Immunotherapy: ALLOGENEIC UMBILICAL CORD BLOOD REGULATORY T CELLS DECREASE INFLAMMATION AND PRESERVE ANTI-TUMOR ACTIVITY OF CAR T CELLS

Background & Aim: With larger accessibility and increased number of patients being treated with CART cell therapy, real-world toxicity continues to remain a significant challenge to its widespread adoption. We have previously shown that allogeneic umbilical cord blood derived (UCB) regulatory T cells (Tregs) can resolve uncontrolled inflammation and can treat acute and immune mediated lung injury in a xenogenic model as well as in patients suffering from COVID-19 acute respiratory distress syndrome. The unique properties of UCB Tregs including: i) lack of plasticity when exposed to inflammatory micro-environments;ii) no requirement for HLA matching;iii) long shelf life of cryopreserved Tregs;and iv) immediate product availability for on demand treatment, makes them an attractive source for treating acute inflammatory syndromes. Therefore, we hypothesized that add-on therapy with UCB derived Tregs may resolve uncontrolled inflammation responsible for CART cell therapy associated toxicity. Methods, Results & Conclusion(s): UCB Tregs were added in 1:1 ratio to CART cells, where no interference in their ability to kill CD19+ Raji cells, was detected at different ratios : 8:1 (80.4% vs. 81.5%);4:1 (62.0% vs. 66.2%);2:1 (50.1% vs. 54.7%);1:1 (35.4% vs. 44.1%) (Fig 1A). In a xenogenic B cell lymphoma model, multiple injections of Tregs were administered after CART injection (Fig 1B), which did not impact distribution of CD8+ T effector cells (Fig 1C) or CART cells cells (Fig 1D) in different organs. No decline in the CAR T levels was observed in the Tregs recipients (Fig 1E). Specifically, no difference in tumor burden was detected between the two arms (Fig 2A). No tumor was detected in CART+Tregs in liver (Fig 2B) or bone marrow (Fig 2C). A corresponding decrease in multiple inflammatory cytokines in peripheral blood was observed in CART+Tregs when compared to CART alone (Fig 2D). Here we show "proof of concept" for add-on therapy with Tregs to mitigate hyper-inflammatory state induced by CART cells without interference in their on-target anti-tumor activity. The timing of Tregs administration after CART cells have had sufficient time for forming synapse with tumor cells allows for preservation of their anti-tumor cytotoxicity, such that the infused Tregs home to the areas of tissue damage to bind to the resident antigen presenting cells which in turn collaborate with Tregs to resolve inflammation. Such differential distribution of cells allow for a Treg "cooling blanket" and lays ground for clinical study. [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

Characterization of Adaptive Immune Responses to SARS-CoV-2 Updated Bivalent Booster

Bivalent COVID-19 vaccines that contain two mRNAs encoding Wuhan-1 and Omicron BA.4/5 spike proteins are successful in preventing infection from the original strain and Omicron variants, but the quality of adaptive immune responses is still not well documented. This study aims at characterizing adaptive immune responses to the bivalent booster vaccination in 46 healthy participants. Plasma and PBMC were collected prior and three weeks after bivalent booster. We measured anti-N, anti-S, and RBD IgM, IgA, IgG plasma titers against original, Omicron BA.1, and BA.5 variants (pending) as well as total anti-S IgG titers and surrogate Virus Neutralization capacity against the Alpha, Delta, and BA.1 variant. With spectral flow-cytometry we identified peripheral blood B-cells specific for the RBD of the S-protein of the original and BA.1 variants. T-cell-specific responses were assessed by cytokine release assay after stimulation with SARS-CoV-2 peptides from the original, BA.1, BA.4, and BA.5 variants (pending). Finally, we performed TRB and IGH repertoire studies on sorted CD4+, CD8+, CD19+ lymphocytes, to study breadth of SARS-CoV-2 specific clonotypes (pending). 27/46 participants were analyzed;9 had SARS-CoV-2 infection (COVID+), while 18 are infection naive (COVID-). In both groups, median time since last dose of SARS-CoV-2 vaccine (3rd or 4th) was 11 months. All subjects were positive for anti-S IgG prior to bivalent booster. The COVID + group displayed anti-S IgG pre-booster levels and neutralization against BA.1 higher than the COVID- group. Significant increase post-boost of total anti-S IgG and BA.1 neutralizing activity was detected in the COVID- but not in the COVID+ group;however, no difference in neutralization activity post-boost was detected between the two groups. Furthermore, the COVIDgroup showed significant increase in the frequency of CD19+ and CD27+ switched memory B-cells specific for BA.1 RBD in post-boost compared to pre-boost samples. However, post-boost frequencies of the same B-cells were higher in the COVID+ compared to the COVID- group. These preliminary findings confirm that among individual immunized with the original COVID-19 mRNAvaccine, prior COVID infection provides increased protection against SARS-CoV-2 variants. They also demonstrate that booster immunization with the bivalent vaccine induces robust adaptive immune responses against Omicron variant.[Formula presented][Formula presented]Copyright © 2023 Elsevier Inc.

Case Report of Succesful Multidisiplinary Treatment for Patient with Metastatic Lung Cancer and Relapsed/Refractory Chronic Lymphatic Leukemia/Small Lymphocytic Lymphoma

Introduction: Croatian National Cancer Registry of Croatian Institute for Public Health reported that in year 2020 lung cancer was the second most common cancer site diagnosed in men with 16% and the third most common in women with 10% incidence among all cancer sites. Unfortunatelly lung cancer has the highest mortality in both men and women. Haematological malignancies had 7% share in all malignancies in both male and female cances cases. In 2020 190 newly diagnosed cases of lymphatic leukemia in men and 128 cases in women were reporeted, meaning 1.5 and 1.2% of all malignancies, respectively. Chronic lymphatic leukemia (CLL) is an advanced age disease and incidence increases with age. Impaired immunity, T and B cell dysfunction in CLL, chromosomal aberations, long-term immunosuppressive therapy and genetic factors can all cause secondary malignancies. Co- occurence of solid tumors and CLL is very rare. Although patiens with CLL have an increased risk of developing second primary malignancies including lung carcinoma, the data about their clinical outcomes are lacking. Parekh et al. retrospectively analyzed patients with simultaneous CLL and lung carcinoma over a 20-year period, and they found that ~2% of patients with CLL actually developed lung carcinoma. The authors claimed that up to 38% of patients will also develop a third neoplasm more likely of the skin (melanoma and basal cell carcinoma), larynx (laryngeal carcinoma) or colon. Currently there are no specific guidelines for concurrent CLL and non-small cell lung carcinoma (NSCLC) treatment. Usually, when the tumors are diagnosed simultaneously, treatment is based to target the most aggressive malignancy, as the clinical outcomes depend on the response of the tumor with the poorest prognosis. For this reason, a multidisciplinary approach is mandatory. Case report: A patient with history of coronary heart disease, myocardial infarction and paroxysmal atrial fibrillation was diagnosed in 2019 (at the age of 71) with B chronic lymphocytic leukemia with bulky tumor (inguinal lymph nodes 8x5 cm), stage B according to Binet, intermediate risk. He was treated with 6 cycles of chemoimmunotherapy (rituximab/cyclofosfamid/fludarabine). In 10/2019 remission was confirmed, but MSCT described tumor in the posterior segment of upper right lung lobe measuring 20x17 mm and bilateral metastases up to 11 mm. Bronchoscopy and biopsy were performed, and EGFR neg, ALK neg, ROS 1 neg, PD-L1>50% adenocarcinoma was confirmed. He was referred to Clinical Hospital Center Osijek where monotherapy with pembrolizumab in a standard dose of 200 mg intravenously was started in 01/2020. Partial remission was confirmed in October 2020. Immunotherapy was discontinued due to development of pneumonitis, dysphagia and severe weight loss (20kg), but without radiologically confirmed disease progression. At that time he was referred to our hospital for further treatment. Gastroscopy has shown erosive gastritis with active duodenal ulcus, Forrest III. Supportive therapy and proton pump inhibitor were introduced. After complete regression of pneumonitis, improvement of general condition and resolution of dysphagia, no signs of lung cancer progression were found and pembrolizumab was reintroduced in 12/2021. Hypothyroidism was diagnosed in 01/2021 and levothyroxine replacement ther apy was started. In 03/2021 he underwent surgical removal of basal cell carcinoma of skin on the right temporal region with lobe reconstruction. From 02/2021, when pembrolizumab was reintroduced, regression in tumor size was continously confirmed with complete recovery of general condition. He was hospitalized for COVID 19 infection in 09/2021, and due to complications pembrolizumab was discontinued till 11/2021. Lung cancer immunotherapy proceeded till 11/2022, when Multidisciplinary team decided to finish pembrolizumab because of CLL relapse. CLL was in remission till August 2022 when due to B symptoms, lymphcytosis, anemia and generalized lymphadenopathy, hematological workup including biopsy of cervical lymph node was performed and CLL/SLL relapse was confirmed. Initially chlorambucil was introduced, but disease was refractory. Based on cytogenetic test results (IGHV unmutated, negative TP53) and due to cardiovascular comorbidity (contraindication for BTK inhibitors) venetoclax and rituximab were started in 01/2023. After just 1 cycle of treatment normal blood count as well as regression of B symptoms and peripheral lymphadenopathy occured, indicating the probability of complete disease remission. In our patient with metastatic lung adenocarcinoma excellent disease control is achieved during 41 month of treatment in first line setting. Furthermore, relapsed/refractory CLL/SLL is currently in confirmed remission. Conclusion(s): Successful treatment of patients with multiple primary malignancies is based on multidisciplinarity, early recognition and management of side effects, treatment of comorbidities with the aim of prolonging life, controlling symptoms of disease and preserving quality of life.

Lymphoproliferation- a clue towards an underlying monogenic disorder of immune dysregulation- a retrospective analysis from a single center in India

Background: Lymphoproliferation is the persistent proliferation of lymphoid cells and it's incidence in inborn errors of immunity varies from 0.7 to 18%. Material(s) and Method(s): This is a retrospective analysis of patients referred to the department of Immunology, B. J. Wadia Hospital for Children, Mumbai between March 2017 to December 2022. Inclusion criteria consisted of 3 months duration of significant lymphadenopathy and/or splenomegaly or history of lymphoma. The clinical characteristics, laboratory and molecular findings of the included patients were analyzed. Result(s): A total of 66 patients were included. There was a male preponderance with male:female ratio of 25:8. Median age of onset of lymphoproliferation was 4.75 years(Range 1 year to 60 years). Splenomegaly was seen in 75%. Infections included recurrent pneumonia (14/66), recurrent ear infections(5/66), COVID(4/66), one episode of pneumonia(6/66), herpes zoster(3/66), recurrent subcutaneous abscess (3/66), abdominal koch(3/66), chronic sinusitis(2/66), dermatophytosis(2/66), esophageal candidiasis(2/66), recurrent malaria(1/66), recurrent varicella(1/66), cryptococcal meningitis(1/66), gram negative sepsis(1/66), BCG adenitis(1/66), pseudomonas osteomyelitis(1/66), impetigo (1/66), pseudomonas urinary tract infection (1/66), chicken pox(1/66), herpes keratitis(1/66), dengue(1/66), Other manifestations included Evans plus phenotype(10/66), Evans phenotype(8/66), Autoimmune hemolytic anemia(5/66), bronchiectasis(5/66), Type 1 diabetes(3/66), hyper reactive airway disease(2/66), inflammatory bowel disease(4/66), autoimmune thrombocytopenia(2/66), stroke(3/66), hemophagocytic lymphohistiocytosis(2/66), hypertriglyceridemia(2/66), hypothyroidism(2/66), celiac disease(1/66), Type 2 diabetes(1/66), autoimmune encephalitis(1/66), autoimmune hepatitis(2/66), anti-parietal cell antibody(1/66), arthritis(1/66), autoimmune enteropathy(1/66), systemic lupus erythromatosus(1/66), primary biliary cirrhosis requiring liver transplant(1/66), nephrotic syndrome(1/66), lymphoedema(1/66), hypersplenism(1/66), recurrent oral ulcers(1/66), gout(1/66), dermatitis(1/66), ovarian teratoma(1/66), alopecia areata(1/66). Hodgkin's lymphoma(HL) was the most common malignancy(9/66), followed by non Hodgkin lymphoma(NHL)(6/66), transformation from NHL to HL(1/66), Burkitt to T-cell lymphoma(1/66), HL to DLBCL(1/66), HL to anaplastic T-cell lymphoma(1/66). EBV driven lymphoproliferation was seen in biopsy of21/66. Genetic testing showed mutations in LRBA(11/66), PIK3CD(5/66), CTLA4(3/66), TET2(2/66), IL2RA (1/66), IL12RB1(1/66), BACH2(1/66), PRKCD(1/66), TNFSFR13B(1/66), TNFAIP3(1/66), FAS(2/66), FASL(1/66), Caspase8(1/66), CARD11(1/66), RTEL1(1/66), AICD(1/66), PIK3R1(1/66), IKBKB(1/66). Treatment included IVIG, chemotherapy, rituximab, sirolimus, abatacept, HSCT. Conclusion(s): All children with persistent lymphoproliferation, with or without autoimmunity and/or infections should be worked up for an underlying monogenic disorder of immune dysregulation. Lymphomas presenting at abnormal site and/or age, relapse and EBV driven lymphomas require further evaluation. Presence of monogenic cause helps in providing targeted therapy.Copyright © 2023 Elsevier Inc.

Sequential Administration of SARS-CoV-2 Strains-Based Vaccines Effectively Induces Potent Immune Responses against Previously Unexposed Omicron Strain.

In the past few years, the continuous pandemic of COVID-19 caused by SARS-CoV-2 has placed a huge burden on public health. In order to effectively deal with the emergence of new SARS-CoV-2 variants, it becomes meaningful to further enhance the immune responses of individuals who have completed the first-generation vaccination. To understand whether sequential administration using different variant sequence-based inactivated vaccines could induce better immunity against the forthcoming variants, we tried five inactivated vaccine combinations in a mouse model and compared their immune responses. Our results showed that the sequential strategies have a significant advantage over homologous immunization by inducing robust antigen-specific T cell immune responses in the early stages of immunization. Furthermore, the three-dose vaccination strategies in our research elicited better neutralizing antibody responses against the BA.2 Omicron strain. These data provide scientific clues for finding the optimal strategy within the existing vaccine platform in generating cross-immunity against multiple variants including previously unexposed strains.

Immune Reconstitution and Vaccinations in Multiple Myeloma: A Report From the 19th International Myeloma Society Annual Workshop.

Given the significance of the immune system and the important role of therapies within the context of the immune system in plasma cell disorders, the International Myeloma Society annual workshop convened a session dedicated to this topic. A panel of experts covered various aspects of immune reconstitution and vaccination. The top oral presentations were highlighted and discussed. This is a report of the proceedings.

A Hepatitis B Virus Reactivation Case Potentially Triggered by the Onset of Diffuse Large B Cell Lymphoma.

An 81-year-old man underwent rituximab-containing chemotherapy for chronic lymphocytic leukemia (CLL). Thirteen years after his last chemotherapy, he was diagnosed with hepatitis B virus (HBV) reactivation. He was then treated with entecavir, and improvement was seen in his liver injury. He developed diffuse large B cell lymphoma (DLBCL) after improvement in his hepatitis. Despite chemotherapy, he contracted the coronavirus disease 2019 (COVID-19) and died of COVID-19. We suspect that HBV reactivation was triggered by DLBCL. When HBV reactivation occurs a long time after chemotherapy has concluded, the onset of DLBCL should be considered.

Idiotope-Driven T-Cell/B-Cell Collaboration-Based T-Cell Epitope Prediction Using B-Cell Receptor Repertoire Sequences in Infectious Diseases.

T-cell recognition of antigen epitopes is a crucial step for the induction of adaptive immune responses, and the identification of such T-cell epitopes is, therefore, important for understanding diverse immune responses and controlling T-cell immunity. A number of bioinformatic tools exist that predict T-cell epitopes; however, many of these methods highly rely on evaluating conventional peptide presentation by major histocompatibility complex (MHC) molecules, but they ignore epitope sequences recognized by T-cell receptor (TCR). Immunogenic determinant idiotopes are present on the variable regions of immunoglobulin molecules expressed on and secreted by B-cells. In idiotope-driven T-cell/B-cell collaboration, B-cells present the idiotopes on MHC molecules for recognition by idiotope-specific T-cells. According to the idiotype network theory formulated by Niels Jerne, such idiotopes found on anti-idiotypic antibodies exhibit molecular mimicry of antigens. Here, by combining these concepts and defining the patterns of TCR-recognized epitope motifs (TREMs), we developed a T-cell epitope prediction method that identifies T-cell epitopes derived from antigen proteins by analyzing B-cell receptor (BCR) sequences. This method allowed us to identify T-cell epitopes that contain the same TREM patterns between BCR and viral antigen sequences in two different infectious diseases caused by dengue virus and SARS-CoV-2 infection. The identified epitopes were among the T-cell epitopes detected in previous studies, and T-cell stimulatory immunogenicity was confirmed. Thus, our data support this method as a powerful tool for the discovery of T-cell epitopes from BCR sequences.

COVID-19 and reported mortality cases among rheumatic disease patients in Kuwait: Data from the Global Rheumatology Alliance registry.

Mycophenolate mofetil and rituximab have been shown to be considerably associated with poorer outcomes following SARS-CoV-2 infection. Such agents were associated with longer hospital stay as well as severe COVID-19 outcomes (infection-related complications, intensive care unit admission, and mortality). Using the data of the COVID-19 Global Rheumatology Alliance (GRA) registry of inflammatory rheumatic disease (IRD) patients in Kuwait, who had COVID-19 from March 2020 to March 2021, revealed 4 mortality cases (3 cases used CD-20 inhibitors as monotherapy and 1 case used mycophenolate mofetil/mycophenolic acid as monotherapy). This article describes the characteristics and course of disease among 4 patients with IRD who died following COVID-19 infection at Jaber Al Ahmed Hospital, Kuwait. The current series raises the intriguing prospect that IRD patients may have a varying risk of unfavorable clinical outcomes depending on the type of biological agents they were given. Rituximab and mycophenolate mofetil should be used with caution in IRD patients, particularly if they have concomitant comorbidities that put them at a high likelihood of developing severe COVID-19 outcomes.

A novel precision-serology assay for SARS-CoV-2 infection based on linear B-cell epitopes of Spike protein.

Introduction: The COVID-19 pandemic illustrates the need for serology diagnostics with improved accuracy. While conventional serology based on recognition of entire proteins or subunits thereof has made significant contribution to the antibody assessment space, it often suffers from sub-optimal specificity. Epitope-based, high-precision, serology assays hold potential to capture the high specificity and diversity of the immune system, hence circumventing the cross-reactivity with closely related microbial antigens. Methods: We herein report mapping of linear IgG and IgA antibody epitopes of the SARS-CoV-2 Spike (S) protein in samples from SARS-CoV-2 exposed individuals along with certified SARS-CoV-2 verification plasma samples using peptide arrays. Results: We identified 21 distinct linear epitopes. Importantly, we showed that pre-pandemic serum samples contain IgG antibodies reacting to the majority of protein S epitopes, most likely as a result of prior infection with seasonal coronaviruses. Only 4 of the identified SARS-CoV-2 protein S linear epitopes were specific for SARS-CoV-2 infection. These epitopes are located at positions 278-298 and 550-586, just proximal and distal to the RBD, as well as at position 1134-1156 in the HR2 subdomain and at 1248-1271 in the C-terminal subdomain of protein S. To substantiate the applicability of our findings, we tested three of the high-accuracy protein S epitopes in a Luminex assay, using a certified validation plasma sample set from SARS-CoV-2 infected individuals. The Luminex results were well aligned with the peptide array results, and correlated very well with in-house and commercial immune assays for RBD, S1 and S1/S2 domains of protein S. Conclusion: We present a comprehensive mapping of linear B-cell epitopes of SARS-CoV-2 protein S, that identifies peptides suitable for a precision serology assay devoid of cross-reactivity. These results have implications for development of highly specific serology test for exposure to SARS-CoV-2 and other members of the coronaviridae family, as well as for rapid development of serology tests for future emerging pandemic threats.

Infectious complications following CAR-t cell therapy for B cell non-Hodgkin lymphoma: a single-center experience and review of the literature.

Chimeric antigen receptor T-cell (CAR-T) therapy targeting CD19 has significantly improved outcomes in the treatment of refractory or relapsed (R/R) B-cell non-Hodgkin lymphoma (NHL). Several risk factors including CAR-T cell-related toxicities and their treatments often lead to infectious complications (ICs); however, the pattern and timeline is not well established. We evaluated ICs in 48 patients with R/R B-cell NHL following CAR-T cell therapy at our institution. Overall, 15 patients experienced 22 infection events. Eight infections (4 bacterial, 3 viral and 1 fungal) occurred within the first 30 days and 14 infections (7 bacterial, 6 viral, 1 fungal) between days 31 to 180 following CAR-T infusion. Most infections were mild-to-moderate and fifteen infections involved the respiratory tract. Two patients developed mild-to-moderate COVID-19 infection and one patient a cytomegalovirus reactivation after CAR-T infusion. Two patients developed IFIs: one case each of fatal disseminated candidiasis and invasive pulmonary aspergillosis at day 16 and 77, respectively. Patients with more than 4 prior antitumor regimens and patient's ≥ 65 years had a higher infection rate. Infections in patients with relapsed/refractory B-cell NHL are common after CAR-T despite the use of infection prophylaxis. Age ≥ 65 years and having > 4 prior antitumor treatments were identified as risk factors for infection. Fungal infections carried significant impact in morbidity and mortality, suggesting a role for increase fungal surveillance and/or anti-mold prophylaxis following high-dose steroids and tocilizumab. Four of ten patients developed an antibody response following two doses of SARS-CoV-2 mRNA vaccine.

Chapter 13 - The effect of COVID-19 on cancer immunotherapy and cancer care

: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), identified in Wuhan, China, in December 2019, rapidly spread globally to become a devastating global pandemic. The SARS-CoV-2 (coronavirus disease 2019 [COVID-19]) respiratory illness was initially reported in the United States in the state of Washington in January 2020. COVID-19 respiratory virus proved to be an extremely contagious illness with clinical features of fever, cough, dyspnea, malaise, and rapidly progressing severe interstitial pneumonia. Since the beginning of 2020, COVID-19 has been responsible for an unimagined level of deaths and socioeconomic disruption. The patient with malignancy and a suppressed immune system was, as expected, at increased risk for contracting COVID-19. Patients with cancer, when infected, had a more difficult clinical course and an increased rate of mortality. In the intervening 2+ years, much has been learned regarding the ability of the patient with cancer's immune system to not only fight the progression of their cancer but to effectively respond to newly available mRNA vaccines against COVID-19. As the pandemic continues, careful management of the vulnerable patient with cancer is essential.

Extrafollicular IgD-CD27-CXCR5-CD11c- DN3 B cells infiltrate inflamed tissues in autoimmune fibrosis and in severe COVID-19.

Although therapeutic B cell depletion dramatically resolves inflammation in many diseases in which antibodies appear not to play a central role, distinct extrafollicular pathogenic B cell subsets that accumulate in disease lesions have hitherto not been identified. The circulating immunoglobulin D (IgD)-CD27-CXCR5-CD11c+ DN2 B cell subset has been previously studied in some autoimmune diseases. A distinct IgD-CD27-CXCR5-CD11c- DN3 B cell subset accumulates in the blood both in IgG4-related disease, an autoimmune disease in which inflammation and fibrosis can be reversed by B cell depletion, and in severe COVID-19. These DN3 B cells prominently accumulate in the end organs of IgG4-related disease and in lung lesions in COVID-19, and double-negative B cells prominently cluster with CD4+ T cells in these lesions. Extrafollicular DN3 B cells may participate in tissue inflammation and fibrosis in autoimmune fibrotic diseases, as well as in COVID-19.

INTERIM RESULTS OF THE PML-16, PML-19 PROTOCOLS FOR PRIMARY MEDIASTINAL LARGE B-CELL LYMPHOMA THERAPY

Introduction. Primary mediastinal lymphoma (PML) is an aggressive lymphoid tumor treatment success of which is determined by induction therapy. To date, none of the standard chemotherapy regimens (CT) have demonstrated an advantage in efficacy. Intensive therapy programs are associated with high toxicity. Aim - to evaluate the efficacy and toxicity of two pilot prospective treatment protocols PML-16 and PML-19 as well as the possibility of using the analysis of freely circulating tumor DNA (ctDNA) to assess MRD in patients with PML. Materials and methods. From January 2016 to January 2022, 34 previously untreated PML patients were included in the study;average age - 32;stage > I - in 60 %;extramediastinal lesions - in 14.7 %;bulky disease - in 73.5 % of patients. Positron emission tomography combined with computed tomography (PET-CT) was performed;ctDNA was determined to assess the completeness of remission. Results. Eighteen patients received treatment according to the PML-16 protocol (6 courses of chemotherapy;2 blocks of RmNHL-BFM-90 + 4 courses of R-EPOCH). After the end of therapy, all 18 patients achieved PET-negative remission. The next 16 patients received treatment according to the PML-19 protocol (4 courses of chemotherapy;2 blocks of R-mNHL-BFM-90 + 2 courses of R-EPOCH) in combination with lenalidomide. After the end of therapy, 9 (56 %) patients achieved PET-negative remission;7 (44 %) retained pathological activity (D4-5 points). After 3 and 6 months 15 (94 %) patients achieved normalization of metabolic activity. Considering the high frequency of false-positive results in patients with PML, a ctDNA study was performed to determine the depth of remission in 15 patients. After the end of therapy, all 15 patients had complete elimination of ctDNA. Of these, 5 (33 %) remained PET-positive at the end of treatment. During further observation, after 3-6 months, in 4 patients the level of metabolic activity decreased to physiological without the use of consolidating therapy. After the end of therapy, one patient suffered the new coronavirus infection, COVID-19. A month later, residual formation of SUVmax 14.2 remained in the mediastinum. The patient is currently under observation. With a median follow-up of 36 months (9 to 76 months) all 34 patients are in remission. Conclusion. The effectiveness of PML-16 made it possible to abandon the consolidation therapy and refuted the idea of the need for 6 courses of CT. The combination of programs based on the application of the principle of high-dose short-pulse induction of remission (R-mNHL-BFM-90) in combination with the prolonged administration of medium doses (R-EPOCH) was crucial in achieving a successful result. The inclusion of lenalidomide in the "PML-19" program made it possible to achieve complete remission in 100 % of cases after 4 courses. The possibility of using DNA analysis to assess MRD in patients with PML was shown.Copyright © 2022 Izdatel'stvo Meditsina. All rights reserved.

A Diagnostically Challenging Case of Primary Pancreatic Lymphoma

Introduction: Primary Pancreatic Lymphoma (PPL) is the exceedingly rare instance of extranodal Non-Hodgkin's Lymphoma developing mainly in the pancreas.We report a diagnostically challenging case of a patient presenting with a rapidly growing pancreatic mass, found to have PPL. Case Description/Methods: A 48-year-old female with past history of tobacco use presented with several months of cramping abdominal pain following COVID-19 infection. She denied weight loss, fevers, or night sweats. Her physical exam, CBC, CMP, lipase, LDH, and CA 19-9 were unremarkable. An abdominal ultrasound revealed a 2.8 x 1.9 x 3 cm cystic mass of the pancreatic head, most congruent with a pseudocyst. Worsening abdominal pain prompted repeat ultrasound one month later, which showed a doubling in size. Endoscopic ultrasound (EUS) with fine needle aspiration of the cystic mass and surrounding lymph nodes yielded cystic contents and reactive lymphadenopathy. Two months later, her abdominal pain worsened and repeat imaging showed further doubling in size with encasement of the celiac plexus. A second FNA performed via EUS redemonstrated cystic contents. An ultrasound-guided core needle biopsy of the mass revealed necrotic CD301 diffuse large B cell lymphoma (DLBCL). PET scan was suggestive of stage IV PPL (Figure). Imaging also identified an inguinal lymph node that returned as CD101 BCL61 high grade follicular lymphoma, which was thought to be a distinct lesion. She was started on R-CHOP. Her clinical course was complicated by the formation and subsequent rupture of a splenic artery pseudoaneurysm, gastrointestinal bleeding, anuric kidney injury, and intestinal ischemia. She ultimately transitioned to comfort care. Discussion(s): Primary pancreatic lymphoma comprises 0.6% of extranodal lymphomas and 0.2% of primary pancreatic tumors. The clinical presentation is often vague and includes abdominal pain, B symptoms, jaundice, or bowel obstruction. The diagnostic criteria according to the WHO requires that the (1) majority of tumor burden be localized to the pancreas and (2) existing nearby and distant lymph node involvement should be secondary to pancreatic presentation. A biopsy is required to diagnose PPL, which is histologically most often DLBCL. Our case highlights the challenges associated with diagnosing PPL despite two EUS with FNA. Although rare, one should proceed with a high index of suspicion for PPL in any patient presenting with a rapidly enlarging pancreatic mass.

A Rare Cause of Enteritis in an Adult Male

Introduction: IgA vasculitis is more commonly seen in the pediatric population than in adults. Rarely IgA vasculitis is associated with malignancy, most commonly solid tumor malignancies, although there are case reports of association with hematologic malignancies. We report a case of large B-cell lymphoma mimicking IgA vasculitis in a 33-year-old immunosuppressed male with a prior history of IgA vasculitis. Case Description/Methods: A 33-year-old Caucasian male post renal transplant from reflux nephropathy on chronic immunosuppression was hospitalized for postprandial epigastric abdominal pain, nausea, vomiting and diarrhea. Two years prior, he was admitted for the same symptoms, palpable purpura of the lower extremities and elevated serum IgA. Enteroscopy had shown duodenal and jejunal ulceration with biopsies staining positive for IgA, confirming IgA vasculitis. He had complete resolution with a steroid taper. His current presentation had resulted in multiple hospital admissions, but empiric trial of steroids failed to alleviate symptoms. Vitals were normal and exam was notable for epigastric tenderness. Labs were notable for WBC 19.00 x103/cmm with normal differential, hemoglobin 9.2 gm/dL (prior 11.0 gm/dL), CRP 20.7 mg/L, serum creatinine 2.7 mg/dL (prior 1.5 mg/dL), and urinalysis with proteinuria, sterile pyuria, and hematuria. CTA abdomen/pelvis revealed thickening of the duodenum with shotty mesenteric lymph nodes without ischemia. Enteroscopy revealed an erythematous duodenum and jejunum (figure A). Jejunal biopsy (figure B) revealed CD20 positive cells consistent with DLCBL (figure C). He was seen by oncology and treated with R-CHOP but later unfortunately expired due to COVID-19 complications. Discussion(s): Non small cell lung cancer and renal cell carcinoma are most commonly associated with IgA vasculitis. It may also be seen in both Hodgkin and Non-Hodgkin lymphomas in adult patients. If IgA vasculitis occurs after a malignancy is diagnosed, it may indicate that metastasis has occurred. Malignancy associated IgA vasculitis is more likely to have an incomplete response to steroids and requires treatment of the underlying malignancy to achieve remission. Our case illustrates posterior probability error and premature closure cognitive biases. We should consider alternative diagnoses rather than anchor on prior diagnoses even when presentations are similar. Our case also highlights the importance of considering occult malignancy in adults with diagnosis of IgA vasculitis.

B-cell lymphoblastic lymphoma following intravenous BNT162b2 mRNA booster in a BALB/c mouse: A case report.

Unprecedented immunization campaigns have been rolled out worldwide in an attempt to contain the ongoing COVID-19 pandemic. Multiple vaccines were brought to the market, among two utilizing novel messenger ribonucleic acid technology. Despite their undisputed success in decreasing COVID-19-associated hospitalizations and mortality, various adverse events have been reported. The emergence of malignant lymphoma is one of such rare adverse events that has raised concern, although an understanding of the mechanisms potentially involved remains lacking. Herein, we present the first case of B-cell lymphoblastic lymphoma following intravenous high-dose mRNA COVID-19 vaccination (BNT162b2) in a BALB/c mouse. Two days following booster vaccination (i.e., 16 days after prime), at only 14 weeks of age, our animal suffered spontaneous death with marked organomegaly and diffuse malignant infiltration of multiple extranodal organs (heart, lung, liver, kidney, spleen) by lymphoid neoplasm. Immunohistochemical examination revealed organ sections positive for CD19, terminal deoxynucleotidyl transferase, and c-MYC, compatible with a B-cell lymphoblastic lymphoma immunophenotype. Our murine case adds to previous clinical reports on malignant lymphoma development following novel mRNA COVID-19 vaccination, although a demonstration of direct causality remains difficult. Extra vigilance is required, with conscientious reporting of similar cases and a further investigation of the mechanisms of action explaining the aforementioned association.

Antigen epitopes of animal coronaviruses: a mini-review.

Coronaviruses are widespread in nature and can infect mammals and poultry, making them a public health concern. Globally, prevention and control of emerging and re-emerging animal coronaviruses is a great challenge. The mechanisms of virus-mediated immune responses have important implications for research on virus prevention and control. The antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lymphocytes, playing an important role in antiviral immune responses. Thus, it can shed light on the development of diagnostic methods and novel vaccines. Here, we have reviewed advances in animal coronavirus antigenic epitope research, aiming to provide a reference for the prevention and control of animal and human coronaviruses. Supplementary Information: The online version contains supplementary material available at 10.1186/s44149-023-00080-0.

Sequential rituximab therapy sustains remission of nephrotic syndrome but carries high risk of adverse effects.

BACKGROUND: Sequential rituximab (RTX) administration has emerged as an important strategy to sustain remission of disease in patients with difficult-to-treat nephrotic syndrome. METHODS: We report the efficacy and safety of sequential therapy with two or more courses of intravenous RTX in 250 patients with difficult-to-treat steroid dependence (n = 127) and calcineurin inhibitor (CNI)-dependent or CNI-refractory steroid resistance (n = 123) managed at one center during 2015-2021. Subsets of patients were cross-sectionally tested for hypogammaglobulinemia, seroprotection against and hyporesponsiveness to vaccines for hepatitis B and tetanus, BK/JC viruria and human antichimeric antibodies (HACAs). RESULTS: Sequential RTX therapy, initiated at a median of 10 years [interquartile range (IQR) 7.3-14.4], was administered for 1.8 courses/person-year [95% confidence interval (CI) 1.7-2.0] over 2.0 years (95% CI 1.2-3.0). Therapy was associated with postponement of relapses by a median of 3 years in patients with steroid-sensitive disease and 2 years in those with steroid resistance. Relapses were reduced by a mean of 2.0 relapses/person-year (95% CI 1.8-2.2), enabling a reduction in prednisolone dose to 0.04 mg/kg/day (95% CI 0.01-0.11) and withdrawal of additional immunosuppression in 154 (62%) patients. RTX-associated adverse events, occurring at 0.20 events/person-year (95% CI 0.17-0.23), were chiefly comprised of infusion reactions (n = 108) and infections (n = 46); serious adverse events were observed in 10.8% patients, at 0.03 events/person-year (95% CI 0.02-0.05). Hypogammaglobulinemia was observed in 35% of 177 patients and was moderate to severe in 8.5% of cases. Rates of seroprotection at baseline and response following vaccination were lower for hepatitis B [1.9% and 29.4% (n = 52)] than tetanus [65.5% and 34.5% (n = 58)]. BK/JC viruria, without viremia, was observed in 7.3% of 109 cases. A total of 19 of 107 patients (17.8%) had HACAs, which were associated with B cell nondepletion and serum sickness. Age at therapy of <9-10 years was associated with a risk of early relapse, treatment failure and hypogammaglobulinemia following RTX therapy. CONCLUSIONS: Sequential therapy with RTX effectively reduces relapses in patients with difficult-to-treat steroid- and/or CNI-dependent or CNI-refractory nephrotic syndrome. Therapy is associated with high rates of hypogammaglobulinemia and infusion reactions.

COVID-19 vaccination-related [18F]FDG-avid lymph node in a patient with marginal zone B-cell lymphoma

The [18F]FDG PET/CT is a crucial tool in the diagnostic process and monitoring of neoplastic diseases. Currently, during the global program of vaccination against COVID-19 and the possibility of axillary lymphadenopathy after this injection, the correct interpretation of PET/CT images is vitally significant and may create some difficulties. We present a case of increased uptake of [18F]FDG in an axillary lymph node in a PET/CT scan performed 2 days after the Pfizer BioNTech COVID-19 vaccine in a 48-year-old patient newly diagnosed with marginal zone B-cell lymphoma.Copyright © 2023 Via Medica.