Mucosa-Associated Lymphoid Tissue Lymphoma of the Rectum Incidentally Found in a Patient with Ulcerative Colitis

Introduction: Mucosa-associated lymphoid tissue (MALT) lymphomas are extra-nodal marginal zone B-cell lymphomas, most commonly found in the stomach, associated with Helicobacter pylori infections, and generally not linked with inflammatory bowel disease. Rectal MALT lymphoma is very uncommon and often associated with painful defecation, change in bowel habits, or rectal pressure/prolapse. Here, we present a rare case of an asymptomatic female with ulcerative colitis (UC) found to have benign-appearing rectal polyps during a routine screening colonoscopy. Case Description/Methods: The patient is a 56-year-old female with a history of left-sided UC, diagnosed in 1993, with one flare after receiving the 2nd dose of the Moderna COVID-19 vaccine, taking oral Olsalazine 500 mg twice daily, low-dose Prednisone, and mesalamine suppositories as needed presenting for screening colonoscopy. The patient was asymptomatic, citing regular non-bloody bowel movements and normal stool consistency. Colonoscopy revealed two 7 mm sessile, non-bleeding rectal polyps, surrounded by congested, erythematous, friable, and ulcerated mucosa in the rectosigmoid colon. Cold forceps biopsies were taken. Hematopathology evaluation of the routine colon biopsy samples revealed chronic nonspecific colitis while pathology of the rectal polyps showed marked lymphoplasmacytic infiltrate and extra-nodal marginal zone lymphoma of MALT. Ancillary studies, immunohistochemistry, and molecular studies for B-cell gene rearrangement confirmed extra-nodal marginal zone lymphoma of MALT with prominent plasmacytic differentiation. The patient was informed and close follow-up in Gastroenterology clinic was arranged. (Figure) Discussion: Rectal MALT lymphoma is rare with unclear management options. Treatments of UC include watchful waiting, surgical resection, endoscopic mucosal resection, radiation, and/or chemotherapy. Helicobacter pylori infections, though strongly linked with gastric MALT lymphoma, have not been shown to be strongly correlated with rectal MALT lymphoma. Given that patients with UC have chronic UCassociated colonic inflammation, lymphoma is often difficult to distinguish visually during colonoscopy, frequently masked by ulcerations and pseudo-polyps. In cases like these, more definitive treatments such as surgical resection could therefore be warranted. Long-term follow-up data is sparse and definitive management remains a clinical conundrum, thus these patients require reliable long-term multidisciplinary close follow-up. (Figure Presented).

Adaptive Immunity Dysregulation Is Associated to the Development of Long Covid

Background: The pathogenetic mechanisms behind the development of long- COVID (LC) are largely unknown. Because both plasma SARS-CoV-2 RNAemia and dysregulated immunity have been correlated with COVID-19 severity, we evaluated whether they are associated with LC. Method(s): We consecutively enrolled unvaccinated hospitalized COVID-19 patients during acute-COVID-19 (T0) in March-October 2020 who either developed LC at a follow-up visit 2-3 months from virologic clearance (T1) or did not. LC was defined as persistence >=2 months after recovery of >=1 symptom: anosmia, dysgeusia, fever, gastrointestinal symptoms, dyspnoea, fatigue, musculoskeletal pain, muscle weakness, brain fog. We measured: SARS-CoV-2 RNAemia (RT-qPCR, log10(copies/mL)), magnitude (ELISA, AUC) and functionality (pseudovirus neutralization, ID50;Fc-mediated functions, %ADCC) of SARS-CoV-2-specific antibodies, SARS-CoV-2-specific B and CD4-T-cells (Immunophenotype, AIM and ICS assays). Result(s): We enrolled 48 COVID-19 individuals, 38/48 (79.2%) developed LC (LC+) and 10 did not (LC-). LC+ and LC- had similar co-morbidities and symptoms in the acute phase (Fig.1A), and the majority showed a radiologically documented SARS-CoV-2 pneumonia. The SARS-CoV-2 RNAemia did not differ between groups at both time points. The levels of RBD-specific Abs, as well as their functionality, appeared to increase over time in the LC- group but not in the LC+ (Fig.1B-D). Similarly, a trend towards increased RBD-specific B-cells was observed over time in the LC- group but not in LC+ (Fig.1E). B-cell immunophenotyping showed a significant increase over time of classical memory B cells (MBCs) at the expenses of activated MBCs (Fig.1F-G) as well as an IgA class-switching in the LC- group compared to LC+ (Fig.1H-I). Furthermore, LC+ showed a faster decline of SARS-CoV-2-specific (CD69+CD137+) CD4- TEMRA and CD4-TEM (Fig.1L-M). Finally, IFN-gamma-producing TREG of LC- individuals increased over time (Fig.1N). Conclusion(s): Acutely ill, hospitalized COVID-19 patients developing LC feature a dysregulated SARS-CoV-2-specific humoral as well as B- and T-cell response, in both magnitude and functionality, suggesting a link between dysregulated SARS-CoV-2-specific adaptive immunity and LC development. The fine understanding of the factors contributing to such dysregulation in LC patients is strongly needed, that might further inform targeted therapeutic interventions. (Figure Presented).

Patients with B-cell malignancies experience reduced antibody responses with class switching defect following BNT162b2 SARS-CoV-2 vaccination

Vaccines having aided in escaping the majority of the population from immunological naïvety, our strategies are now shifting towards an increased focus on identifying and protecting the extremely vulnerable. We here describe the results of testing 12 patients, those with lymphoid malignancies having been targeted their B-cells for therapy with rituximab-containing regimens or a Bruton tyrosine kinase inhibitor, for anti-SARS-CoV-2 spike antibodies after receiving the BNT162b2 mRNA vaccine doses. The interval from last dosing of B-cell depletion therapy to SARS-CoV-2 vaccination was at median 5.3 (range 3.1–6.6) months. Using the ‘seroprotection' threshold of 775 [BAU/mL] for the anti-spike antibody titer, our finding points out the crucial unresponsiveness of the targeted population with 0/12 (0%) achieving ‘seroprotection'. Although IgG seroconversion was observed in 4/12 (33%), supporting the overall benefit of vaccination, the figures still point out a potential need for optimization of practice. IgA was further less responsive (unsuccessful ‘seroconversion' in 11/12 (92%)), implicating an underlying class switch defect. Those with depletion on B-cells are caught at a dilemma between, being too early and too late on receiving SARS-CoV-2 vaccines. They wish to get over their immunological naïvety at the earliest, while, in order to assure quality immune memory, are also required to hold the patience for their B-cells to repopulate. Although it remains an issue whether intensified vaccine schedules and/or regimens will lead to stronger immunogenicity or more effective boosters for non-responders, we shall take advantage of every increasing evidence in order to optimize current options. © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases

COVID-19 vaccine responsiveness in patients with multiple myeloma and waldenström macroglobulinemia

BACKGROUND: Multiple myeloma (MM) and Waldenström macroglobulinemia (WM) are associated with significant immunoparesis. Based on the ongoing COVID-19 pandemic, there is an urgent need to understand whether patients are able to mount a sufficient response to COVID-19 vaccines. METHODS: MM and WM patients are vaccinated with mRNA-1273 (Moderna), BNT162b2 mRNA (Pfizer/BioNTech), or JNJ-78436735 (Johnson & Johnson) in a prospective clinical trial. Primary endpoint is SARS-CoV-2 spike protein (S) antibody (Ab) detection 28 days after final vaccination. Secondary endpoints include functional serologic assessments and T-cell responses at 28 days, 6 months, 9 months, and 12 months following vaccination. S Abs were detected by Elecsys assay (Roche Diagnostics), with 3 0.80 U/mL defined as positive and titers > 250 U/mL considered stronger correlates of neutralization. SARS-CoV-2 wildtype and variant S-specific Ab isotypes and FcγR binding profiles were quantified by custom Luminex assay. Antibody-dependent neutrophil and cellular phagocytosis (ADNP and ADCP) were assessed using flow cytometry. RESULTS: To date 141 patients have been enrolled, 137 (91 MM and 46 WM) of whom had an S Ab assessment. Median Ab titer was 178.0 (IQR, 16.10-1166.0) for MM and 3.92 (IQR, 0-278.9) for WM. S Ab response rate was 91% (83/91) in MM and 56% (27/46) in WM. However, responses achieving S Ab >250 U/mL were 47.3% (43/91) in MM and 26.1% (12/46) in WM. In patients 375 years, responses >250 u/mL were 13.3% (2/15;p<0.05). Vaccine-specific S Ab responses >250 u/mL following mRNA-1273, BNT162b2, and JNJ-78436735 were 67.6% (23/34;p<0.05), 38.3% (18/47;p=NS), and 20% (2/10;p=NS) in MM and 50.0% (8/16;p<0.05), 14.8% (4/27;p<0.05), and 0% (0/3;p=NS) in WM. Among MM patients with progressive disease, S Ab response >250 u/mL occurred in 30% (6/20) as opposed to 55.6% (30/54) for VGPR+ (p<0.05). MM patients having autologous stem cell transplant within 12 months demonstrated 100% (5/5;p<0.05) S Ab responses. For MM patients actively receiving an anti-CD38 monoclonal Ab or an immunomodulatory drug, S Ab response occurred in 38.9% (14/36;p=NS) and 50.9% (28/55;p<0.05). Among WM patients, S Ab responses >250 U/mL occurred in 63.6% (7/11;p<0.05) previously untreated;0% (0/9;p<0.05) who received rituximab within 12 months;10% (2/20);p<0.05) on an active Bruton Tyrosine Kinase (BTK) inhibitor;and 20% (3/15;p=NS) who received other therapies. Functional Ab studies were performed on 14 MM patients, 14 WM, patients, and 14 healthy donors (HD) (Figure 1). All patients were assessed 28 days following their final vaccination and myeloma patients had an additional assessment 28 days following initial vaccination. MM and WM patients demonstrated less IGG1 and IGG3 S Ab production than HD. MM patients showed increased IgA and IgM S Ab production as well as increased FcgR2A binding following a second vaccine in contrast to HD. Both ADNP and ADCP were reduced in MM and WM patients. MM patients demonstrated improved ADCP in SARS-CoV-2 variants B.1.351, B.1.117, and P.1 versus wildtype (p<0.05). CONCLUSIONS: We report the first known evidence of impaired functional humoral responses following COVID-19 vaccines in patients with MM and WM. Overall, WM patients showed more severe impairment of COVID-19 S Ab responses. Most previously untreated WM patients achieved S Ab responses, however the most significant reduction in S Ab responses were seen in WM patients who received rituximab within 12 months or active BTK inhibitors. For MM patients, being in disease remission associated with improved S Ab response. Among MM and WM patients, age 375 years associated with significantly lower rates and vaccination with MRNA-1273 (Moderna) elicited significantly higher S Ab response rates than other vaccines. A defect in ADNP and more profound defect in ADCP suggests overall compromised opsinophagocytic activity among MM and WM patients. Data comparing first and second vaccine responses in MM patients, suggest less efficient class switching to IGG as well as incomple e maturation of their FcgR2A binding profiles but normal maturation of FcgR3A. Interestingly, ADCP was improved in several emerging SARS-CoV-2 variants. T-cell studies are pending and will be updated. Further understanding of the immunological response to COVID19 vaccination is needed to clarify patients risks, and necessity for booster or alternative protective measures against COVID-19. (Figure Presented).