Quality of T-Cell Response to SARS-CoV-2 mRNA Vaccine in ART-Treated PLWH.

We investigated specific humoral and T-cell responses in people living with HIV (PLWH) before (T0), after two (T1) and after six months (T2) from the third dose of the BNT162b2 vaccine. Healthy donors (HD) were enrolled. The specific humoral response was present in most PLWH already after the second dose, but the third dose increased both the rate of response and its magnitude. Collectively, no significant differences were found in the percentage of responding T-cells between PLWH and HD. At T0, stratifying PLWH according to CD4 cell count, a lower percentage of responding T-cells in <200 cells/µL subgroup compared to >200 cells/µL one was observed. At T1, this parameter was comparable between the two subgroups, and the same result was found at T2. However, the pattern of co-expression of IFNγ, IL2 and TNFα in PLWH was characterized by a higher expression of TNFα, independently of CD4 cell count, indicating a persistent immunological signature despite successful ART. mRNA vaccination elicited a specific response in most PLWH, although the cellular one seems qualitatively inferior compared to HD. Therefore, an understanding of the T-cell quality dynamic is needed to determine the best vaccination strategy and, in general, the capability of immune response in ART-treated PLWH.

Major reduction of NKT cells in patients with severe COVID-19 pneumonia.

BACKGROUND: NK cells seem to be mainly involved in COVID-19 pneumonia. Little is known about NKT cells which represent a bridge between innate and adaptive immunity. METHODS: We characterized peripheral blood T, NK and NKT cells in 45 patients with COVID-19 pneumonia (COVID-19 subjects) and 19 healthy donors (HDs). According to the severity of the disease, we stratified COVID-19 subjects into severe and non-severe groups. RESULTS: Compared to HDs, COVID-19 subjects showed higher percentages of NK CD57+ and CD56dim NK cells and lower percentages of NKT and CD56bright cells. In the severe group we found a significantly lower percentage of NKT cells. In a multiple logistic regression analysis, NKT cell was independently associated with the severity of the disease. CONCLUSIONS: The low percentage of NKT cells in peripheral blood of COVID-19 subjects and the independent association with the severity of the disease suggests a potential role of this subset.

JCPyV NCCR analysis in PML patients with different risk factors: exploring common rearrangements as essential changes for neuropathogenesis.

BACKGROUND: During severe immunosuppression or treatment with specific biological drugs, human polyomavirus JC (JCPyV) may establish a lytic infection in oligodendrocytes, leading to progressive multifocal leukoencephalopathy (PML). Beyond AIDS, which represents the most common predisposing condition, several biological drugs have been associated to the development of PML, such as natalizumab, fingolimod and dimethyl fumarate, which have been showed to increase the risk of PML in the multiple sclerosis (MS) population. JCPyV non-coding control region (NCCR) can be found in two different forms: a virulent neurotropic pathogenic form and a latent non-pathogenic form. The neurotropic forms contain a rearranged NCCR and are typically found in the cerebrospinal fluid, brain or blood of PML patients. CASE PRESENTATION: We sequenced and critically examined JCPyV NCCR from isolates detected in the cerebrospinal fluid of four newly diagnosed progressive multifocal leukoencephalopathy patients: two HIV-positive and two HIV-negative multiple sclerosis patients. More complex NCCR rearrangements were observed in the two HIV-positive patients compared to the HIV-negative multiple sclerosis patients with PML. CONCLUSIONS: The comparison of HIV-positive and HIV-negative MS patients with PML, allowed us to evidence the presence of a common pattern of JCPyV NCCR rearrangement, characterized by the deletion of the D-block, which could be one of the initial rearrangements of JCPyV NCCR needed for the development of PML.

Chest CT score in COVID-19 patients: correlation with disease severity and short-term prognosis.

OBJECTIVES: To correlate a CT-based semi-quantitative score of pulmonary involvement in COVID-19 pneumonia with clinical staging of disease and laboratory findings. We also aimed to investigate whether CT findings may be predictive of patients' outcome. METHODS: From March 6 to March 22, 2020, 130 symptomatic SARS-CoV-2 patients were enrolled for this single-center analysis and chest CT examinations were retrospectively evaluated. A semi-quantitative CT score was calculated based on the extent of lobar involvement (0:0%; 1, < 5%; 2:5-25%; 3:26-50%; 4:51-75%; 5, > 75%; range 0-5; global score 0-25). Data were matched with clinical stages and laboratory findings. Survival curves and univariate and multivariate analyses were performed to evaluate the role of CT score as a predictor of patients' outcome. RESULTS: Ground glass opacities were predominant in early-phase (≤ 7 days since symptoms' onset), while crazy-paving pattern, consolidation, and fibrosis characterized late-phase disease (> 7 days). CT score was significantly higher in critical and severe than in mild stage (p < 0.0001), and among late-phase than early-phase patients (p < 0.0001). CT score was significantly correlated with CRP (p < 0.0001, r = 0.6204) and D-dimer (p < 0.0001, r = 0.6625) levels. A CT score of ≥ 18 was associated with an increased mortality risk and was found to be predictive of death both in univariate (HR, 8.33; 95% CI, 3.19-21.73; p < 0.0001) and multivariate analysis (HR, 3.74; 95% CI, 1.10-12.77; p = 0.0348). CONCLUSIONS: Our preliminary data suggest the potential role of CT score for predicting the outcome of SARS-CoV-2 patients. CT score is highly correlated with laboratory findings and disease severity and might be beneficial to speed-up diagnostic workflow in symptomatic cases. KEY POINTS: • CT score is positively correlated with age, inflammatory biomarkers, severity of clinical categories, and disease phases. • A CT score ≥ 18 has shown to be highly predictive of patient's mortality in short-term follow-up. • Our multivariate analysis demonstrated that CT parenchymal assessment may more accurately reflect short-term outcome, providing a direct visualization of anatomic injury compared with non-specific inflammatory biomarkers.

Fecal Microbial Transplantation impact on gut microbiota composition and metabolome, microbial translocation and T-lymphocyte immune activation in recurrent Clostridium difficile infection patients.

This short communication reports the preliminary results of Fecal Microbial Transplantation (FMT) impact on microbiota, microbial translocation (MT), and immune activation in four recurrent Clostridium difficile infection (R-CDI) patients. After FMT a restore of gut microbiota composition with a significant increase of fecal acetyl-putrescine and spermidine and fecal acetate and butyrate, a decrease of immune activation of T cells CD4+ and CD8+levels, and of LPS binding protein (LBP) level, were observed. Preliminary results indicate that FMT seems to be helpful not only as a CDI radical cure, with an impact on fecal microbiota and metabolome profiles, but also on MT and immune activation.

Human polyomavirus JC replication and non-coding control region analysis in multiple sclerosis patients under natalizumab treatment.

In the last years, the treatment of multiple sclerosis (MS) patients with natalizumab has been associated with the occurrence of progressive multifocal leukoencephalopathy (PML) caused by human polyomavirus JC (JCV). Here, we have shown a significant correlation between patients with JC viruria and positive JC-specific antibody response and patients without JCV-specific antibodies after 1 year of natalizumab (p = 0.0006). Furthermore, JCV-specific quantitative PCR on urine and plasma samples, collected at the enrollment (t0) and every 4 months (t1, t2, t3) in the first year and at two time points (t4 and t5) in the second year of natalizumab treatment, indicated the prevalence of JC viremia rather than JC viruria only in the second year of treatment (p = 0.04). Moreover, the analysis of JCV non-coding control region (NCCR) sequences in peripheral blood mononuclear cells of patients with JC-specific antibodies after 12 natalizumab infusions (t3) revealed the presence of rearranged sequences, whereas the prevalence of genotypes 1A, 1B, and 4 was detected in these patients by VP1 sequence analysis. In summary, JC viruria evaluation seems to be useful to identify early those patients who do not already develop a humoral immune response against JCV. It may also be interesting to study the JCV NCCR rearrangements since they could give us new insights on the onset of neuro-invasive viral variants.

Immune activation, immunosenescence, and osteoprotegerin as markers of endothelial dysfunction in subclinical HIV-associated atherosclerosis.

HIV-infected patients have a significantly greater risk of cardiovascular disease. Several markers including osteoprotegerin have been shown to be involved in the development and progression of atherosclerosis. We investigated the relationship between T-cell phenotype, osteoprotegerin, and atherosclerosis evaluated by carotid intima-media thickness (c-IMT) in 94 HIV+ patients on suppressive antiretroviral therapy with Framingham score <10%. As for the control group, 24 HIV-negative subjects were enrolled. c-IMT was assessed by ultrasound. CD4+/CD8+ T-cell activation (CD38+ HLADR+) and senescence (CD57+ CD28-) were measured by flow cytometry. IL-6 and OPG levels were measured by ELISA kit. c-IMT was higher in HIV+ than in controls. Among HIV+ patients, 44.7% had pathological c-IMT (≥0.9 mm). CD8+ T-cell activation and senescence and OPG plasma levels were higher in HIV+ patients than in controls. Subjects with pathological c-IMT exhibited higher CD8+ immune activation and immunosenescence and OPG levels than subjects with normal c-IMT. Multivariate analysis showed that age, CD8+ CD38+ HLADR+, and CD8+ CD28- CD57+ were independently associated with pathological c-IMT. Several factors have been implicated in the pathogenesis of atherosclerosis in HIV patients. Immune activation and immunosenescence of CD8+ T cell together with OPG plasma levels might be associated with the development and progression of early atherosclerosis, even in the case of viral suppression.

The Impact of Cytomegalovirus Infection on Natural Killer and CD8+ T Cell Phenotype in Multiple Sclerosis.

Multiple sclerosis (MS) is a debilitating neurological disease that has been classified as an immune-mediated attack on myelin, the protective sheath of nerves. Some aspects of its pathogenesis are still unclear; nevertheless, it is generally established that viral infections influence the course of the disease. Cytomegalovirus (CMV) is a major pathogen involved in alterations of the immune system, including the expansion of highly differentiated cytotoxic CD8+ T cells and the accumulation of adaptive natural killer (NK) cells expressing high levels of the NKG2C receptor. In this study, we evaluated the impact of latent CMV infection on MS patients through the characterization of peripheral NK cells, CD8+ T cells, and NKT-like cells using flow cytometry. We evaluated the associations between immune cell profiles and clinical features such as MS duration and MS progression, evaluated using the Expanded Disability Status Scale (EDSS). We showed that NK cells, CD8+ T cells, and NKT-like cells had an altered phenotype in CMV-infected MS patients and displayed high levels of the NKG2C receptor. Moreover, in MS patients, increased NKG2C expression levels were found to be associated with higher EDSS scores. Overall, these results support the hypothesis that CMV infection imprints the immune system by modifying the phenotype and receptor repertoire of NK and CD8+ T cells, suggesting a detrimental role of CMV on MS progression.

Small fibre neuropathy frequently underlies the painful long-COVID syndrome.

ABSTRACT: Approximately 10% to 20% of individuals with previous SARS-CoV-2 infection may develop long-COVID syndrome, characterized by various physical and mental health issues, including pain. Previous studies suggested an association between small fibre neuropathy and pain in long-COVID cases. In this case-control study, our aim was to identify small fibre neuropathy in patients experiencing painful long-COVID syndrome. Clinical data, quantitative sensory testing, and skin biopsies were collected from 26 selected patients with painful long-COVID syndrome. We also examined 100 individuals with past COVID-19 infection, selecting 33 patients with painless long-COVID syndrome, characterized mainly by symptoms such as brain fog and fatigue, and 30 asymptomatic post-COVID-19 controls. Demographic and clinical variables were compared among these groups. Among the 26 patients with painful long-COVID syndrome, 12 had skin biopsy and/or quantitative sensory testing abnormalities compatible with small fibre neuropathy. Demographic and clinical data did not differ across patients with small fibre neuropathy, patients with painless long-COVID syndrome, and asymptomatic post-COVID-19 controls. This case-control study showed that approximately 50% of patients experiencing painful long-COVID syndrome had small fibre neuropathy. However, in our patient cohort, this specific post-COVID-19 complication was unrelated to demographic and COVID-19 clinical variables. Approximately half of our sample of patients with painful long-COVID symptoms met diagnostic criteria for small fibre neuropathy.

Blood Count and Renal Functionality Assessments in the Emergency Section Disclose Morbidity and Mortality in Omicron COVID-19 Patients: A Retrospective Study.

Background: SARS-CoV-2 is the coronavirus responsible for the COVID-19 pandemic. Even though we are no longer in a pandemic situation, people are still getting infected, some of them need hospitalization and a few of them die. Methods: We conducted a retrospective study including 445 patients who accessed the Emergency Section of Policlinico Umberto I, Rome, Italy, where they had routine blood exams. In this study, we focused on the complete blood count, serum creatinine and azotemia. The data were analyzed using ANOVA, Spearman correlation and ROC analyses. They were divided into four groups based on their clinical outcomes: (1) the emergency group (patients who had mild forms and were quickly discharged); (2) the hospital ward group (patients who were admitted to the emergency section and were then hospitalized in a COVID-19 ward); (3) the intensive care unit (ICU) group (patients who required intensive assistance after the admission in the emergency section); (4) the deceased group (patients who had a fatal outcome after admission to the emergency section). Results: We found significant changes for creatinine, azotemia, hematocrit, mean corpuscular hemoglobin concentration, basophils, monocytes, red blood cell distribution width, hemoglobin, hematocrit and red blood cell numbers using ANOVA according to their clinical outcomes, particularly for the deceased group. Also, we found linear correlations of clinical outcomes with eosinophils, hemoglobin, hematocrit, mean corpuscular hemoglobin concentration, lymphocyte, neutrophil, platelet and red blood cell number and red blood cell distribution width. Conclusions: This study discloses an early association between "classical" routine blood biomarkers and the severity of clinical outcomes in Omicron patients.

The Long-Term Immunogenicity of mRNABNT162b Third Vaccine Dose in Solid Organ Transplant Recipients.

We investigated humoral and T-cell response to a SARS-CoV-2 mRNA vaccine in solid organ transplant recipients (SOT-Rs) and healthy donors (HDs) before (T0) and after two (T1) and twelve months (T2) since the third dose administration. SOT-Rs were stratified according to the transplanted organ and to the time elapsed since the transplant. In SOT-Rs, detectable levels of anti-S antibodies were observed in 44%, 81% and 88% at T0, T1 and T2, respectively. Conversely, anti-S antibody levels were detected in 100% of HD at all time points. Lower antibody titers were observed in SOT-Rs compared to HDs, even stratifying by transplanted organs and the time elapsed since transplant. Lower percentages of responding and polyfunctional T-cells were observed in SOT-Rs as well as in each subgroup of SOT-Rs compared to HDs. At both T0 and T1, in SOT-Rs, a predominance of one cytokine production shortly was observed. Conversely, at T2, a dynamic change in the T-cells subset distribution was observed, similar to what was observed in HDs. In SOT-Rs, the third dose increased the rate of seroconversion, although anti-S levels remained lower compared to HDs, and a qualitatively inferior T-cell response to vaccination was observed. Vaccine effectiveness in SOT-Rs is still suboptimal and might be improved by booster doses and prophylactic strategies.

COVID-19 vaccination in cancer patients: Immune responses one year after the third dose.

Cancer patients (CPs), being immunosuppressed due to the treatment received or to the disease itself, are more susceptible to infections and their potential complications, showing therefore an increased risk of developing severe COVID-19 compared to the general population. We evaluated the immune responses to anti-SARS-CoV-2 vaccination in patients with solid tumors one year after the administration of the third dose and the effect of cancer treatment on vaccine immunogenicity was assessed. Healthy donors (HDs) were enrolled. Binding and neutralizing antibody (Ab) titers were evaluated using chemiluminescence immunoassay (CLIA) and Plaque Reduction Neutralization Test (PRNT) respectively. T-cell response was analyzed using multiparametric flow cytometry. CPs who were administered three vaccine doses showed lower Ab titers than CPs with four doses and HDs. Overall, a lower cell-mediated response was found in CPs, with a predominance of monofunctional T-cells producing TNFα. Lower Ab titers and a weaker T-cell response were observed in CPs without prior SARS-CoV-2 infection when compared to those with a previous infection. While no differences in the humoral response were found comparing immunotherapy and non-immunotherapy patients, a stronger T-cell response in CPs treated with immunotherapy was observed. Our results emphasize the need of booster doses in cancer patients to achieve a level of protection similar to that observed in healthy donors and underlines the importance of considering the treatment received to reach a proper immune response.

Neurofilament Expression as a Biomarker of Post-COVID-19 Sudden Sensorineural Hearing Loss.

Sudden sensorineural hearing loss (SSHL) affects a patient's quality of life and requires rapid treatment. The etiology is viral, vascular, and autoimmune, even though, in most cases, it remains idiopathic SSHL. Since 2019, several different complications have been identified following COVID-19 infection. The post-COVID-19 ENT manifestations reported in the literature are sore throat, headache, pharyngeal erythema, nasal obstruction, rhinorrhea, upper respiratory tract infection, and tonsil enlargement. Cases of SSHL, vestibular neuronitis, and audio-vestibular disorders (such as tinnitus, dizziness, and vertigo) have also been reported, albeit in a smaller percentage of patients. We reported our experience of a case of post-COVID-19 SSHL in the absence of any other type of post-COVID symptoms or brain and internal auditory canal magnetic resonance imaging and magnetic resonance angiography modifications. We aimed to identify a serological biomarker of sudden sensorineural hearing loss, and we also dosed and monitored the value of the serum neurofilament light (NfL). the best of our knowledge, this is the first report that associates SSHL and the serological increase in NfL as a potential biomarker of neuronal-disease-related damage.

COVID-19 Affects Serum Brain-Derived Neurotrophic Factor and Neurofilament Light Chain in Aged Men: Implications for Morbidity and Mortality.

BACKGROUND AND METHODS: Severe COVID-19 is known to induce neurological damage (NeuroCOVID), mostly in aged individuals, by affecting brain-derived neurotrophic factor (BDNF), matrix metalloproteinases (MMP) 2 and 9 and the neurofilament light chain (NFL) pathways. Thus, the aim of this pilot study was to investigate BDNF, MMP-2, MMP-9, and NFL in the serum of aged men affected by COVID-19 at the beginning of the hospitalization period and characterized by different outcomes, i.e., attending a hospital ward or an intensive care unit (ICU) or with a fatal outcome. As a control group, we used a novelty of the study, unexposed age-matched men. We also correlated these findings with the routine blood parameters of the recruited individuals. RESULTS: We found in COVID-19 individuals with severe or lethal outcomes disrupted serum BDNF, NFL, and MMP-2 presence and gross changes in ALT, GGT, LDH, IL-6, ferritin, and CRP. We also confirmed and extended previous data, using ROC analyses, showing that the ratio MMPs (2 and 9) versus BDNF and NFL might be a useful tool to predict a fatal COVID-19 outcome. CONCLUSIONS: Serum BDNF and NFL and/or their ratios with MMP-2 and MMP-9 could represent early predictors of NeuroCOVID in aged men.

Blood Biomarkers from the Emergency Department Disclose Severe Omicron COVID-19-Associated Outcomes.

BACKGROUND: Since its outbreak, Coronavirus disease 2019 (COVID-19), a life-threatening respiratory illness, has rapidly become a public health emergency with a devastating social impact. Lately, the Omicron strain is considered the main variant of concern. Routine blood biomarkers are, indeed, essential for stratifying patients at risk of severe outcomes, and a huge amount of data is available in the literature, mainly for the previous variants. However, only a few studies are available on early routine biochemical blood biomarkers for Omicron-afflicted patients. Thus, the aim and novelty of this study were to identify routine blood biomarkers detected at the emergency room for the early prediction of severe morbidity and/or mortality. METHODS: 449 COVID-19 patients from Sapienza University Hospital of Rome were divided into four groups: (1) the emergency group (patients with mild forms who were quickly discharged); (2) the hospital ward group (patients that after the admission in the emergency department were hospitalized in a COVID-19 ward); (3) the intensive care unit (ICU) group (patients that after the admission in the emergency department required intensive assistance); (4) the deceased group (patients that after the admission in the emergency department had a fatal outcome). RESULTS: ANOVA and ROC data showed that high-sensitivity troponin-T (TnT), fibrinogen, glycemia, C-reactive protein, lactate dehydrogenase, albumin, D-dimer myoglobin, and ferritin for both men and women may predict lethal outcomes already at the level of the emergency department. CONCLUSIONS: Compared to previous Delta COVID-19 parallel emergency patterns of prediction, Omicron-induced changes in TnT may be considered other early predictors of severe outcomes.

Immunogenicity and Efficacy of Vaccination in People Living with Human Immunodeficiency Virus.

People living with HIV (PLWH) remain at high risk of mortality and morbidity from vaccine-preventable diseases, even though antiretroviral therapy (ART) has restored life expectancy and general well-being. When, which, and how many doses of vaccine should be administered over the lifetime of PLWH are questions that have become clinically relevant. Immune responses to most vaccines are known to be impaired in PLWH. Effective control of viremia with ART and restored CD4+ T-cell count are correlated with an improvement in responsiveness to routine vaccines. However, the presence of immune alterations, comorbidities and co-infections may alter it. In this article, we provide a comprehensive review of the literature on immune responses to different vaccines in the setting of HIV infection, emphasizing the potential effect of HIV-related factors and presence of comorbidities in modulating such responses. A better understanding of these issues will help guide vaccination and prevention strategies for PLWH.

Evaluation of BAFF, APRIL and CD40L in Ocrelizumab-Treated pwMS and Infectious Risk.

BACKGROUND: The anti-CD20 monoclonal antibody ocrelizumab has been widely employed in the treatment of people with multiple sclerosis (pwMS). However, its B-cell-depleting effect may induce a higher risk of infectious events and alterations in the secretion of B-cell-activating factors, such as BAFF, APRIL and CD40L. METHODS: The aim of this study was to investigate plasma BAFF, APRIL and CD40L levels and their relationship with infectious risk in ocrelizumab-treated pwMS at baseline (T0), at 6 months (T6) and at 12 months (T12) after starting the treatment. As a control group, healthy donors (HD) were enrolled too. RESULTS: A total of 38 pwMS and 26 HD were enrolled. At baseline, pwMS showed higher plasma BAFF (p < 0.0001), APRIL (p = 0.0223) and CD40L (p < 0.0001) levels compared to HD. Compared to T0, plasma BAFF levels were significantly increased at both T6 and T12 (p < 0.0001 and p < 0.0001, respectively). Whereas plasma APRIL and CD40L levels were decreased at T12 (p = 0.0003 and p < 0.0001, respectively). When stratifying pwMS according to the development of an infectious event during the 12-month follow-up period in two groups-with (14) and without an infectious event (24)-higher plasma BAFF levels were observed at all time-points; significantly, in the group with an infectious event compared to the group without an infectious event (T0: p < 0.0001, T6: p = 0.0056 and T12: p = 0.0400). Conclusions: BAFF may have a role as a marker of immune dysfunction and of infectious risk.

Systemic, Mucosal Immune Activation and Psycho-Sexual Health in ART-Suppressed Women Living with HIV: Evaluating Biomarkers and Environmental Stimuli.

Gender medicine is now an approach that can no longer be neglected and must be considered in scientific research. We investigated the systemic and mucosal immune response in a population of women living with HIV (WLWH) who were receiving successful ART and the sexual and psychological repercussions of HIV infection on the women's health. As control group, healthy women (HW) matched for age and sex distribution, without any therapy, were included. In summary, our study highlighted the persistence of immune-inflammatory activation in our population, despite virological suppression and a normal CD4 cell count. We found a hyperactivation of the systemic monocyte and an increase in inflammatory cytokine concentrations at the systemic level. The analysis carried out showed a significantly higher risk of HPV coinfection in WLWH compared to HW. Furthermore, our data revealed that WLWH have a profile compatible with sexual dysfunction and generalized anxiety disorders. Our study underlines that patients living with HIV should be evaluated by multidisciplinary teams. These findings also support the idea that more and different immunological markers, in addition to those already used in clinical practice, are needed. Further studies should be carried out to clarify which of these could represent future therapy targets.

Biomarkers of Neurological Damage: From Acute Stage to Post-Acute Sequelae of COVID-19.

Background: Neurological symptoms (NS) in COVID-19 are related to both acute stage and long-COVID. We explored levels of brain injury biomarkers (NfL and GFAP) and myeloid activation marker (sCD163) and their implications on the CNS. Materials and Methods: In hospitalized COVID-19 patients plasma samples were collected at two time points: on hospital admission (baseline) and three months after hospital discharge (Tpost). Patients were stratified according to COVID-19 severity based on acute respiratory distress syndrome (ARDS) onset (severe and non-severe groups). A further stratification according to the presence of NS (with and without groups) at baseline (requiring a puncture lumbar for diagnostic purposes) and according to NS self-referred at Tpost was performed. Finally, cerebrospinal fluid (CSF) samples were collected from patients with NS present at baseline. Results: We enrolled 144 COVID-19 patients (62 female/82 male; median age [interquartile range, IQR]): 64 [55-77]) and 53 heathy donors (HD, 30 female/23 male; median age [IQR]: 64 [59-69]). At baseline, higher plasma levels of NfL, GFAP and sCD163 in COVID-19 patients compared to HD were observed (p < 0.0001, p < 0.0001 and p < 0.0001, respectively), especially in those with severe COVID-19 (p < 0.0001, p < 0.0001 and p < 0.0001, respectively). Patients with NS showed higher plasma levels of NfL, GFAP and sCD163 compared to those without (p = 0.0023, p < 0.0001 and 0.0370, respectively). At baseline, in COVID-19 patients with NS, positive correlations between CSF levels of sCD163 and CSF levels of NfL (ρ = 0.7536, p = 0.0017) and GFAP were observed (ρ = 0.7036, p = 0.0045). At Tpost, the longitudinal evaluation performed on 77 COVID-19 patients showed a significant reduction in plasma levels of NfL, GFAP and sCD163 compared to baseline (p < 0.0001, p < 0.0001 and p = 0.0413, respectively). Finally, at Tpost, in the severe group, higher plasma levels of sCD163 in patients with NS compared to those without were reported (p < 0.0001). Conclusions: High plasma levels of NfL, GFAP and sCD163 could be due to a proinflammatory systemic and brain response involving microglial activation and subsequent CNS damage. Our data highlight the association between myeloid activation and CNS perturbations.

Tissue Inhibitor of Matrix Metalloproteinases-1 (TIMP-1) and Pulmonary Involvement in COVID-19 Pneumonia.

Background: The aim of the study was to longitudinally evaluate the association between MMP-2, MMP-9, TIMP-1 and chest radiological findings in COVID-19 patients. Methods: COVID-19 patients were evaluated based on their hospital admission (baseline) and three months after hospital discharge (T post) and were stratified into ARDS and non-ARDS groups. As a control group, healthy donors (HD) were enrolled. Results: At the baseline, compared to HD (n = 53), COVID-19 patients (n = 129) showed higher plasma levels of MMP-9 (p < 0.0001) and TIMP-1 (p < 0.0001) and the higher plasma activity of MMP-2 (p < 0.0001) and MMP-9 (p < 0.0001). In the ARDS group, higher plasma levels of MMP-9 (p = 0.0339) and TIMP-1 (p = 0.0044) and the plasma activity of MMP-2 (p = 0.0258) and MMP-9 (p = 0.0021) compared to non-ARDS was observed. A positive correlation between the plasma levels of TIMP-1 and chest computed tomography (CT) score (ρ = 0.2302, p = 0.0160) was observed. At the T post, a reduction in plasma levels of TIMP-1 (p < 0.0001), whereas an increase in the plasma levels of MMP-9 was observed (p = 0.0088). Conclusions: The positive correlation between TIMP-1 with chest CT scores highlights its potential use as a marker of fibrotic burden. At T post, the increase in plasma levels of MMP-9 and the reduction in plasma levels of TIMP-1 suggested that inflammation and fibrosis resolution were still ongoing.