Development of a recombinant VP2 vaccine for the prevention of novel variant strains of infectious bursal disease virus.

Since 2017, novel variant strains of infectious bursal disease virus (nvIBDV) have been detected in China, while the current vaccines on the market against very virulent IBDV have limited protection against this subtype virus. In this context, a strain of the virus has been isolated, and sequencing alignment and bird regression experiments showed that the virus was IBDV, belonging to the nvIBDV subtype (and named IBDV FJ-1812). Furthermore, the Escherichia coli expression system was used to successfully express soluble nvIBDV rVP2, which is specifically recognized by an anti-IBDV standard serum and anti-nvIBDV positive serum, and could be assembled into 14 - 17 nm virus-like particles. Based on the purified nvIBDV rVP2, we developed an IBDV FJ-1812 VP2 VLP vaccine at a laboratory scale to evaluate protection by this vaccine; in addition, we also prepared an IBDV JZ 3/02 VP2 subunit vaccine targeting very virulent IBDV and evaluated its cross-protection against nvIBDV. Results of bird experiments showed that the nvIBDV rVP2 vaccine could induce high titres of specific antibodies, completely protect the bursa of Fabricius from viral infection, and provide 100% immune protection to SPF and Ross 308 broiler chickens. Furthermore, the IBDV JZ 3/02 VP2 subunit vaccine targeting very virulent IBDV could provide 60% protection for SPF chickens and 80% protection for Ross 308 broiler chickens. This report provides important technical supports for the prevention and control of nvIBDV in the future.

Decreased expression of LKB1 is associated with epithelial-mesenchymal transition and led to an unfavorable prognosis in gastric cancer.

Liver kinase B1 (LKB1) is a newly discovered tumor suppressor gene that plays a role in tumorigenesis and cancer progression. However, LKB1 expression and its precise impact on gastric cancer (GC) have not yet been elucidated. The aim of this study was to explore the significance of LKB1 expression, as well as its correlation with epithelial-mesenchymal transition (EMT) in GC. In the present study, LKB1 protein was detected in 107 GC tissue samples and adjacent paracancerous tissues by immunohistochemical staining. The relationship of LKB1 expression with clinicopathological features and its correlation with 3 EMT-related markers (E-cadherin, ß-catenin, and vimentin) in GC were analyzed. Results revealed that the expression of LKB1 was decreased in GC tissues compared with that in adjacent paracancerous tissues (P = .005). GC patients with greater invasion depth (P = .007), higher pathological TNM stage (P = .014), and lymph node metastasis (P = .026) showed lower LKB1 expression; furthermore, E-cadherin and ß-catenin expression decreased, whereas vimentin expression increased (all P < .05). Kaplan-Meier analysis indicated that the expression of LKB1, E-cadherin, ß-catenin, and vimentin, as well as differentiation, invasion, pathological TNM, and lymph node metastasis, was associated with disease-free survival (DFS) (all P < .05). Multivariate analysis also showed that LKB1 expression (hazard ratio, 0.578 [0.351-0.950]; P = .031) may be an independent factor for DFS. In conclusion, LKB1 expression was decreased in GC, and this positively correlated with EMT and a shorter DFS, suggesting that LKB1 could act as an independent factor in predicting GC progression.

[Clinico-pathologic Analysis of 16 Cases of Castleman].

OBJECTIVE: To investigate the clinico-pathologic features, treatment and prognosis of Castleman disease. METHODS: The clinico-pathologic data of 16 patients diagnosed as Castleman disease from January 2002 to December 2014 were analyzed retrospectively. RESULTS: The median age was 28.5 (7-73)years old. There were 14 unicentric cases, 92.8% (13/14) of which was diagnosed as hyaline-vascular type. Two multicentric cases was diagnosed as plasmatcyic type. All the patients were treated by surgical resection and their median follow-up was 55.5 (2-150)months. As a result, 13 unicentric cases achieved sustained remission, 1 unicentric case with plasmatocytic type relapsed at 60th month after surgical resection. CONCLUSION: Clinical subtype and histopathogenic type are the dominating progonostic factors in Castleman patients. The clinical presentation of unicentric disease has been found to be benigns and the surgical resection can be used as first-line treatment method in clinic. The clinical presentation of multicentric disease may be stable or advanced, and the prognosis of advanced cases is poor as there are no effective treatments.