• Deep dissection of the antiviral immune profile of patients with COVID-19.

      Atanackovic, Djordje; Avila, Stephanie V; Lutfi, Forat; de Miguel-Perez, Diego; Fan, Xiaoxuan; Sanchez-Petitto, Gabriela; Vander Mause, Erica; Siglin, Jonathan; Baddley, John; Mannuel, Heather D; et al. (Springer Nature, 2021-12-16)
      In light of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants potentially undermining humoral immunity, it is important to understand the fine specificity of the antiviral antibodies. We screened 20 COVID-19 patients for antibodies against 9 different SARS-CoV-2 proteins observing responses against the spike (S) proteins, the receptor-binding domain (RBD), and the nucleocapsid (N) protein which were of the IgG1 and IgG3 subtypes. Importantly, mutations which typically occur in the B.1.351 "South African" variant, significantly reduced the binding of anti-RBD antibodies. Nine of 20 patients were critically ill and were considered high-risk (HR). These patients showed significantly higher levels of transforming growth factor beta (TGF-β) and myeloid-derived suppressor cells (MDSC), and lower levels of CD4+ T cells expressing LAG-3 compared to standard-risk (SR) patients. HR patients evidenced significantly higher anti-S1/RBD IgG antibody levels and an increased neutralizing activity. Importantly, a large proportion of S protein-specific antibodies were glycosylation-dependent and we identified a number of immunodominant linear epitopes within the S1 and N proteins. Findings derived from this study will not only help us to identify the most relevant component of the anti-SARS-CoV-2 humoral immune response but will also enable us to design more meaningful immunomonitoring methods for anti-COVID-19 vaccines.
    • Humoral immunity against SARS-CoV-2 variants including omicron in solid organ transplant recipients after three doses of a COVID-19 mRNA vaccine.

      Saharia, Kapil K; Husson, Jennifer S; Niederhaus, Silke V; Iraguha, Thierry; Avila, Stephanie V; Yoo, Youngchae J; Hardy, Nancy M; Fan, Xiaoxuan; Omili, Destiny; Crane, Alice; et al. (Wiley-Blackwell, 2022-04-29)
      Following the initial vaccination series, 60.3% of SOTR showed no measurable neutralisation and only 18.9% demonstrated neutralising activity of > 90%. More intensive immunosuppression, antimetabolites in particular, negatively impacted antiviral immunity. While absolute IgG levels were lower in SOTR than controls, antibody titres against microbial recall antigens were higher. By contrast, SOTR showed reduced vaccine-induced IgG/IgA antibody titres against SARS-CoV-2 and its delta variants and fewer linear B-cell epitopes, indicating reduced B-cell diversity. Importantly, a third vaccine dose led to an increase in anti-SARS-CoV-2 antibody titres and neutralising activity across alpha, beta and delta variants and to the induction of anti-SARS-CoV-2 CD4+ T cells in a subgroup of patients analysed. By contrast, we observed significantly lower antibody titres after the third dose with the omicron variant compared to the ancestral SARS-CoV-2 and the improvement in neutralising activity was much less pronounced than for all the other variants.
    • T cell responses against SARS-CoV-2 and its Omicron variant in a patient with B cell lymphoma after multiple doses of a COVID-19 mRNA vaccine

      Atanackovic, Djordje; Kreitman, Robert J; Cohen, Jeffrey; Hardy, Nancy M; Omili, Destiny; Iraguha, Thierry; Burbelo, Peter D; Gebru, Etse; Fan, Xiaoxuan; Baddley, John; et al. (BMJ, 2022-07-17)
      Anti-SARS-CoV-2 antibodies are crucial for protection from future COVID-19 infections, limiting disease severity, and control of viral transmission. While patients with the most common type of hematologic malignancy, B cell lymphoma, often develop insufficient antibody responses to messenger RNA (mRNA) vaccines, vaccine-induced T cells would have the potential to ‘rescue’ protective immunity in patients with B cell lymphoma. Here we report the case of a patient with B cell lymphoma with profound B cell depletion after initial chemoimmunotherapy who received a total of six doses of a COVID-19 mRNA vaccine. The patient developed vaccine-induced anti-SARS-CoV-2 antibodies only after the fifth and sixth doses of the vaccine once his B cells had started to recover. Remarkably, even in the context of severe treatment-induced suppression of the humoral immune system, the patient was able to mount virus-specific CD4+ and CD8+ responses that were much stronger than what would be expected in healthy subjects after two to three doses of a COVID-19 mRNA vaccine and which were even able to target the Omicron ‘immune escape’ variant of the SARS-CoV-2 virus. These findings not only have important implications for anti-COVID-19 vaccination strategies but also for future antitumor vaccines in patients with cancer with profound treatment-induced immunosuppression.
    • Vaccine-induced T-cell responses against SARS-CoV-2 and its Omicron variant in patients with B cell-depleted lymphoma after CART therapy.

      Atanackovic, Djordje; Luetkens, Tim; Omili, Destiny; Iraguha, Thierry; Lutfi, Forat; Hardy, Nancy M; Fan, Xiaoxuan; Avila, Stephanie V; Saharia, Kapil K; Husson, Jennifer S; et al. (Elsevier, 2022-07-14)