Neutralizing antibody test supports booster strategy for young individuals after SARS-CoV-2 Omicron breakthrough.

Background: The SARS-CoV-2 Omicron variant, since its initial detection, has rapidly spread across the globe, becoming the dominant strain. It is important to study the immune response of SARS-CoV-2 Omicron variant due to its remarkable ability to escape the majority of existing SARS-CoV-2 neutralizing antibodies. The surge in SARS-CoV-2 Omicron infections among most Chinese residents by the end of 2022 provides a unique opportunity to understand immune system's response to Omicron in populations with limited exposure to prior SARS-CoV-2 variants.

FcRn-guided antigen trafficking enhances cancer vaccine efficacy.

The development of tumor vaccines represents a significant focus within cancer therapeutics research. Nonetheless, the efficiency of antigen presentation in tumor vaccine remains suboptimal. We introduce an innovative mRNA-lipid nanoparticle platform designed to express tumor antigenic epitopes fused with the transmembrane domain and cytoplasmic tail of the neonatal Fc receptor (FcRn).

A bispecific antibody targeting the Ig domains of Siglec-E displays enhanced antitumor effects.

Siglec-9 is a promising immune checkpoint molecule, and therapeutics targeting Siglec-9 have the potential to augment anti-tumor immunity. Here, we generated a bispecific antibody, named as aSE4-1-Fc, by fusing two distinct alpaca derived nanobodies, which can simultaneously target the extracellular Ig variable (V)-set domain and C2-set domains of murine Siglec-9 (also known as Siglec-E) with high affinity. In vivo studies showed that aSE4-1-Fc was better than its component antibodies in inhibiting tumor growth/metastasis, and Siglec-E blockade using aSE4-1-Fc generated protective anti-tumor T cell memory.

Antibody responses following the surge of SARS-CoV-2 Omicron infection among patients with systemic autoimmune rheumatic diseases.

Objectives: The surge of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant Omicron infections has affected most Chinese residents at the end of 2022, including a number of patients with systemic autoimmune rheumatic diseases (SARDs).

Methods: To investigate the antibody level of the Omicron variant in SARD patients after SARS-CoV-2 Omicron infection, we tested BA.5.