Perturbations of the T-cell receptor repertoire in response to SARS-CoV-2 in immunocompetent and immunocompromised individuals.

BACKGROUND: Functional T-cell responses are essential for virus clearance and long-term protection after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, whereas certain clinical factors, such as older age and immunocompromise, are associated with worse outcome. OBJECTIVE: We sought to study the breadth and magnitude of T-cell responses in patients with coronavirus disease 2019 (COVID-19) and in individuals with inborn errors of immunity (IEIs) who had received COVID-19 mRNA vaccine. METHODS: Using high-throughput sequencing and bioinformatics tools to characterize the T-cell receptor ß repertoire signatures in 540 individuals after SARS-CoV-2 infection, 31 IEI recipients of COVID-19 mRNA vaccine, and healthy controls, we quantified HLA class I- and class II-restricted SARS-CoV-2-specific responses and also identified several HLA allele-clonotype motif associations in patients with COVID-19, including a subcohort of anti-type 1 interferon (IFN-1)-positive patients. RESULTS: Our analysis revealed that elderly patients with COVID-19 with critical disease manifested lower SARS-CoV-2 T-cell clonotype diversity as well as T-cell responses with reduced magnitude, whereas the SARS-CoV-2-specific clonotypes targeted a broad range of HLA class I- and class II-restricted epitopes across the viral proteome. The presence of anti-IFN-I antibodies was associated with certain HLA alleles. Finally, COVID-19 mRNA immunization induced an increase in the breadth of SARS-CoV-2-specific clonotypes in patients with IEIs, including those who had failed to seroconvert. CONCLUSIONS: Elderly individuals have impaired capacity to develop broad and sustained T-cell responses after SARS-CoV-2 infection. Genetic factors may play a role in the production of anti-IFN-1 antibodies. COVID-19 mRNA vaccines are effective in inducing T-cell responses in patients with IEIs.

Multicenter analysis of neutrophil extracellular trap dysregulation in adult and pediatric COVID-19.

Dysregulation in neutrophil extracellular trap (NET) formation and degradation may play a role in the pathogenesis and severity of COVID-19; however, its role in the pediatric manifestations of this disease, including multisystem inflammatory syndrome in children (MIS-C) and chilblain-like lesions (CLLs), otherwise known as "COVID toes," remains unclear. Studying multinational cohorts, we found that, in CLLs, NETs were significantly increased in serum and skin. There was geographic variability in the prevalence of increased NETs in MIS-C, in association with disease severity. MIS-C and CLL serum samples displayed decreased NET degradation ability, in association with C1q and G-actin or anti-NET antibodies, respectively, but not with genetic variants of DNases. In adult COVID-19, persistent elevations in NETs after disease diagnosis were detected but did not occur in asymptomatic infection. COVID-19-affected adults displayed significant prevalence of impaired NET degradation, in association with anti-DNase1L3, G-actin, and specific disease manifestations, but not with genetic variants of DNases. NETs were detected in many organs of adult patients who died from COVID-19 complications. Infection with the Omicron variant was associated with decreased NET levels when compared with other SARS-CoV-2 strains. These data support a role for NETs in the pathogenesis and severity of COVID-19 in pediatric and adult patients.

Multicenter analysis of neutrophil extracellular trap dysregulation in adult and pediatric COVID-19.

Dysregulation in neutrophil extracellular trap (NET) formation and degradation may play a role in the pathogenesis and severity of COVID-19; however, its role in the pediatric manifestations of this disease including MIS-C and chilblain-like lesions (CLL), otherwise known as "COVID toes", remains unclear. Studying multinational cohorts, we found that, in CLL, NETs were significantly increased in serum and skin. There was geographic variability in the prevalence of increased NETs in MIS-C, in association with disease severity. MIS-C and CLL serum samples displayed decreased NET degradation ability, in association with C1q and G-actin or anti-NET antibodies, respectively, but not with genetic variants of DNases. In adult COVID-19, persistent elevations in NETs post-disease diagnosis were detected but did not occur in asymptomatic infection. COVID-19-affected adults displayed significant prevalence of impaired NET degradation, in association with anti-DNase1L3, G-actin, and specific disease manifestations, but not with genetic variants of DNases. NETs were detected in many organs of adult patients who died from COVID-19 complications. Infection with the Omicron variant was associated with decreased levels of NETs when compared to other SARS-CoV-2 strains. These data support a role for NETs in the pathogenesis and severity of COVID-19 in pediatric and adult patients. Summary: NET formation and degradation are dysregulated in pediatric and symptomatic adult patients with various complications of COVID-19, in association with disease severity. NET degradation impairments are multifactorial and associated with natural inhibitors of DNase 1, G-actin and anti-DNase1L3 and anti-NET antibodies. Infection with the Omicron variant is associated with decreased levels of NETs when compared to other SARS-CoV-2 strains.

Antibody responses to the SARS-CoV-2 vaccine in individuals with various inborn errors of immunity.

BACKGROUND: SARS-CoV-2 vaccination is recommended in patients with inborn errors of immunity (IEIs); however, little is known about immunogenicity and safety in these patients. OBJECTIVE: We sought to evaluate the impact of genetic diagnosis, age, and treatment on antibody response to COVID-19 vaccine and related adverse events in a cohort of patients with IEIs. METHODS: Plasma was collected from 22 health care worker controls, 81 patients with IEIs, and 2 patients with thymoma; the plasma was collected before immunization, 1 to 6 days before the second dose of mRNA vaccine, and at a median of 30 days after completion of the immunization schedule with either mRNA vaccine or a single dose of Johnson & Johnson's Janssen vaccine. Anti-spike (anti-S) and anti-nucleocapsid antibody titers were measured by using a luciferase immunoprecipitation systems method. Information on T- and B-cell counts and use of immunosuppressive drugs was extracted from medical records, and information on vaccine-associated adverse events was collected after each dose. RESULTS: Anti-S antibodies were detected in 27 of 46 patients (58.7%) after 1 dose of mRNA vaccine and in 63 of 74 fully immunized patients (85.1%). A lower rate of seroconversion (7 of 11 [63.6%]) was observed in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy. Previous use of rituximab and baseline counts of less than 1000 CD3+ T cells/mL and less than 100 CD19+ B cells/mL were associated with lower anti-S IgG levels. No significant adverse events were reported. CONCLUSION: Vaccinating patients with IEIs is safe, but immunogenicity is affected by certain therapies and gene defects. These data may guide the counseling of patients with IEIs regarding prevention of SARS-CoV-2 infection and the need for subsequent boosts.

Cutaneous barrier leakage and gut inflammation drive skin disease in Omenn syndrome.

BACKGROUND: Severe early-onset erythroderma and gut inflammation, with massive tissue infiltration of oligoclonal activated T cells are the hallmark of Omenn syndrome (OS). OBJECTIVE: The impact of altered gut homeostasis in the cutaneous manifestations of OS remains to be clarified. METHODS: We analyzed a cohort of 15 patients with OS and the 129Sv/C57BL/6 knock-in Rag2R229Q/R229Q (Rag2R229Q) mouse model. Homing phenotypes of circulating lymphocytes were analyzed by flow cytometry. Inflammatory cytokines and chemokines were examined in the sera by ELISA and in skin biopsies by immunohistochemistry and in situ RNA hybridization. Experimental colitis was induced in mice by dextran sulfate sodium salt. RESULTS: We show that memory/activated T cells from patients with OS and from the Rag2R229Q mouse model of OS abundantly express the skin homing receptors cutaneous lymphocyte associated antigen and CCR4 (Ccr4), associated with high levels of chemokine C-C motif ligands 17 and 22. Serum levels of LPS are also elevated. A broad Th1/Th2/Th17 inflammatory signature is detected in the periphery and in the skin. Increased Tlr4 expression in the skin of Rag2R229Q mice is associated with enhanced cutaneous inflammation on local and systemic administration of LPS. Likewise, boosting colitis in Rag2R229Q mice results in increased frequency of Ccr4+ splenic T cells and worsening of skin inflammation, as indicated by epidermal thickening, enhanced epithelial cell activation, and dermal infiltration by Th1 effector T cells. CONCLUSIONS: These results support the existence of an interplay between gut and skin that can sustain skin inflammation in OS.

A pharmacodynamic study of the P-glycoprotein antagonist CBT-1® in combination with paclitaxel in solid tumors.

BACKGROUND: This pharmacodynamic trial evaluated the effect of CBT-1® on efflux by the ATP binding cassette (ABC) multidrug transporter P-glycoprotein (Pgp/MDR1/ABCB1) in normal human cells and tissues. CBT-1® is an orally administered bisbenzylisoquinoline Pgp inhibitor being evaluated clinically. Laboratory studies showed potent and durable inhibition of Pgp, and in phase I studies CBT-1® did not alter the pharmacokinetics of paclitaxel or doxorubicin. METHODS: CBT-1® was dosed at 500 mg/m2 for 7 days; a 3-hour infusion of paclitaxel at 135 mg/m2 was administered on day 6. Peripheral blood mononuclear cells (PBMCs) were obtained prior to CBT-1® administration and on day 6 prior to the paclitaxel infusion. (99m)Tc-sestamibi imaging was performed on the same schedule. The area under the concentration-time curve from 0-3 hours (AUC(0-3)) was determined for (99m)Tc-sestamibi. RESULTS: Twelve patients were planned and enrolled. Toxicities were minimal and related to paclitaxel (grade 3 or 4 neutropenia in 18% of cycles). Rhodamine efflux from CD56+ PBMCs was a statistically significant 51%-100% lower (p < .0001) with CBT-1®. Among 10 patients who completed imaging, the (99m)Tc-sestamibi AUC(0-3) for liver (normalized to the AUC(0-3) of the heart) increased from 34.7% to 100.8% (median, 71.9%; p < .0001) after CBT-1® administration. Lung uptake was not changed. CONCLUSION: CBT-1® is able to inhibit Pgp-mediated efflux from PBMCs and normal liver to a degree observed with Pgp inhibitors studied in earlier clinical trials. Combined with its ease of administration and lack of toxicity, the data showing inhibition of normal tissue Pgp support further studies with CBT-1® to evaluate its ability to modulate drug uptake in tumor tissue. DISCUSSION: Although overexpression of ABCB1 and other ABC transporters has been linked with poor outcome following chemotherapy efforts to negate that through pharmacologic inhibition have generally failed. This is thought to be a result of several factors, including (a) failure to select patients with tumors in which ABCB1 is a dominant resistance mechanism; (b) inhibitors that were not potent, or that impaired drug clearance; and (c) the existence of other mechanisms of drug resistance, including other ABC transporters. Although an animal model for Pgp has been lacking, recent studies have exploited a Brca1(-/-); p53(-/-) mouse model of hereditary breast cancer that develops sporadic tumors similar to cancers in women harboring BRCA1 mutations. Treatment with doxorubicin, docetaxel, or the poly(ADP-ribose) polymerase inhibitor olaparib brings about shrinkage, but resistance eventually emerges. Overexpression of the Abcb1a gene, the mouse ortholog of human ABCB1, has been shown to be a mechanism of resistance in a subset of these tumors. Treating mice with resistant tumors with olaparib plus the Pgp inhibitor tariquidar resensitized the tumors to olaparib. Although results in this animal model support a new look at Pgp as a target, in this era of "targeted therapies," trial designs that directly assess modulation of drug uptake, including quantitative nuclear imaging, should be pursued before clinical efficacy assessments are undertaken. Such assessment should be performed with compounds that inhibit tissue Pgp without altering the pharmacokinetics of chemotherapeutic agents. This pharmacodynamic study demonstrated that CBT-1®, inhibits Pgp-mediated efflux from PBMCs and normal liver.

A pharmacodynamic study of docetaxel in combination with the P-glycoprotein antagonist tariquidar (XR9576) in patients with lung, ovarian, and cervical cancer.

PURPOSE: P-glycoprotein (Pgp) antagonists have been difficult to develop because of complex pharmacokinetic interactions and a failure to show meaningful results. Here we report the results of a pharmacokinetic and pharmacodynamic trial using a third-generation, potent, noncompetitive inhibitor of Pgp, tariquidar (XR9576), in combination with docetaxel. EXPERIMENTAL DESIGN: In the first treatment cycle, the pharmacokinetics of docetaxel (40 mg/m(2)) were evaluated after day 1 and day 8 doses, which were administered with or without tariquidar (150 mg). (99m)Tc-sestamibi scanning and CD56(+) mononuclear cell rhodamine efflux assays were conducted to assess Pgp inhibition. In subsequent cycles, 75 mg/m(2) docetaxel was administered with 150 mg tariquidar every 3 weeks. RESULTS: Forty-eight patients were enrolled onto the trial. Nonhematologic grade 3/4 toxicities in 235 cycles were minimal. Tariquidar inhibited Pgp-mediated rhodamine efflux from CD56(+) cells and reduced (99m)Tc-sestamibi clearance from the liver. There was striking variability in basal sestamibi uptake; a 12% to 24% increase in visible lesions was noted in 8 of 10 patients with lung cancer. No significant difference in docetaxel disposition was observed in pairwise comparison with and without tariquidar. Four partial responses (PR) were seen (4/48); 3 in the non-small cell lung cancer (NSCLC) cohort, measuring 40%, 57%, and 67% by RECIST, and 1 PR in a patient with ovarian cancer. CONCLUSIONS: Tariquidar is well tolerated, with less observed systemic pharmacokinetic interaction than previous Pgp antagonists. Variable effects of tariquidar on retention of sestamibi in imageable lung cancers suggest that follow-up studies assessing tumor drug uptake in this patient population would be worthwhile.