ABSTRACT
The COVID-19 pandemic continues to impose a significant burden on global health infrastructure. While identification and containment of new cases remains important, laboratories must now pivot and consider assessment of SARS-CoV-2 immunity in the setting of the recent availability of multiple COVID-19 vaccines. Here we have utilized the latest Abbott Alinity semi-quantitative IgM and quantitative IgG spike protein (SP) serology assays (IgMSP and IgGSP) in combination with Abbott Alinity IgG nucleocapsid (NC) antibody test (IgGNC) to assess antibody responses in a cohort of 1236 unique participants comprised of naive, SARS-CoV-2 infected, and vaccinated (including both naive and recovered) individuals. The IgMSP and IgGSP assays were highly specific (100%) with no cross-reactivity to archived samples recovered prior to the emergence of SARS-CoV-2, including those from individuals with seasonal coronavirus infections. Clinical sensitivity was 96% after 15 days for both IgMSP and IgGSP assays individually. When considered together, the sensitivity was 100%. A combination of NC- and SP-specific serologic assays clearly differentiated naive, SARS-CoV-2-infected, and vaccine-related immune responses. Vaccination resulted in a significant increase in IgGSP and IgMSP titers, with a major rise in IgGSP following the booster (second) dose in the naive group. In contrast, SARS-CoV-2 recovered individuals had several fold higher IgGSP responses than naive following the primary dose, with a comparatively dampened response following the booster. This work illustrates the strong clinical performance of these new serological assays and their utility in evaluating and distinguishing serological responses to infection and vaccination.
ABSTRACT
Hepatocellular carcinoma (HCC) currently has the fifth highest incidence rate among tumors worldwide, a rate expected to continue to increase over the next several decades. The majority of patients with HCC have cirrhosis of the liver, with chronic hepatitis B and C as the major agents of etiology. Despite advances in technology, the prognosis of patients with HCC has shown little improvement over time, most likely because most patients are diagnosed at advanced stages. HCC meets the criteria established by the World Health Organization for performing surveillance in those at risk for developing this tumor (ie, patients with cirrhosis of the liver). The objective of surveillance is to use a relatively simple and inexpensive examination in a large number of individuals to determine whether or not they are likely to develop cancer, with the overall goal of reducing morbidity and mortality from the cancer. In this article, we evaluate the criteria for performing surveillance for HCC and review the data on the efficacy of current surveillance programs.
