We evaluated whether biomarkers of age-related neuronal injury and amyloid metabolism are associated with neurocognitive impairment (NCI) in people with and without HIV (PWH, PWoH). This was a cross-sectional study of virally suppressed PWH and PWoH. NCI was assessed using a validated test battery; global deficit scores (GDS) quantified overall performance. Biomarkers in cerebrospinal fluid (CSF) were quantified by immunoassay: neurofilament light (NFL), total Tau (tTau), phosphorylated Tau 181 (pTau181), amyloid beta (Aβ)42, and Aβ40. Factor analysis was used to reduce biomarker dimensionality. Participants were 256 virally suppressed PWH and 42 PWoH, 20.2% female, 17.1% Black, 7.1% Hispanic, 60.2% non-Hispanic White, and 15.6% other race/ethnicities, mean (SD) age 56.7 (6.45) years. Among PWH, the best regression model for CSF showed that higher tTau (β = 0.723, p = 3.79e-5) together with lower pTau181 (β = -0.510, p = 0.0236) best-predicted poor neurocognitive performance. In univariable analysis, only higher tTau was significantly correlated with poor neurocognitive performance (tTau r = 0.214, p = 0.0006; pTau181 r = 0.00248, p = 0.969). Among PWoH, no CSF biomarkers were significantly associated with worse NCI. Predicted residual error sum of squares (PRESS) analysis showed no evidence of overfitting. Poorer neurocognitive performance in aging PWH was associated with higher CSF tTau, a marker of age-related neuronal injury, but not with biomarkers of amyloid metabolism. The findings suggest that HIV might interact with age-related neurodegeneration to contribute to cognitive decline in PWH.

Purpose

In other cancer types, HPV infection has been reported to coincide with overexpression of HER2 (ERBB2) and HER3 (ERBB3); however, the association between HER2 or HER3 expression and dimer formation in HNSCC has not been reported. Overexpression of HER2 and HER3 may contribute to resistance to EGFR inhibitors, including cetuximab, although the contribution of HPV in modulating cetuximab response remains unknown. Determination of heterodimerization of HER receptors is challenging and has not been reported in HNSCC. The present study aimed to determine the expression of HER proteins in HPV(+) versus HPV(-) HNSCC tumors using a proximity-based protein expression assay (VeraTag), and to determine the efficacy of HER-targeting agents in HPV(+) and HPV(-) HNSCC cell lines.

Experimental design

Expression of total HER1, HER2, and HER3, p95HER2, p-HER3, HER1:HER1 homodimers, HER2:HER3 heterodimers, and the HER3-PI3K complex in 88 HNSCC was determined using VeraTag, including 33 baseline tumors from individuals treated in a trial including cetuximab. Inhibition of cell growth and protein activation with cetuximab and afatinib was compared in HPV(+) and HPV(-) cetuximab-resistant cell lines.

Results

Expression of total HER2, total HER3, HER2:HER3 heterodimers, and the HER3:PI3K complex were significantly elevated in HPV(+) HNSCC. Total EGFR was significantly increased in HPV(-) HNSCC where VeraTag assay results correlated with IHC. Afatinib significantly inhibited cell growth when compared with cetuximab in the HPV(+) and HPV(-) cetuximab-resistant HNSCC cell lines.

Conclusions

These findings suggest that agents targeting multiple HER proteins may be effective in the setting of HPV(+) HNSCC and/or cetuximab resistance.

Cetuximab, an anti-EGFR monoclonal antibody (mAb), is approved for advanced head and neck squamous cell carcinoma (HNSCC) but benefits a minority. An established tumor-intrinsic resistance mechanism is cross-talk between the EGFR and hepatocyte growth factor (HGF)/cMet pathways. Dual pathway inhibition may overcome cetuximab resistance. This Phase I study evaluated the combination of cetuximab and ficlatuzumab, an anti-HGF mAb, in patients with recurrent/metastatic HNSCC. The primary objective was to establish the recommended Phase II dose (RP2D). Secondary objectives included overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). Mechanistic tumor-intrinsic and immune biomarkers were explored. Thirteen patients enrolled with no dose-limiting toxicities observed at any dose tier. Three evaluable patients were treated at Tier 1 and nine at Tier 2, which was determined to be the RP2D (cetuximab 500 mg/m² and ficlatuzumab 20 mg/kg every 2 weeks). Median PFS and OS were 5.4 (90% CI = 1.9-11.4) and 8.9 (90% CI = 2.7-15.2) months, respectively, with a confirmed ORR of 2 of 12 (17%; 90% CI = 6-40%). High circulating soluble cMet levels correlated with poor survival. An increase in peripheral T cells, particularly the CD8⁺ subset, was associated with treatment response whereas progression was associated with expansion of a distinct myeloid population. This well-tolerated combination demonstrated promising activity in cetuximab-resistant, advanced HNSCC.

Background

Neurofilament light (NFL) chain concentrations, reflecting axonal damage, are seen in several polyneuropathies but have not been studied in human immunodeficiency virus (HIV) distal sensory polyneuropathy (DSP). We evaluated NFL in cerebrospinal fluid (CSF) and plasma in relation to DSP in people with HIV (PWH) from 2 independent cohorts and in people without HIV (PWoH).

Methods

Cohort 1 consisted of PWH from the CHARTER Study. Cohort 2 consisted of PWH and PWoH from the HIV Neurobehavioral Research Center (HNRC). We evaluated DSP signs and symptoms in both cohorts. Immunoassays measured NFL in CSF for all and for plasma as well in Cohort 2.

Results

Cohort 1 consisted of 111 PWH, mean ± SD age 56.8 ± 8.32 years, 15.3% female, 38.7% Black, 49.6% White, current CD4+ T-cells (median, interquartile range [IQR]) 532/µL (295, 785), 83.5% with plasma HIV RNA ≤50 copies/mL. Cohort 2 consisted of 233 PWH of similar demographics to PWH in Cohort 1 but also 51 PWoH, together age 58.4 ± 6.68 years, 41.2% female, 18.0% Black, Hispanic, non-Hispanic White 52.0%, 6.00% White. In both cohorts of PWH, CSF and plasma NFL were significantly higher in both PWH with DSP signs. Findings were similar, albeit not significant, for PWoH. The observed relationships were not explained by confounds.

Conclusions

Both plasma and CSF NFL were elevated in PWH and PWoH with DSP. The convergence of our findings with others demonstrates that NFL is a reliable biomarker reflecting peripheral nerve injury. Biomarkers such as NFL might provide, validate, and optimize clinical trials of neuroregenerative strategies in HIV DSP.

Background Postacute sequelae of COVID-19 (PASC) and HIV are both associated with reduced exercise capacity, but whether SARS-CoV-2 or PASC are associated with exercise capacity among people with HIV (PWH) is unknown. We hypothesized that PWH with PASC would have reduced exercise capacity from chronotropic incompetence. Methods and Results We conducted cross-sectional cardiopulmonary exercise testing within a COVID recovery cohort that included PWH with and without prior SARS-CoV-2 infection and people without HIV with prior SARS-CoV-2 infection (controls). We evaluated associations of HIV, SARS-CoV-2, and PASC with exercise capacity (peak oxygen consumption) and chronotropy (adjusted heart rate reserve). We included 83 participants (median age, 54 years; 35% women; 37 PWH): 23 out of 37 (62%) PWH and all 46 controls had prior SARS-CoV-2 infection, and 11 out of 23 (48%) PWH and 28 out of 46 (61%) without HIV had PASC. Peak oxygen consumption was reduced among PWH versus controls (80% predicted versus 99%, P=0.005), a difference of 5.5 mL/kg per minute (95% CI, 2.7-8.2; P<0.001). Chronotropic incompetence was more prevalent among PWH (38% versus 11%, P=0.002), with lower adjusted heart rate reserve (60% versus 83%, P<0.0001) versus controls. Among PWH, SARS-CoV-2 coinfection and PASC were not associated with exercise capacity. Chronotropic incompetence was more common among PWH with PASC: 7 out of 11 (64%) with PASC versus 7 out of 26 (27%) without PASC (P=0.04). Conclusions Exercise capacity and chronotropy are lower among PWH compared with individuals with SARS-CoV-2 infection without HIV. Among PWH, SARS-CoV-2 infection and PASC were not strongly associated with reduced exercise capacity. Chronotropic incompetence may be a common underrecognized mechanism of exercise intolerance among PWH, especially those with cardiopulmonary PASC.

Shortness of breath, chest pain, and palpitations occur as postacute sequelae of COVID-19, but whether symptoms are associated with echocardiographic abnormalities, cardiac biomarkers, or markers of systemic inflammation remains unknown. In a cross-sectional analysis, we assessed symptoms, performed echocardiograms, and measured biomarkers among adults more than 8 weeks after confirmed SARS-CoV-2 infection. We modeled associations between symptoms and baseline characteristics, echocardiographic findings, and biomarkers using logistic regression. We enrolled 102 participants at a median of 7.2 months following COVID-19 onset; 47 individuals reported dyspnea, chest pain, or palpitations. Median age was 52 years, and 41% of participants were women. Female sex, hospitalization, IgG antibody against SARS-CoV-2 receptor binding domain, and C-reactive protein were associated with symptoms. Regarding echocardiographic findings, 4 of 47 participants (9%) with symptoms had pericardial effusions compared with 0 of 55 participants without symptoms; those with effusions had a median of 4 symptoms compared with a median of 1 symptom in those without effusions. There was no strong evidence for a relationship between symptoms and echocardiographic functional parameters or other biomarkers. Among adults more than 8 weeks after SARS-CoV-2 infection, SARS-CoV-2 RBD antibodies, markers of inflammation, and, possibly, pericardial effusions are associated with cardiopulmonary symptoms. Investigation into inflammation as a mechanism underlying postacute sequelae of COVID-19 is warranted.

Background

The biological processes associated with postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC) are unknown.

Methods

We measured soluble markers of inflammation in a SARS-CoV-2 recovery cohort at early (<90 days) and late (>90 days) timepoints. We defined PASC as the presence of 1 or more coronavirus disease 2019 (COVID-19)-attributed symptoms beyond 90 days. We compared fold-changes in marker values between those with and without PASC using mixed-effects models with terms for PASC and early and late recovery time periods.

Results

During early recovery, those who went on to develop PASC generally had higher levels of cytokine biomarkers including tumor necrosis factor-α (1.14-fold higher mean ratio [95% confidence interval {CI}, 1.01-1.28]; P = .028) and interferon-γ-induced protein 10 (1.28-fold higher mean ratio [95% CI, 1.01-1.62]; P = .038). Among those with PASC, there was a trend toward higher interleukin 6 levels during early recovery (1.29-fold higher mean ratio [95% CI, .98-1.70]; P = .07), which became more pronounced in late recovery (1.44-fold higher mean ratio [95% CI, 1.11-1.86]; P < .001). These differences were more pronounced among those with a greater number of PASC symptoms.

Conclusions

Persistent immune activation may be associated with ongoing symptoms following COVID-19. Further characterization of these processes might identify therapeutic targets for those experiencing PASC.

Long COVID, a type of post-acute sequelae of SARS-CoV-2 (PASC), has been associated with sustained elevated levels of immune activation and inflammation. However, the mechanisms that drive this inflammation remain unknown. Inflammation during acute coronavirus disease 2019 could be exacerbated by microbial translocation (from the gut and/or lung) to blood. Whether microbial translocation contributes to inflammation during PASC is unknown. We did not observe a significant elevation in plasma markers of bacterial translocation during PASC. However, we observed higher levels of fungal translocation - measured as β-glucan, a fungal cell wall polysaccharide - in the plasma of individuals experiencing PASC compared with those without PASC or SARS-CoV-2-negative controls. The higher β-glucan correlated with higher inflammation and elevated levels of host metabolites involved in activating N-methyl-d-aspartate receptors (such as metabolites within the tryptophan catabolism pathway) with established neurotoxic properties. Mechanistically, β-glucan can directly induce inflammation by binding to myeloid cells (via Dectin-1) and activating Syk/NF-κB signaling. Using a Dectin-1/NF-κB reporter model, we found that plasma from individuals experiencing PASC induced higher NF-κB signaling compared with plasma from negative controls. This higher NF-κB signaling was abrogated by piceatannol (Syk inhibitor). These data suggest a potential targetable mechanism linking fungal translocation and inflammation during PASC.

Background

Mechanisms underlying persistent cardiopulmonary symptoms after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (postacute sequelae of coronavirus disease 2019 [COVID-19; PASC] or "long COVID") remain unclear. This study sought to elucidate mechanisms of cardiopulmonary symptoms and reduced exercise capacity.

Methods

We conducted cardiopulmonary exercise testing (CPET), cardiac magnetic resonance imaging (CMR) and ambulatory rhythm monitoring among adults >1 year after SARS-CoV-2 infection, compared those with and those without symptoms, and correlated findings with previously measured biomarkers.

Results

Sixty participants (median age, 53 years; 42% female; 87% nonhospitalized; median 17.6 months after infection) were studied. At CPET, 18/37 (49%) with symptoms had reduced exercise capacity (<85% predicted), compared with 3/19 (16%) without symptoms (P = .02). The adjusted peak oxygen consumption (VO2) was 5.2 mL/kg/min lower (95% confidence interval, 2.1-8.3; P = .001) or 16.9% lower percent predicted (4.3%-29.6%; P = .02) among those with symptoms. Chronotropic incompetence was common. Inflammatory markers and antibody levels early in PASC were negatively correlated with peak VO2. Late-gadolinium enhancement on CMR and arrhythmias were absent.

Conclusions

Cardiopulmonary symptoms >1 year after COVID-19 were associated with reduced exercise capacity, which was associated with earlier inflammatory markers. Chronotropic incompetence may explain exercise intolerance among some with "long COVID."

Background

SARS-CoV-2 nucleocapsid antigen can be detected in plasma, but little is known about its performance as a diagnostic test for acute SARS-CoV-2 infection or infectious viral shedding among nonhospitalized individuals.

Methods

We used data generated from anterior nasal and blood samples collected in a longitudinal household cohort of SARS-CoV-2 cases and contacts. Participants were classified as true positives if polymerase chain reaction (PCR) positive for SARS-CoV-2 and as true negatives if PCR negative and seronegative. Infectious viral shedding was determined by the cytopathic effect from viral culture. Stratified by 7 days after symptom onset, we constructed receiver operating characteristic (ROC) curves to describe optimized accuracy (Youden index), optimized sensitivity, and specificity.

Results

Of 80 participants, 58 (73%) were true positives while 22 (27%) were true negatives. Using the manufacturer's cutoff of 1.25 pg/mL for evaluating infection, sensitivity was higher from 0 to 7 days (77.6% [95% confidence interval {CI}, 64%-88.2%]) than from 8 to 14 days (43.2% [95% CI, 31.1%-54.5%]) after symptom onset; specificity was unchanged at 100% (95% CI, 88.1%-100%). This test had higher sensitivity (100% [95% CI, 88.4%-100%]) and lower specificity (65% [95% CI, 40.8%-84.6%]) for infectious viral shedding as compared with infection, particularly within the first week of symptom onset. Although the presence of N-antigen correlated with infectious viral shedding (r = 0.63; P < .01), sensitivity still declined over time. Additional cutoffs from ROC curves were identified to optimize sensitivity and specificity.

Conclusions

We found that this SARS-CoV-2 N-antigen test was highly sensitive for detecting early but not late infectious viral shedding, making it a viable screening test for community-dwelling individuals to inform isolation practices.