Objective:To explore the consistency of claudin 18.2 immunohistochemistry (IHC) using 4 different clone antibodies in gastric adenocarcinoma.Methods:A total of 226 gastric adenocarcinomas diagnosed and treated at the Drum Tower Hospital Affiliated to Nanjing University Medical College between January 2022 to March 2023 were included in this study. The cohort consisted of 165 males and 61 females, with a mean age of (61.3±12.1) years. Tumor tissues from radical resection specimens were collected for tissue microarrays. IHC detection of claudin 18.2 was performed using the EnVision method, utilizing 4 clones of antibody: OTIR157B5, 43-14A, EPR19202 and D313D22. The results were interpreted based on both the intensity of staining on tumor cell membranes and the percentage of positive tumor cells relative to the total tumor cells.Results:The positive cutoff value was set as moderately to strongly linear membrane staining in ≥75% of all viable invasive tumor cells, and clone OTIR157B5 demonstrated the highest positive expression rate at 52.2% (118/226). Additionally, the clones OTIR157B5, 43-14A, and EPR19202 were consistently and strongly positive, with all agreement rates of Cohen κ exceeding 0.8. In gastric adenocarcinoma and its three Lauren subtypes, OTIR157B5 exhibited clear membranous localization.Conclusions:Clone OTIR157B5 of claudin 18.2 antibody shows the highest rate of moderately to strongly linear membrane-positive staining, accounting for ≥75% of all viable invasive tumor cells, and clones 43-14A and EPR19202 show strong consistency and high sensitivity.

Probiotics are natural systems bridging synthetic biology, physical biotechnology, and immunology, initiating innate and adaptive anti-tumor immune activity. We previously constructed an all-in-one engineered food-grade probiotic Lactococcus lactis (FOLactis) which could boost the crosstalk among different immune cells such as dendritic cells (DCs), natural killer cells, and T cells. Herein, considering the limited clinical efficacy of naked personalized neoantigen peptide vaccines, we decorate FOLactis with tumor antigens by employing a Plug-and-Display system comprising membrane-inserted peptides. Intranodal injection of FOLactis coated with neoantigen peptides (Ag-FOLactis) induces robust DCs presentation and neoantigen-specific cellular immunity. Notably, Ag-FOLactis not only triggers a 45-fold rise in the quantity of locally reactive neoantigen-specific T cells but also induces epitope spreading in both subcutaneous and metastatic tumor-bearing models, leading to potent inhibition of tumor growth. These findings imply that Ag-FOLactis represents a powerful platform to rapidly and easily display antigens, facilitating the development of a bio-activated platform for personalized therapy.

Objective:To explore the consistency of claudin 18.2 immunohistochemistry (IHC) using 4 different clone antibodies in gastric adenocarcinoma.Methods:A total of 226 gastric adenocarcinomas diagnosed and treated at the Drum Tower Hospital Affiliated to Nanjing University Medical College between January 2022 to March 2023 were included in this study. The cohort consisted of 165 males and 61 females, with a mean age of (61.3±12.1) years. Tumor tissues from radical resection specimens were collected for tissue microarrays. IHC detection of claudin 18.2 was performed using the EnVision method, utilizing 4 clones of antibody: OTIR157B5, 43-14A, EPR19202 and D313D22. The results were interpreted based on both the intensity of staining on tumor cell membranes and the percentage of positive tumor cells relative to the total tumor cells.Results:The positive cutoff value was set as moderately to strongly linear membrane staining in ≥75% of all viable invasive tumor cells, and clone OTIR157B5 demonstrated the highest positive expression rate at 52.2% (118/226). Additionally, the clones OTIR157B5, 43-14A, and EPR19202 were consistently and strongly positive, with all agreement rates of Cohen κ exceeding 0.8. In gastric adenocarcinoma and its three Lauren subtypes, OTIR157B5 exhibited clear membranous localization.Conclusions:Clone OTIR157B5 of claudin 18.2 antibody shows the highest rate of moderately to strongly linear membrane-positive staining, accounting for ≥75% of all viable invasive tumor cells, and clones 43-14A and EPR19202 show strong consistency and high sensitivity.