Critical design criteria for engineering a nanoparticulate HIV-1 vaccine

Inducing a long-lasting as well as broad and potent immune response by generating broadly neutralizing antibodies is a major goal and at the same time the main challenge of preventive HIV-1 vaccine design. Immunization with soluble, stabilized and native-like envelope (Env) glycoprotein so far only led to low neutralization breadth and displayed low immunogenicity. A promising approach to generate a potent immune response is the presentation of Env on the surface of nanoparticles. In this review, we will focus on two key processes essential for the induction of immune response that can be addressed by specific features of nanoparticulate carriers: first, the trafficking to and within distinct compartments of the lymph node, and second, the use of multivalent Env display allowing for high avidity interactions. To optimize these pivotal steps critical design criteria should be considered for the presentation of Env on nanoparticles. These include an optimal particle size below 100 nm, distances between two adjacent Env antigens of approximately 10-15 nm, an appropriate orientation of Env, and finally, the stability of both the Env attachment and the nanoparticle platform. Hence, an interdisciplinary approach that combines a suitable delivery system and a straightforward presentation of the Env antigen may have the potential to drive the immune response towards increased breadth and potency.

Three-year survival and distribution of lymph node metastases in gastric cancer following neoadjuvant chemotherapy: results from a European randomized clinical trial

BACKGROUND

Adequate lymphadenectomy is an important step in gastrectomy for cancer, with a modified D2 lymphadenectomy being recommended for advanced gastric cancers. When assessing a novel technique for the treatment of gastric cancer, lymphadenectomy should be non-inferior. The aim of this study was to assess completeness of lymphadenectomy and distribution patterns between open total gastrectomy (OTG) and minimally invasive total gastrectomy (MITG) in the era of peri-operative chemotherapy.

METHODS

This is a retrospective analysis of the STOMACH trial, a randomized clinical trial in thirteen hospitals in Europe. Patients were randomized between OTG and MITG for advanced gastric cancer after neoadjuvant chemotherapy. Three-year survival, number of resected lymph nodes, completeness of lymphadenectomy, and distribution patterns were examined.

RESULTS

A total of 96 patients were included in this trial and randomized between OTG (49 patients) and MITG (47 patients). No difference in 3-year survival was observed, this was 57.1% in OTG group versus 46.8% in MITG group (P = 0.186). The mean number of examined lymph nodes per patient was 44.3 ± 16.7 in the OTG group and 40.7 ± 16.3 in the MITG group (P = 0.209). D2 lymphadenectomy of 71.4% in the OTG group and 74.5% in the MITG group was performed according to the surgeons; according to the pathologist compliance to D2 lymphadenectomy was 30% in the OTG group and 36% in the MITG group. Tier 2 lymph node metastases (stations 7-12) were observed in 19.6% in the OTG group versus 43.5% in the MITG group (P = 0.024).

CONCLUSION

No difference in 3-year survival was observed between open and minimally invasive gastrectomy. No differences were observed for lymph node yield and type of lymphadenectomy. Adherence to D2 lymphadenectomy reported by the pathologist was markedly low.

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection

PURPOSE

Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial.

METHODS

Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups.

RESULTS

Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group.

CONCLUSION

LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.