Increased B-cell activity with consumption of activated monocytes in severe COVID-19 patients

The characterization of CD8+ T-cell responses in COVID-19

This review gives an overview of the protective role of CD8+ T cells in SARS-CoV-2 infection. The cross-reactive responses intermediated by CD8+ T cells in unexposed cohorts are described. Additionally, the relevance of resident CD8+ T cells in the upper and lower airway during infection and CD8+ T-cell responses following vaccination are discussed, including recent worrisome breakthrough infections and variants of concerns (VOCs). Lastly, we explain the correlation between CD8+ T cells and COVID-19 severity. This review aids in a deeper comprehension of the association between CD8+ T cells and SARS-CoV-2 and broadens a vision for future exploration.

Adaptive humoral immune response and cellular immune status in cancer patients and patients under immunosuppression vaccinated against SARS-CoV-2

BACKGROUND

Patients with cancer and autoimmune diseases are at higher risk of severe COVID-19. They may not develop protective immune responses following vaccination. We investigated patients' cellular and humoral immune response after two COVID-19 vaccine doses.

RESEARCH DESIGN AND METHODS

Subjects were stratified into subgroups according to therapy and grade of immunosuppression at time of vaccination.

RESULTS

Antibody titers were compared to healthy controls. 32/122 (26%) did not develop detectable antibody titers. Of these, 22 (66.6%) had active therapy. Patients showed significant lower antibody titers compared to controls (median 790 vs. 3923 AU/mL, p = 0.026). Patients with active therapy had significant lower antibody titers compared to those without (median 302 vs. 3952 U/L P < 0.001). B-cell count was lower in the group without antibody titers (median 29.97 vs. 152.8; p = 0.002). 100% of patients under anti-CD20 therapy had no detectable antibody titer, followed by anti-TNF (66%), BTK inhibitors (50%), ruxolitinib (35.5%), TKI (14.2%), and lenalidomide (12.5%). Anti-CD20 therapy, ruxolitinib, BTK inhibitors, and anti-CD38 therapy presented significant lower antibody titers compared to controls.

CONCLUSIONS

Patients undergoing therapy for cancer or autoimmune diseases are at higher risk of insufficient humoral immune response following COVID-19 vaccination. Furthermore, alterations in the B-cell compartment correlate with lower antibody titers.

Reduction in Chest CT Severity and Improved Hospital Outcomes in SARS-CoV-2 Omicron Compared with Delta Variant Infection

Background The SARS-Cov-2 Omicron variant demonstrates rapid spread but reduced disease severity. Studies evaluating lung imaging findings of Omicron infection versus non-Omicron infection remain lacking. Purpose To compare the Omicron variant with the SARS-CoV-2 Delta variant according to their chest CT radiologic pattern, biochemical parameters, clinical severity, and hospital outcomes after adjusting for vaccination status. Materials and Methods This retrospective study included hospitalized adult patients with reverse transcriptase-polymerase chain reaction test results positive for SARS-CoV-2, with CT pulmonary angiography performed within 7 days of admission between December 1, 2021, and January 14, 2022. Multiple readers performed blinded radiologic analyses that included RSNA CT classification, chest CT severity score (CTSS) (range, 0 [least severe] to 25 [most severe]), and CT imaging features, including bronchial wall thickening. Results A total of 106 patients (Delta group, n = 66; Omicron group, n = 40) were evaluated (overall mean age, 58 years ± 18 [SD]; 58 men). In the Omicron group, 37% of CT pulmonary angiograms (15 of 40 patients) were categorized as normal compared with 15% (10 of 66 patients) of angiograms in the Delta group (P = .016). A generalized linear model was used to control for confounding variables, including vaccination status, and Omicron infection was associated with a CTSS that was 7.2 points lower than that associated with Delta infection (β = -7.2; 95% CI: -9.9, -4.5; P < .001). Bronchial wall thickening was more common with Omicron infection than with Delta infection (odds ratio [OR], 2.4; 95% CI: 1.01, 5.92; P = .04). A booster shot was associated with a protective effect for chest infection (median CTSS, 5; IQR, 0-11) when compared with unvaccinated individuals (median CTSS, 11; IQR, 7.5-14.0) (P = .03). The Delta variant was associated with a higher OR of severe disease (OR, 4.6; 95% CI: 1.2, 26; P = .01) and admission to a critical care unit (OR, 7.0; 95% CI: 1.5, 66; P = .004) when compared with the Omicron variant. Conclusion The SARS-CoV-2 Omicron variant was associated with fewer and less severe changes on chest CT images compared with the Delta variant. Patients with Omicron infection had greater frequency of bronchial wall thickening but less severe disease and improved hospital outcomes when compared with patients with Delta infection. © RSNA, 2022 Online supplemental material is available for this article.

C-reactive protein Lymphocyte Ratio in the Diagnosis of Pulmonary Tuberculosis

Background: Tuberculosis (TB) is still a severe problem in underdeveloped and developing countries. Diagnostic tests are unavailable in every health institution, and TB culture can take up to 45 days. Therefore, there is a need for cheaper, faster, and easily accessible diagnostic methods that can guide the diagnosis. This study aimed to determine whether red blood cell distribution width (RDW), C-reactive protein (CRP)-lymphocyte ratio (CLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR) can be used as biomarkers in the diagnosis of pulmonary TB in patients with no comorbidities. Material and Methods: Files of microbiologically confirmed 122 patients with pulmonary TB and 153 patients in whom pulmonary TB was excluded were retrospectively reviewed. Out of them, patients with comorbidities were excluded from the study. Eighty-one patients with TB and 100 controls were included in the study. Results: The lymphocyte, eosinophil, and LMR levels remained significantly lower in the TB group, while neutrophil, monocyte, RDW, platelet, and PLR levels were higher in the same group. Conclusion: In those patients suspicious of pulmonary TB, higher levels of RDW, PLR, and CLR, whereas lower levels of eosinophil, PDW, and LMR may predict the diagnosis of pulmonary TB in previously healthy individuals.

Eosinophil Levels, Neutrophil-Lymphocyte Ratio, and Platelet-Lymphocyte Ratio in the Cytokine Storm Period of Patients with COVID-19

BACKGROUND

In the early stages of the COVID-19 pandemic, elevated inflammatory cytokine levels, particularly interleukin-6 (IL-6), were detected in patients with cytokine storm (CS).

AIMS

This study aimed to investigate levels, diagnostic usefulness, and optimal cutoff values of monocyte, eosinophil, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) in CS of patients with COVID-19 and also to identify risk factors for mortality.

METHODS

Seventy-six patients with COVID-19 who developed CS and randomly chosen 150 COVID-19 patients who had no CS during their stay in the hospital were included in the study.

RESULTS

Lymphocytes and eosinophil levels remained lower in the CS group. Patients with low lymphocyte levels had a higher risk for mortality (OR: 1.92). Neutrophil, D-dimer, ferritin, IL-6, NLR, and PLR were higher in the CS group. High levels of neutrophil, ferritin, D-dimer, and NLR and a history of coronary artery disease (CAD) and diabetes mellitus (DM) were identified as independent risk factors for mortality.

CONCLUSION

In the light of the obtained results, COVID-19 patients with a decrease in lymphocyte levels and an increase in NLR and D-dimer levels and a history of CAD and DM have a higher risk of cytokine storm and mortality.

Immunopathology and Immunosenescence, the Immunological Key Words of Severe COVID-19. Is There a Role for Stem Cell Transplantation?

The outcomes of Coronavirus disease-2019 (COVID-19) vary depending on the age, health status and sex of an individual, ranging from asymptomatic to lethal. From an immunologic viewpoint, the final severe lung damage observed in COVID-19 should be caused by cytokine storm, driven mainly by interleukin-6 and other pro-inflammatory cytokines. However, which immunopathogenic status precedes this "cytokine storm" and why the male older population is more severely affected, are currently unanswered questions. The aging of the immune system, i.e., immunosenescence, closely associated with a low-grade inflammatory status called "inflammageing," should play a key role. The remodeling of both innate and adaptive immune response observed with aging can partly explain the age gradient in severity and mortality of COVID-19. This review discusses how aging impacts the immune response to the virus, focusing on possible strategies to rejuvenate the immune system with stem cell-based therapies. Indeed, due to immunomodulatory and anti-inflammatory properties, multipotent mesenchymal stem cells (MSCs) are a worth-considering option against COVID-19 adverse outcomes.