Immunogenicity of COVID-19 vaccines and their effect on HIV reservoir in older people with HIV

Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity of these vaccines and their effects on HIV reservoirs are not available. Our study on 68 PWH and 23 HIV-negative participants aged 55 and older post-three vaccine doses showed equally strong anti-spike IgG responses in serum and saliva through week 48 from baseline, while PWH salivary IgA responses were low. PWH had diminished live-virus neutralization responses after two vaccine doses, which were 'rescued' post-booster. Spike-specific T cell immunity was enhanced in PWH with normal CD4+ T cell count, suggesting Th1 imprinting. The frequency of detectable HIV viremia increased post-vaccination, but vaccines did not affect the size of the HIV reservoir in most PWH, except those with low-level viremia. Thus, older PWH require three doses of COVID-19 vaccine for maximum protection, while individuals with unsuppressed viremia should be monitored for adverse reactions from HIV reservoirs.

Scan-Associated Distress in People Affected by Cancer: A Qualitative Systematic Review

OBJECTIVE

The term "scanxiety" has been coined to describe the anxiety commonly associated with individuals undergoing cancer-related imaging. Despite the prevalence and severity of scanxiety across various clinical and demographic populations, there remains a significant lack of qualitative insights from existing studies that effectively capture patients' experiences of scanxiety in their own words. Therefore, this review addresses the following research question: What are the experiences of scanxiety distress among people affected by cancer across the cancer care continuum?

DATA SOURCES

Following the PRISMA methodology, a meta-aggregation of qualitative studies was performed, encompassing patients of all age groups who had been diagnosed with cancer or were indicated for a cancer-related scan. Of the 556 articles screened, 15 were deemed eligible for inclusion in the analysis.

CONCLUSION

The three overarching themes of 1) experience of "scan-itis," 2) experience of "patient-clinician support," and 3) development of self-management strategies reveal the complex and interconnected factors that influence scanxiety in individuals undergoing cancer-related imaging. These findings emphasized distress experienced by patients during the waiting period for scan results, the act of viewing the results, and even the delivery of "bad" news. Consequently, patients expressed a strong desire for increased information, communication, and empathy from attending healthcare providers. Patients also report a myriad of self-coping strategies to manage their scanxiety well before, during, and after their scan appointment.

IMPLICATIONS FOR NURSING PRACTICE

The study highlights the need for targeted interventions for those undergoing cancer-related scans, including increased awareness and education for health professionals regarding scanxiety.

Immunogenicity of COVID-19 vaccines and their effect on the HIV reservoir in older people with HIV

Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity of these vaccines and their effects on HIV reservoirs are not available. We followed 68 PWH aged 55 and older and 23 age-matched HIV-negative individuals for 48 weeks from the first vaccine dose, after the total of three doses. All PWH were on antiretroviral therapy (cART) and had different immune status, including immune responders (IR), immune non-responders (INR), and PWH with low-level viremia (LLV). We measured total and neutralizing Ab responses to SARS-CoV-2 spike and RBD in sera, total anti-spike Abs in saliva, frequency of anti-RBD/NTD B cells, changes in frequency of anti-spike, HIV gag/nef-specific T cells, and HIV reservoirs in peripheral CD4 + T cells. The resulting datasets were used to create a mathematical model for within-host immunization. Various regimens of BNT162b2, mRNA-1273, and ChAdOx1 vaccines elicited equally strong anti-spike IgG responses in PWH and HIV - participants in serum and saliva at all timepoints. These responses had similar kinetics in both cohorts and peaked at 4 weeks post-booster (third dose), while half-lives of plasma IgG also dramatically increased post-booster in both groups. Salivary spike IgA responses were low, especially in INRs. PWH had diminished live virus neutralizing titers after two vaccine doses which were 'rescued' after a booster. Anti-spike T cell immunity was enhanced in IRs even in comparison to HIV - participants, suggesting Th1 imprinting from HIV, while in INRs it was the lowest. Increased frequency of viral 'blips' in PWH were seen post-vaccination, but vaccines did not affect the size of the intact HIV reservoir in CD4 + T cells in most PWH, except in LLVs. Thus, older PWH require three doses of COVID-19 vaccine to maximize neutralizing responses against SARS-CoV-2, although vaccines may increase HIV reservoirs in PWH with persistent viremia.

A184 REPURPOSING DRUGS FOR SPLEEN TYROSINE KINASE (SYK) PEDIATRIC PATIENTS USING HIGH-THROUGHPUT SCREENING

Background

Spleen Tyrosine Kinase (SYK) is a cytosolic, non-receptor tyrosine kinase with an imperative role in immune and non-immune processes. Recently, we identified six gain-of-function SYK variants in patients that presented multi-organ inflammation and immune dysregulation. The SYK variants displayed constitutive SYK phosphorylation in human embryonic kidney (HEK) 293T, colonic epithelial cells (SW480), and in knock-in heterozygous SYK mice. These observations mark SYK as a therapeutic target for autoimmune diseases.

Phenotype drug discovery accelerates this process and can be done successfully with an appropriate phenotype. A possible phenotype displayed by SYK variants is SYK phosphorylation, as high-throughput screening can identify hit compounds that reduce the constitutive activation of phosphorylated SYK (p-SYK).

Aims

Aim 1: Determine the screening phenotype with wildtype (WT) and SYK S550Y variant in HEK293T cells. Recently, we observed increased phosphorylation in gain-of-function SYK variants We hypothesize that we can use phosphorylated-SYK (p-SYK) levels to identify hit compounds that can decrease the kinase activity in these variants. With stable transfected SYK WT and SYK S550Y HEK293T cell-line, protein analyses will be completed to characterize the appropriate screening phenotype.

Aim 2

Establish an assay for high-throughput drug screening. We will utilize homogenous time-resolved fluorescence (HTRF) assay. The signal measured from HTRF is positively proportional to the level of p-SYK; therefore, we expect that S550Y cells will have a higher signal than the WT.

Aim 3

Validate hit compounds in HEK293T and zebrafish. We will create a dose-response curve with the hit compounds in in vitro and in vivo models.

Methods

We will use stable transfection to established overexpressing SYK WT and S550Y HEK293T cells. We will apply homogenous time-resolved fluorescence (HTRF) to quantify p-SYK levels during the drug screening.

Results

Protein analyses have verified high expression of p-SYK in stable transfected HEK293T cells. No stimulation was required, as the cells showed an increased phosphorylation level at baseline. Downstream signaling partners such as p-ERK and p-JNK of the MAPK pathway displayed an upregulation. This suggests that the sustained activation of p-SYK may consequently affect cellular processes and contribute to the clinical manifestations observed in patients.

Conclusions

This research study will identify hit compounds that can produce a safe and effective biological response in pediatric patients with gain-of-function SYK variants. Personalizing medicine throughout high-throughput drug screening can accelerate drug repurposing for pediatric patients with multiple systemic diseases and immune dysregulation.

Funding Agencies

None

Preclinical evaluation of a SARS-CoV-2 mRNA vaccine PTX-COVID19-B

Safe and effective vaccines are needed to end the COVID-19 pandemic. Here, we report the preclinical development of a lipid nanoparticle–formulated SARS-CoV-2 mRNA vaccine, PTX-COVID19-B. PTX-COVID19-B was chosen among three candidates after the initial mouse vaccination results showed that it elicited the strongest neutralizing antibody response against SARS-CoV-2. Further tests in mice and hamsters indicated that PTX-COVID19-B induced robust humoral and cellular immune responses and completely protected the vaccinated animals from SARS-CoV-2 infection in the lung. Studies in hamsters also showed that PTX-COVID19-B protected the upper respiratory tract from SARS-CoV-2 infection. Mouse immune sera elicited by PTX-COVID19-B vaccination were able to neutralize SARS-CoV-2 variants of concern, including the Alpha, Beta, Gamma, and Delta lineages. No adverse effects were induced by PTX-COVID19-B in either mice or hamsters. Based on these results, PTX-COVID19-B was authorized by Health Canada to enter clinical trials in December 2020 with a phase 2 clinical trial ongoing.

Abstract P1-09-02: Homologous repair deficiency (HRD) as measure to predict the effect of carboplatin on survival in the neoadjuvant phase II trial GeparSixto in triple-negative early breast cancer

Introduction

Addition of carboplatin to anthracycline/taxane-based neoadjuvant chemotherapy has shown to improve pathological complete response (pCR; ypT0 ypN0) rates in patients with triple-negative breast cancer (TNBC) in two large phase II studies (GeparSixto: von Minckwitz et al, Lancet Oncol 2014, CALGB 40603: Sikov WM, J Clin Oncol 2015). Participants of the GeparSixto study showed an improvement of pCR rate from 36.9 to 53.2% (p=0.005) and DFS by absolute 9% (HR 0.56 95% CI 0.33-0.96] p=0.035) with the addition of carboplatin in the TNBC subgroup. No effect was observed in the HER2-positive subgroup. We here report results on homologous repair deficiency (HRD) status in relation to pCR and DFS in the TNBC subgroup.

Patients and Methods

In the GeparSixto trial (NCT01426880), patients were treated for 18 weeks with paclitaxel 80mg/m2 q1w and non-pegylated-liposomal doxorubicin (NPLD) 20mg/m2 q1w. Patients with TNBC (N=315) received concurrently bevacizumab 15mg/kg i.v. q2w until surgery. All patients were randomized 1:1 to receive concurrently carboplatin AUC 1.5-2 q1w vs no carboplatin. Carboplatin dose was reduced from AUC 2.0 to 1.5 by an amendment after 330 patients. Primary objective is pCR rate (ypT0 ypN0). Event free survival (EFS), and overall survival (OS) were secondary objectives. HR Deficiency status was assessed on FFPE material from pretherapeutic core biopsies. HR Deficiency was defined as either HRD score high or a BRCA mutation.

Results

HRD status was measurable in 193 of 315 TNBC patients. 101 patients of them were randomly assigned to receive carboplatin and 92 to no additional carboplatin. After median follow-up of 34.3 months 43 event free survival (EFS) events have been reported.

HR deficiency was detected in 136 (70.5%) tumors of which 79 (58.1%) showed high HRD score with intact tBRCA. HR deficiency independently predicted pCR (ypT0is ypN0) (odds ratio (OR) 2.506, CI 1.243-5.051, p=0.009). Adding carboplatin to PM significantly increased the pCR rate from 36.6% to 63.2% in HR deficient tumors with intact tBRCA (p=0.018), only marginally from 61.9% to 72.7% in BRCA mutated tumors (p=0.406), and moderately from 20.0% to 40.7% in HR non-deficient tumors (p=0.086). In general, patients with HRD deficient tumors had a better ESF than non HRD deficient ones (HR 1.805 (0.985-3.309); p=0.0526). Patients with high HRD score had an insignificant trend towards an improved EFS compared to those with low HRD score (HR 1.546 (0.764-3.127) p=0.2223). HRD deficiency did not predict carboplatin effect in patients without BRCA mutation (HR 0.8617). In multivariable analysis, only therapy, clinical nodal status before treatment, and lymphocyte predominant breast cancer were significant prognostic on EFS.

Conclusion

Within the GeparSixto study HR deficiency (either HRD score high or BRCA mutation) was associated with a higher pCR in general and an improved EFS. The effect of carboplatin could not be predicted by HR deficiency in this relatively small study. However, the results will help to understand the role of HR deficiency and the value of the HRD score in TNBC especially in patients without BRCA mutation.

Citation Format: von Minckwitz G, Timms K, Untch M, Elkin EP, Hahnen E, Fasching PA, Schneeweiss A, Salat CT, Rezai M, Blohmer J-U, Zahm D-M, Jackisch C, Gerber B, Klare P, Kümmel S, Paepke S, Schmutzler R, Chau S, Reid J, Hartman A-R, Nekljudova V, Weber KE, Loibl S. Homologous repair deficiency (HRD) as measure to predict the effect of carboplatin on survival in the neoadjuvant phase II trial GeparSixto in triple-negative early breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-09-02.

Three cases of atypical pneumonia caused by Chlamydophila psittaci

Psittacosis is a zoonotic disease caused by Chlamydophila psittaci. The most common presentation is atypical pneumonia. Three cases of pneumonia of varying severity due to psittacosis are described. All patients had a history of avian contact. The diagnosis was confirmed by molecular detection of Chlamydophila psittaci in respiratory specimens. The cases showed good recovery with doxycycline treatment. Increased awareness of psittacosis can shorten diagnostic delay and improve patient outcomes.

Cryptococcosis in apparently immunocompetent patients

BACKGROUND

Few reports have described the clinical and microbiological features of cryptococcosis in immunocompetent patients.

AIM

To compare clinical presentations and outcomes of cryptococcosis in immunocompetent vs. immunocompromised patients.

DESIGN

Retrospective case series.

METHODS

All culture- or histology-confirmed cases (n = 46) of cryptococcosis in two acute hospitals in Hong Kong (1995-2005) were included. Clinical presentations, rates of fungaemia, cerebrospinal fluid (CSF) parameters and clinical outcomes were recorded.

RESULTS

Twenty patients (43.5%) were apparently immunocompetent, 17 (37.0%) had predisposing factors other than HIV infection, and 9 (19.6%) were HIV-positive. Thirty-one (67.4%) presented with meningitis, four (8.7%) with pulmonary cryptococcosis, and 11 (23.9%) with extraneural, extrapulmonary cryptococcosis. Of the immunocompetent patients with retrievable isolates (n = 8), three (37.5%) were Cryptococcus gattii; all isolates (n = 6) from immunocompromised patients were Cryptococcus neoformans var. grubii. Immunocompetent patients more commonly presented with meningitis (80.0% vs. 47.1%, p = 0.03), and tended toward lower rates of fungaemia (10.0% vs. 35.3%, p = 0.06) and mortality (25.0% vs. 52.9%, p = 0.06). Death was associated with fungaemia (p = 0.01) and underlying malignancy (p < 0.01). In cryptococcal meningitis, immunocompetent patients had longer mean time from illness onset to presentation (34.4 vs. 12.6 days, p = 0.02), more intense inflammatory responses (CSF: white blood cells 108 vs. 35 x 10(9)/l, p = 0.03; protein 1.61 g/l vs. 0.79 g/l, p = 0.07), less fungaemia (0% vs. 26.7%, p = 0.04) and more satisfactory clinical outcomes (81.3% vs. 46.7%, p = 0.04).

DISCUSSION

A substantial proportion of patients with cryptococcosis are apparently immunocompetent. C. neoformans var. grubii and C. gattii are the common causes. Immunocompetent patients tend to present with localized, indolent neurological disease, with more intense inflammatory responses but better clinical outcomes.

Twisted gastrulation can function as a BMP antagonist

Bone morphogenetic proteins (BMPs), including the fly homologue Decapentaplegic (DPP), are important regulators of early vertebrate and invertebrate dorsal-ventral development. An evolutionarily conserved BMP regulatory mechanism operates from fly to fish, frog and mouse to control the dorsal-ventral axis determination. Several secreted factors, including the BMP antagonist chordin/Short gastrulation (SOG), modulate the activity of BMPs. In Drosophila, Twisted gastrulation (TSG) is also involved in dorsal-ventral patterning, yet the mechanism of its function is unclear. Here we report the characterization of the vertebrate Tsg homologues. We show that Tsg can block BMP function in Xenopus embryonic explants and inhibits several ventral markers in whole-frog embryos. Tsg binds directly to BMPs and forms a ternary complex with chordin and BMPs. Coexpression of Tsg with chordin leads to a more efficient inhibition of the BMP activity in ectodermal explants. Unlike other known BMP antagonists, however, Tsg also reduces several anterior markers at late developmental stages. Our data suggest that Tsg can function as a BMP inhibitor in Xenopus; furthermore, Tsg may have additional functions during frog embryogenesis.

Alterations in CER6, a gene identical to CUT1, differentially affect long-chain lipid content on the surface of pollen and stems

Very long chain lipids contribute to the hydrophobic cuticle on the surface of all land plants and are an essential component of the extracellular pollen coat in the Brassicaceae. Mutations in Arabidopsis CER genes eliminate very long chain lipids from the cuticle surface and, in some cases, from the pollen coat. In Arabidopsis, the loss of pollen coat lipids can disrupt interactions with the stigma, inhibiting pollen hydration and causing sterility. We have positionally cloned CER6 and demonstrate that a wild-type copy complements the cer6-2 defect. In addition, we have identified a fertile, intragenic suppressor, cer6-2R, that partially restores pollen coat lipids but does not rescue the stem wax defect, suggesting an intriguing difference in the requirements for CER6 activity on stems and the pollen coat. Importantly, analysis of this suppressor demonstrates that low amounts of very long chain lipids are sufficient for pollen hydration and germination. The predicted CER6 amino acid sequence resembles that of fatty acid-condensing enzymes, consistent with its role in the production of epicuticular and pollen coat lipids >28 carbons long. DNA sequence analysis revealed the nature of the cer6-1, cer6-2, and cer6-2R mutations, and segregation analysis showed that CER6 is identical to CUT1, a cDNA previously mapped to a different chromosome arm. Instead, we have determined that a new gene, CER60, with a high degree of nucleotide and amino acid similarity to CER6, resides at the original CUT1 locus.

Impact of heparin bonding on pediatric cardiopulmonary bypass: a prospective randomized study

BACKGROUND

Heparin-coated circuits reduce the inflammatory response to cardiopulmonary bypass in adult patients; however, little is known about its effects in the pediatric population. Two studies were performed to assess this technology's impact on inflammation and clinical outcomes.

METHODS

In a pilot study, complement and interleukins were measured in 19 patients who had either uncoated cardiopulmonary bypass circuits or heparin-bonded circuits. Subsequently, 23 additional patients were studied in a randomized fashion. Respiratory function and blood product utilization were recorded.

RESULTS

In the pilot study, heparin-bonded circuit patients had less complement 3a (p < 0.001) and interleukin-8 (p < 0.05) compared with uncoated cardiopulmonary bypass circuit patients. The randomized study revealed that the heparin-bonded circuit was associated with reduced complement 3a (p = 0.02). Multiple variable analysis revealed that the following postoperative variables were increased with bypass time (p = 0.01) and diminished with heparin-bonded circuits: interleukins (p = 0.01), peak airway pressures (p = 0.05), and prothrombin time (p = 0.03).

CONCLUSIONS

Heparin-bonded circuits significantly reduce cytokines and complement during cardiopulmonary bypass and lower interleukin levels postbypass; they were also associated with improved pulmonary and coagulation function. Heparin-bonded circuits ameliorate the systemic inflammatory response in pediatric patients from cardiopulmonary bypass.

An experimental comparative study on the characteristics of ventricular fibrillation during cardiac arrest and methoxamine administration

The effect of a pure alpha-adrenergic agent, methoxamine on ventricular fibrillation (VF) amplitude and the relation between hemodynamic parameters and survival in a rodent cardiopulmonary resuscitation (CPR) model were studied. Our results suggested that: 1) VF amplitude decreased during untreated VF, but it increased during pericardial chest compression: 2) methoxamine significantly increased the mean aortic pressure (MAP) and coronary perfusion pressure (CPP) but not VF amplitude, and the survival also increased due to elevation of CPP; and 3) all surviving animals with successful defibrillation had a higher VF amplitude.