an approach to overcome such limitations by applying a systematic workflow for pairing colors to markers optimized for the equipment intended to run the experiments. The workflow is exemplified by the design of four comprehensive flow cytometry panels for patients with hematological cancer. Methods for quality control, titration of antibodies, compensation, and staining of cells for obtaining optimal results are also addressed. Finally, to handle the large amounts of data generated by multicolor flow cytometry, unsupervised clustering techniques are used to identify significant subpopulations not detected by conventional sequential gating.