Immune response to ART initiation in advanced HIV infection.

OBJECTIVES: Our objective was to compare the immunological responses to commonly used antiretroviral therapy (ART) regimens among people with advanced HIV in the USA and to assess virological outcomes and regimen persistence. METHODS: This study included ART-naïve adults with advanced HIV infection (CD4 cell count <200 cells/µL) initiating ART with bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF), boosted darunavir (bDRV), dolutegravir (DTG), or elvitegravir (EVG/c)-containing regimens between 1 January 2018 and 31 December 2020 in the Observational Pharmaco-Epidemiology Research and Analysis (OPERA) cohort. Cox proportional hazards models and linear mixed models with random intercept were fit with inverse probability of treatment weighting. RESULTS: Overall, 1349 people with advanced HIV (816 B/F/TAF, 253 DTG, 146 EVG/c, 134 bDRV) were followed for a median of 22 months. Compared with B/F/TAF, a lower likelihood of achieving a CD4 cell count ≥200 cells/µL was observed with bDRV (hazard ratio [HR] 0.76; 95% confidence interval [CI] 0.60-0.96), DTG (HR 0.82; 95% CI 0.69-0.98), and EVG/c (HR 0.73; 95% CI 0.57-0.93). All groups had a similar pattern of CD4:CD8 ratio changes: a rapid increase in the first 6 months (ranging from +0.15 to +0.16 units), followed by a slower increase thereafter. Only 40 individuals (4%) achieved CD4:CD8 ratio normalization (≥1). B/F/TAF was associated with a faster time to virological suppression (viral load <200 copies/mL) and a slower time to discontinuation compared with other regimens. CONCLUSIONS: Among people with advanced HIV infection, B/F/TAF initiation was associated with faster CD4 cell count recovery and favourable virological outcomes compared with bDRV-, DTG-, and EVG/c-based regimens, although no difference was observed in CD4:CD8 ratio changes over time across regimens.

Vaccination in Kidney Transplant Candidates.

Background: Kidney transplant (KT) candidates have historically low immunization rates against recommended vaccines. A retrospective single-center study of contemporary KT candidates was conducted to assess vaccination rates and vaccine uptake. Methods: All KT candidates ≥18 y evaluated between January 1, 2020, and December 31, 2020, were retrospectively reviewed for history of prior vaccination against tetanus, diphtheria, and pertussis; 13-valent pneumococcal conjugate vaccine; 23-valent pneumococcal polysaccharide vaccine; and recombinant zoster vaccine. Positive hepatitis A IgG total, hepatitis B surface antibody, measles, mumps, rubella, and varicella IgG were assessed as surrogate markers of immunity. Vaccine uptake among vaccine-eligible candidates was also assessed. Results: Among 150 KT candidates, the rate of prior vaccination against tetanus, diphtheria, and pertussis; 13-valent pneumococcal conjugate vaccine; 23-valent pneumococcal polysaccharide vaccine; and recombinant zoster vaccine (latter among patients ≥50 y) was found to be as low as 11%. Hepatitis A IgG total, hepatitis B surface antibody, measles, mumps, rubella, and varicella IgG seropositivity rates were 30%, 66%, 88%, 78%, 90%, and 96%, respectively. Only 7 (5%) of 150 patients had complete immunization or seropositivity. Five (3%) of 143 vaccine-eligible patients declined vaccination. Hepatitis A vaccine declination was relatively common with 15 (16%) of 94 vaccine-eligible patients declining it. Conclusions: KT candidates have low baseline rates of prior immunization/seropositivity against most recommended vaccines. Overall vaccine uptake among eligible candidates was high.

Frailty and COVID-19 mRNA Vaccine Antibody Response in the COVID-19 Community Research Partnership.

BACKGROUND: COVID-19 has disproportionately affected older adults. Frailty has been associated with impaired vaccine response in other vaccine types, but the impact of frailty on mRNA vaccine response is undefined. METHODS: Observational study of adults aged 55 and older from 1 U.S. health care system between January 22, 2021 and September 16, 2021 with self-reported Moderna or Pfizer COVID-19 mRNA vaccine and an electronic frailty index (eFI) score from their medical record (n = 1 677). Participants' frailty status was compared with positive antibody detection (seroconversion) following full vaccination and subsequent loss of positive antibody detection (seroreversion) using logistic regression models. RESULTS: Of 1 677 older adults with median (interquartile range) age, 67 (62 and 72) years, and frailty status (nonfrail: 879 [52%], prefrail: 678 [40%], and frail: 120 [7.2%]), seroconversion was not detected in 23 (1.4%) over 60 days following full vaccination. Frail individuals were less likely to seroconvert than nonfrail individuals, adjusted odds ratio (OR) 3.75, 95% confidence interval (CI; 1.04, 13.5). Seroreversion was detected in 50/1 631 individuals (3.1%) over 6 months of median follow-up antibody testing. Frail individuals were more likely to serorevert than nonfrail individuals, adjusted OR 3.02, 95% CI (1.17, 7.33). CONCLUSION: Overall antibody response to COVID-19 mRNA vaccination was high across age and frailty categories. While antibody detection is an incomplete descriptor of vaccine response, the high sensitivity of this antibody combined with health-system data reinforce our conclusions that frailty is an independent predictor of impaired antibody response to the COVID-19 mRNA vaccines. Frailty should be considered in vaccine studies and prevention strategies.

Analysis of accumulated SARS-CoV-2 seroconversion in North Carolina: The COVID-19 Community Research Partnership.

INTRODUCTION: The COVID-19 Community Research Partnership is a population-based longitudinal syndromic and sero-surveillance study. The study includes over 17,000 participants from six healthcare systems in North Carolina who submitted over 49,000 serology results. The purpose of this study is to use these serology data to estimate the cumulative proportion of the North Carolina population that has either been infected with SARS-CoV-2 or developed a measurable humoral response to vaccination. METHODS: Adult community residents were invited to participate in the study between April 2020 and February 2021. Demographic information was collected and daily symptom screen was completed using a secure, HIPAA-compliant, online portal. A portion of participants were mailed kits containing a lateral flow assay to be used in-home to test for presence of anti-SARS-CoV-2 IgM or IgG antibodies. The cumulative proportion of participants who tested positive at least once during the study was estimated. A standard Cox proportional hazards model was constructed to illustrate the probability of seroconversion over time up to December 20, 2020 (before vaccines available). A separate analysis was performed to describe the influence of vaccines through February 15, 2021. RESULTS: 17,688 participants contributed at least one serology result. 68.7% of the population were female, and 72.2% were between 18 and 59 years of age. The average number of serology results submitted per participant was 3.0 (±1.9). By December 20, 2020, the overall probability of seropositivity in the CCRP population was 32.6%. By February 15, 2021 the probability among healthcare workers and non-healthcare workers was 83% and 49%, respectively. An inflection upward in the probability of seropositivity was demonstrated around the end of December, suggesting an influence of vaccinations, especially for healthcare workers. Among healthcare workers, those in the oldest age category (60+ years) were 38% less likely to have seroconverted by February 15, 2021. CONCLUSIONS: Results of this study suggest more North Carolina residents may have been infected with SARS-CoV-2 than the number of documented cases as determined by positive RNA or antigen tests. The influence of vaccinations on seropositivity among North Carolina residents is also demonstrated. Additional research is needed to fully characterize the impact of seropositivity on immunity and the ultimate course of the pandemic.

Antifungal use in immunocompetent, critically ill patients with pneumonia does not improve clinical outcomes.

PURPOSE: To determine if treating bronchoalveolar lavage (BAL) culture-positive patients with antifungal therapy impacted mortality compared to not treating due to presumed colonization. METHODS: We conducted a retrospective study of immunocompetent, critically ill adult patients from 2010 to 2014. Patients with a BAL culture-positive for Candida or unspeciated yeast and a clinical suspicion of pneumonia were included. The treatment group received an antifungal agent for at least 5 days, and the control group received either no antifungal therapy or an antifungal agent for less than 48 h. Recruitment occurred in a 2:1 ratio of untreated versus treated patients. RESULTS: Seventy-five patients were included. In-hospital mortality was similar between treated and untreated groups (24% vs. 26%, P = 0.85). Length of stay and duration of mechanical ventilation also did not differ between the two groups. CONCLUSION: We did not observe a difference in mortality or clinical outcomes in patients treated with antifungal agents. Presumptive antifungal therapy for BAL-positive Candida or yeast in immunocompetent patients did not result in improved clinical outcomes.

Modified vaccinia Ankara: potential as an alternative smallpox vaccine.

Despite the declaration of smallpox eradication in 1980, the existence of variola stockpiles and the threat of bioterrorism demand that immunity to smallpox through vaccination be maintained. Although the currently available vaccine was used for the most successful medical intervention ever accomplished, it also is associated with side effects that are difficult to accept in a vaccine for a disease that has not been present for >25 years. Herein, we review alternative approaches to maintaining immunity to smallpox through vaccination with attenuated poxviruses, and we suggest modified vaccinia Ankara (MVA) as a leading candidate for an alternative smallpox vaccine.

Clinical features and outcomes of paramyxoviral infection in lung transplant recipients treated with ribavirin.

BACKGROUND: Paramyxoviral infections are reported in 6% to 21% of lung transplant recipients. Aerosolized ribavirin is used to treat paramyoxviral infections, but data on outcomes of this treatment in lung transplant patients are limited. METHODS: Lung recipients treated with aerosolized ribavirin from 1992 through 2000 for pulmonary respiratory syncytial virus (RSV) or parainfluenza virus (PIV) infection were assessed for the following variables: age; gender; underlying diagnosis; time from transplantation; duration of illness; clinical symptoms; and change from baseline FEV(1) (forced expiratory volume in 1 second). Outcomes included FEV(1) values at 30 and 90 days, need for intubation, development of acute rejection or obliterative bronchiolitis (OB) in the year after treatment; and 90-day and overall mortality. RESULTS: Fifteen patients received ribavirin for a median of 5 days (range 3 to 7) for 17 episodes of RSV (n = 12) or PIV (n = 5) infection. The clinical presentations of RSV and PIV infection were similar. Infection occurred a median of 520 days (range 7 to 1700) after transplantation. Three episodes required intubation; 2 episodes were fatal accounting for a 90-day mortality per episode of 12%. The FEV(1) at presentation declined by 25% (range 4% to 44%) from baseline. In 3 patients the FEV(1) did not return to baseline by 90 days or thereafter. All 3 patients had underlying pulmonary fibrosis (IPF) vs no IPF in 0 of 9 evaluable patients who recovered (p = 0.009). There was no correlation between response to ribavirin and subsequent development of OB. CONCLUSIONS: About 33% of lung transplant patients with lower respiratory tract paramyxoviral infections who were treated with inhaled ribavirin died or did not return to baseline FEV(1). This effect was acute and not associated with later complications, including OB. Underlying IPF may be a risk factor for failure to return to baseline. Larger, prospective, multicenter studies are required to confirm these findings.

Infections due to non-neoformans cryptococcal species.

The incidence of infections due to non-neoformans cryptococcal species is increasing. Risk factors associated with infections due to these organisms include immunosuppression and clinical syndromes are similar to those encountered with Cryptococcus neoformans. Therapy with antifungal agents is often successful.

Safety, immunogenicity and efficacy of modified vaccinia Ankara (MVA) against Dryvax challenge in vaccinia-naïve and vaccinia-immune individuals.

Modified vaccinia Ankara (MVA) was evaluated as an alternative to Dryvax in vaccinia-naïve and vaccinia-immune adult volunteers. Subjects received intramuscular MVA or placebo followed by Dryvax challenge at 3 months. Two or more doses of MVA prior to Dryvax reduced severity of lesion formation, decreased magnitude and duration of viral shedding, and augmented post-Dryvax vaccinia-specific CD8(+) T cell responses and extracellular enveloped virus protein-specific antibody responses. MVA vaccination is safe and immunogenic and improves the safety and immunogenicity of subsequent Dryvax vaccination supporting the potential for using MVA as a vaccine in the general population to improve immunity to orthopoxviruses.

RhoA signaling is required for respiratory syncytial virus-induced syncytium formation and filamentous virion morphology.

Respiratory syncytial virus (RSV) is an important human pathogen that can cause severe and life-threatening respiratory infections in infants, the elderly, and immunocompromised adults. RSV infection of HEp-2 cells induces the activation of RhoA, a small GTPase. We therefore asked whether RhoA signaling is important for RSV replication or syncytium formation. The treatment of HEp-2 cells with Clostridium botulinum C3, an enzyme that ADP-ribosylates and specifically inactivates RhoA, inhibited RSV-induced syncytium formation and cell-to-cell fusion, although similar levels of PFU were released into the medium and viral protein expression levels were equivalent. Treatment with another inhibitor of RhoA signaling, the Rho kinase inhibitor Y-27632, yielded similar results. Scanning electron microscopy of C3-treated infected cells showed reduced numbers of single blunted filaments, in contrast to the large clumps of long filaments in untreated infected cells. These data suggest that RhoA signaling is associated with filamentous virus morphology, cell-to-cell fusion, and syncytium formation but is dispensable for the efficient infection and production of infectious virus in vitro. Next, we developed a semiquantitative method to measure spherical and filamentous virus particles by using sucrose gradient velocity sedimentation. Fluorescence and transmission electron microscopy confirmed the separation of spherical and filamentous forms of infectious virus into two identifiable peaks. The C3 treatment of RSV-infected cells resulted in a shift to relatively more spherical virions than those from untreated cells. These data suggest that viral filamentous protuberances characteristic of RSV infection are associated with RhoA signaling, are important for filamentous virion morphology, and may play a role in initiating cell-to-cell fusion.

Role of plasma membrane lipid microdomains in respiratory syncytial virus filament formation.

The fusion protein (F) of respiratory syncytial virus (RSV) is the envelope glycoprotein responsible for the characteristic cytopathology of syncytium formation. RSV has been shown to bud from selective areas of the plasma membrane as pleomorphic virions, including both filamentous and round particles. With immunofluorescent microscopy, we demonstrated evidence of RSV filaments incorporating the fusion protein F and colocalizing with a lipid microdomain-specific fluorescent dye, 1,1-dihexadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate. Western blot analysis of Triton X-100 cold-extracted membrane fractions confirmed the presence of RSV proteins within the lipid microdomains. RSV proteins also colocalized with cellular proteins associated with lipid microdomains, caveolin-1, and CD44, as well as with RhoA, a small GTPase. ADP-ribosylation of RhoA by Clostridium botulinum exotoxin inactivated RhoA signaling and resulted in the absence of RSV-induced syncytia despite no significant change in viral titer. We demonstrated an overall decrease in both the number and length of the viral filaments and a shift in the localization of F to nonlipid microdomain regions of the membrane in the presence of C3 toxin. This suggests that the selective incorporation of RSV proteins into lipid microdomains during virus assembly may lead to critical interactions of F with cellular proteins, resulting in microvillus projections necessary for the formation of filamentous virus particles and syncytium formation. Thus, manipulation of membrane lipid microdomains may lead to alterations in the production of viral filaments and RSV pathogenesis and provide a new pharmacologic target for RSV therapy.

Modified vaccinia virus Ankara immunization protects against lethal challenge with recombinant vaccinia virus expressing murine interleukin-4.

Recent events have raised concern over the use of pathogens, including variola virus, as biological weapons. Vaccination with Dryvax is associated with serious side effects and is contraindicated for many people, and the development of a safer effective smallpox vaccine is necessary. We evaluated an attenuated vaccinia virus, modified vaccinia virus Ankara (MVA), by use of a murine model to determine its efficacy against an intradermal (i.d.) or intranasal (i.n.) challenge with vaccinia virus (vSC8) or a recombinant vaccinia virus expressing murine interleukin-4 that exhibits enhanced virulence (vSC8-mIL4). After an i.d. challenge, 15 of 16 mice who were inoculated with phosphate-buffered saline developed lesions, one dose of intramuscularly administered MVA was partially protective (3 of 16 mice developed lesions), and the administration of two or three doses of MVA was completely protective (0 of 16 mice developed lesions). In unimmunized mice, an i.n. challenge with vSC8 caused a significant but self-limited illness, while vSC8-mIL4 resulted in lethal infections. Immunization with one or two doses of MVA prevented illness and reduced virus titers in mice who were challenged with either vSC8 or vSC8-mIL4. MVA induced a dose-related neutralizing antibody and vaccinia virus-specific CD8+-T-cell response. Mice immunized with MVA were fully protected from a low-dose vSC8-mIL4 challenge despite a depletion of CD4+ cells, CD8+ cells, or both T-cell subsets or an antibody deficiency. CD4+- or CD8+-T-cell depletion reduced the protection against a high-dose vSC8-mIL4 challenge, and the depletion of both T-cell subsets was associated with severe illness and higher vaccinia virus titers. Thus, MVA induces broad humoral and cellular immune responses that can independently protect against a molecularly modified lethal poxvirus challenge in mice. These data support the continued development of MVA as an alternative candidate vaccine for smallpox.