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1.
Open Forum Infect Dis ; 10(8): ofad369, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37577118

ABSTRACT

Background: Therapeutically immunosuppressed transplant recipients exhibit attenuated responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines. To elucidate the kinetics and variant cross-protection of vaccine-induced antibodies in this population, we conducted a prospective longitudinal study in heart and lung transplant recipients receiving the SARS-CoV-2 messenger RNA (mRNA) 3-dose vaccination series. Methods: We measured longitudinal serum antibody and neutralization responses against the ancestral and major variants of SARS-CoV-2 in SARS-CoV-2-uninfected lung (n = 18) and heart (n = 17) transplant recipients, non-lung-transplanted patients with cystic fibrosis (n = 7), and healthy controls (n = 12) before, during, and after the primary mRNA vaccination series. Results: Among healthy controls, strong anti-spike responses arose immediately following vaccination and displayed cross-neutralization against all variants. In contrast, among transplant recipients, after the first 2 vaccine doses, increases in antibody concentrations occurred gradually, and cross-neutralization was completely absent against the Omicron B.1.1.529 variant. However, most (73%) of the transplant recipients had a significant response to the third vaccine dose, reaching levels comparable to those of healthy controls, with improved but attenuated neutralization of immune evasive variants, particularly Beta, Gamma, and Omicron. Responses in non-lung-transplanted patients with cystic fibrosis paralleled those in healthy controls. Conclusions: In this prospective, longitudinal analysis of variant-specific antibody responses, lung and heart transplant recipients display delayed and defective responses to the first 2 SARS-CoV-2 vaccine doses but significantly augmented responses to a third dose. Gaps in antibody-mediated immunity among transplant recipients are compounded by decreased neutralization against Omicron variants, leaving many patients with substantially weakened immunity against currently circulating variants.

2.
JCI Insight ; 7(19)2022 10 10.
Article in English | MEDLINE | ID: mdl-36214224

ABSTRACT

Protective immunity against SARS-CoV-2 infection after COVID-19 vaccination may differ by variant. We enrolled vaccinated (n = 39) and unvaccinated (n = 11) individuals with acute, symptomatic SARS-CoV-2 Delta or Omicron infection and performed SARS-CoV-2 viral load quantification, whole-genome sequencing, and variant-specific antibody characterization at the time of acute illness and convalescence. Viral load at the time of infection was inversely correlated with antibody binding and neutralizing antibody responses. Across all variants tested, convalescent neutralization titers in unvaccinated individuals were markedly lower than in vaccinated individuals. Increases in antibody titers and neutralizing activity occurred at convalescence in a variant-specific manner. For example, among individuals infected with the Delta variant, neutralizing antibody responses were weakest against BA.2, whereas infection with Omicron BA.1 variant generated a broader response against all tested variants, including BA.2.


Subject(s)
AIDS Vaccines , COVID-19 , Influenza Vaccines , Papillomavirus Vaccines , Respiratory Syncytial Virus Vaccines , SAIDS Vaccines , Antibodies, Neutralizing , Antibodies, Viral , BCG Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , Convalescence , Diphtheria-Tetanus-Pertussis Vaccine , Humans , Measles-Mumps-Rubella Vaccine , Neutralization Tests , SARS-CoV-2
4.
medRxiv ; 2022 Mar 02.
Article in English | MEDLINE | ID: mdl-35262089

ABSTRACT

Clinical features of SARS-CoV-2 Omicron variant infection, including incubation period and transmission rates, distinguish this variant from preceding variants. However, whether the duration of shedding of viable virus differs between omicron and previous variants is not well understood. To characterize how variant and vaccination status impact shedding of viable virus, we serially sampled symptomatic outpatients newly diagnosed with COVID-19. Anterior nasal swabs were tested for viral load, sequencing, and viral culture. Time to PCR conversion was similar between individuals infected with the Delta and the Omicron variant. Time to culture conversion was also similar, with a median time to culture conversion of 6 days (interquartile range 4-8 days) in both groups. There were also no differences in time to PCR or culture conversion by vaccination status.

5.
medRxiv ; 2022 Mar 03.
Article in English | MEDLINE | ID: mdl-35262094

ABSTRACT

There is increasing evidence that the risk of SARS-CoV-2 infection among vaccinated individuals is variant-specific, suggesting that protective immunity against SARS-CoV-2 may differ by variant. We enrolled vaccinated (n = 39) and unvaccinated (n = 11) individuals with acute, symptomatic SARS-CoV-2 Delta or Omicron infection and performed SARS-CoV-2 viral load quantification, whole-genome sequencing, and variant-specific antibody characterization at the time of acute illness and convalescence. Viral load at the time of infection was inversely correlated with antibody binding and neutralizing antibody responses. Increases in antibody titers and neutralizing activity occurred at convalescence in a variant-specific manner. Across all variants tested, convalescent neutralization titers in unvaccinated individuals were markedly lower than in vaccinated individuals. For individuals infected with the Delta variant, neutralizing antibody responses were weakest against BA.2, whereas infection with Omicron BA.1 variant generated a broader response against all tested variants, including BA.2.

6.
medRxiv ; 2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34282426

ABSTRACT

BACKGROUND: Therapeutically immunosuppressed transplant recipients exhibit attenuated responses to COVID-19 vaccines. To better understand the immune alterations that determined poor vaccine response, we correlated quantities of circulating T and B cell subsets at baseline with longitudinal serologic responses to SARS-CoV-2 mRNA vaccination in heart and lung transplant recipients. METHODS: Samples at baseline and at approximately 8 and 30 days after each vaccine dose for 22 heart and lung transplant recipients with no history of COVID-19, four heart and lung transplant recipients with prior COVID-19 infection, and 12 healthy controls undergoing vaccination were analyzed. Anti-spike protein receptor binding domain (RBD) IgG and pseudovirus neutralization activity were measured. Proportions of B and T cell subsets at baseline were comprehensively quantitated. RESULTS: At 8-30 days post vaccination, healthy controls displayed robust anti-RBD IgG responses, whereas heart and lung transplant recipients showed minimally increased responses. A parallel absence of activity was observed in pseudovirus neutralization. In contrast, three of four (75%) transplant recipients with prior COVID-19 infection displayed robust responses at levels comparable to controls. Baseline levels of activated PD-1 + HLA-DR + CXCR5 - CD4 + T cells (also known as T peripheral helper [T PH ] cells) and CD4+ T cells strongly predicted the ability to mount a response. CONCLUSIONS: Immunosuppressed patients have defective vaccine responses but can be induced to generate neutralizing antibodies after SARS-CoV-2 infection. Strong correlations of vaccine responsiveness with baseline T PH and CD4 + T cell numbers highlights a role for T helper activity in B cell differentiation into antibody secreting cells during vaccine response.

7.
J Racial Ethn Health Disparities ; 5(4): 885-893, 2018 08.
Article in English | MEDLINE | ID: mdl-29124683

ABSTRACT

Past drug epidemics have disproportionately criminalized drug addiction among African Americans, leading to disparate health outcomes, increased rates of HIV/AIDS, and mass incarceration. Conversely, the current opioid addiction crisis in the USA focuses primarily on white communities and is being addressed as a public health problem. The 21st Century Cures Act has the potential to reduce racial health disparities in the criminal justice system through the Act's public health approach to addiction and mental health issues. The 21st Century Cures Act is a progressive step in the right direction; however, given the historical context of segregation and the criminalization of drug addiction among African Americans, the goals of health equity are at risk of being compromised. This paper discusses the implications of this landmark legislation and its potential to decrease racial health disparities, highlighting the importance of ensuring that access to treatment and alternatives to incarceration must include communities of color. In this paper, the authors explain the key components of the 21st Century Cures Act that are specific to criminal justice reform, including a key objective, which is treatment over incarceration. We suggest that without proper attention to how, and where, funding mechanisms are distributed, the 21st Century Cures Act has the potential to increase racial health disparities rather than alleviate them.


Subject(s)
Healthcare Disparities/legislation & jurisprudence , Mental Disorders/therapy , Mental Health/legislation & jurisprudence , Prisoners/legislation & jurisprudence , Public Health/legislation & jurisprudence , Racism/legislation & jurisprudence , Substance-Related Disorders/therapy , Adult , Aged , Criminal Law , Female , Humans , Male , Middle Aged , United States
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