Predictors of poor seroconversion and adverse events to SARS-CoV-2 mRNA BNT162b2 vaccine in cancer patients on active treatment.

PURPOSE: Initial findings in patients with cancer suggest a lower seroconversion to SARS-CoV-2 vaccination possibly related to myelo-immunosuppressive therapies. We conducted a prospective study to assess factors predicting poor seroconversion and adverse events following immunisation (AEFI) to the BNT162b2 vaccine in patients on active treatment. PATIENTS AND METHODS: Cancer patients, candidates to two doses of BNT162b2 SARS-CoV-2 vaccination, were enrolled. Patients on active surveillance served as controls. The primary endpoint was poor seroconversion (anti S1/S2 IgG < 25 AU/mL) after 21 days from the second dose. RESULTS: Between March and July 2021, 320 subjects were recruited, and 291 were assessable. The lack of seroconversion at 21 days from the second dose was 1.6% (95% CI, 0.4-8.7) on active surveillance, 13.9% (8.2-21.6) on chemotherapy, 11.4% (5.1-21.3) on hormone therapy, 21.7% (7.5-43.7) on targeted therapy and 4.8% (0.12-23.8) on immune-checkpoint-inhibitors (ICI). Compared to controls, the risk of no IgG response was greater for chemotherapy (p = 0.033), targeted therapy (0.005) and hormonotherapy (p = 0.051). Lymphocyte count < 1 × 109/L (p = 0.04) and older age (p = 0.03) also significantly predicted poor seroconversion. Overall, 43 patients (14.8%) complained of AEFI, mostly of mild grade. Risk of AEFI was greater in females (p = 0.001) and younger patients (p = 0.009). CONCLUSION: Chemotherapy, targeted therapy, hormone therapy, lymphocyte count < 1 × 109/L, and increasing age predict poor seroconversion after two doses of BNT162b2 in up to 20% of patients, indicating the need for a third dose and long-term serological testing in non-responders. AEFI occur much more frequently in women and younger subjects who may benefit from preventive medications. CLINICALTRIALS. GOV IDENTIFIER: NCT04932863.

Case Report: A Peculiar Case of Inflammatory Colitis After SARS-CoV-2 Infection

We report a case of inflammatory colitis after SARS-CoV-2 infection in a patient with no additional co-morbidity who died within three weeks of hospitalization. As it is becoming increasingly clear that SARS-CoV-2 infection can cause immunological alterations, we investigated the expression of the inhibitory checkpoint PD-1 and its ligand PD-L1 to explore the potential role of this axis in the break of self-tolerance. The presence of the SARS-CoV-2 virus in colon tissue was demonstrated by qRT-PCR and immunohistochemical localization of the nucleocapsid protein. Expression of lymphocyte markers, PD-1, and PD-L1 in colon tissue was investigated by IHC. SARS-CoV-2-immunoreactive cells were detected both in the ulcerated and non-ulcerated mucosal areas. Compared to healthy tissue, where PD-1 is weakly expressed and PD-L1 is absent, PD-1 and PD-L1 expression appears in the inflamed mucosal tissue, as expected, but was mainly confined to non-ulcerative areas. At the same time, these markers were virtually undetectable in areas of mucosal ulceration. Our data show an alteration of the PD-1/PD-L1 axis and suggest a link between SARS-CoV-2 infection and an aberrant autoinflammatory response due to concomitant breakdown of the PD-1/PD-L1 interaction leading to early death of the patient.

Untimely TGFß responses in COVID-19 limit antiviral functions of NK cells.

SARS-CoV-2 is a single-stranded RNA virus that causes COVID-19. Given its acute and often self-limiting course, it is likely that components of the innate immune system play a central part in controlling virus replication and determining clinical outcome. Natural killer (NK) cells are innate lymphocytes with notable activity against a broad range of viruses, including RNA viruses1,2. NK cell function may be altered during COVID-19 despite increased representation of NK cells with an activated and adaptive phenotype3,4. Here we show that a decline in viral load in COVID-19 correlates with NK cell status and that NK cells can control SARS-CoV-2 replication by recognizing infected target cells. In severe COVID-19, NK cells show defects in virus control, cytokine production and cell-mediated cytotoxicity despite high expression of cytotoxic effector molecules. Single-cell RNA sequencing of NK cells over the time course of the COVID-19 disease spectrum reveals a distinct gene expression signature. Transcriptional networks of interferon-driven NK cell activation are superimposed by a dominant transforming growth factor-ß (TGFß) response signature, with reduced expression of genes related to cell-cell adhesion, granule exocytosis and cell-mediated cytotoxicity. In severe COVID-19, serum levels of TGFß peak during the first two weeks of infection, and serum obtained from these patients severely inhibits NK cell function in a TGFß-dependent manner. Our data reveal that an untimely production of TGFß is a hallmark of severe COVID-19 and may inhibit NK cell function and early control of the virus.

Teaching histology and anatomy online during the COVID-19 pandemic.

The aim of this study is to analyze differences in participation, and in the results obtained in the anatomy and histology exams, over two academic years of the Sport Sciences degree course. During the first semester of the academic year 2019/2020 both the lectures and the exam took place face-to-face, while during the academic year 2020/2021 everything was done online. Statistical analysis revealed that the online modality was especially advantageous for the anatomy exam. Students' opinions were also assessed through a short questionnaire. The results showed that teachers involved themselves in both groups. Students needed to interact socially with teachers and colleagues and to ask them questions. Even if the differences were not significant, the difference was greater for face-to-face students in most comparisons. Finally, the most common methods of peer communication were by social media.