[The impact of modified T3 sub-staging on the prognosis of gallbladder cancer patients]

Objective: To explore the value of a new modified T3 sub-staging for the prognosis evaluation in gallbladder cancer patients. Methods: This is a retrospective case-series study. The clinical data of patients with pathologically confirmed stage T3 gallbladder cancer who were admitted to the Department of Hepatobiliary Surgery,the First Affiliated Hospital of Xi'an Jiaotong University from January 2011 to December 2021 were retrospectively analyzed. A total of 190 patients were enrolled in this study, 67 males and 123 females, with an age (M(IQR)) of 63(14) years (range:17 to 88 years). The stage T3 was divided into four sub-stages according to the site of tumor invasion: (1) T3a:tumor perforates the serosa,but not invading the liver and one other adjacent structure; (2) T3b:tumor perforates the serosa and invades one other adjacent structure,but not the liver; (3) T3c:tumor perforates the serosa and invades the liver,but not one other adjacent structure; (4) T3d:tumor perforates the serosa,invades the liver and one other adjacent structure. To evaluate the application value of this modified sub-staging,the Kaplan-Meier method was used to draw the survival curve,univariate analysis and multivariate analysis were done using the Log-rank test and Cox proportional hazard model respectively. Results: According to the modified T3 sub-staging method,34 patients (17.9%) were in stage T3a,24 cases(12.6%) were in stage T3b, 97 cases (51.1%) were in stage T3c, and 35 cases (18.4%) were in stage T3d. The median survival time of patients in stages T3a,T3b,T3c and T3d after radical resection was 72.0 months, 32.0 months, 12.0 months and 10.0 months, respectively. The 1-, 3-, and 5-year survival rates of patients in stage T3a, T3b, T3c and T3d were 79.4%, 53.3%, and 53.3%; 79.2%, 44.6%, and 26.0%;49.5%,27.5%,and 18.1%;42.9%,15.9%, and 15.9% (χ2=18.349,P<0.01),respectively. Univariate analysis showed that gallbladder stones,pathological differentiation,perineural invasion, N stage,postoperative adjuvant therapy and modified T3 substage were factors affecting patient prognosis(all P<0.05). Cox multivariate analysis showed that modified sub-stages with T3c (HR=2.043, 95%CI:1.176 to 3.549) and T3d(HR=2.419, 95%CI:1.284 to 4.555), accompanied by gallbladder stones (HR=1.661,95%CI:1.150 to 2.398),pathological differentiation with poorly differentiated(HR=1.709,95%CI:1.198 to 2.438), and the N stage with N1 and N2(HR=1.602, 95%CI:1.090 to 2.355, 2.714, 95%CI: 1.621 to 4.544) were independent prognostic risk factors for patients in stage T3,while postoperative adjuvant chemotherapy(HR=0.351) was a protective factor for prognosis. There was no statistically significant difference in survival between patients with stage T3a and T3b who underwent hepatic wedge resection and liver segment or major resection (P=0.402). For patients with stage T3c and T3d with liver invasion,the survival difference after hepatic wedge resection and segmental or major resection was statistically significant (P=0.008). Conclusion: The modified T3 sub-staging system based on the depth and direction of tumor invasion maybe helpful to further stratify the prognosis of patients with gallbladder cancer.

[Analysis of perineural invasion with clinicopathological factors and prognosis for curatively resected gallbladder carcinoma]

Objective: To examine the correlation between perineural invasion and clinicopathological factors and the role of perineural invasion on the prognosis of patients with curatively resected gallbladder carcinoma. Methods: The clinicopathological and follow-up data of 548 patients with gallbladder carcinoma who underwent radical surgery from the First Affiliated Hospital of Xi'an Jiaotong University from January 2013 to December 2020 were analyzed retrospectively. There were 173 males and 375 females,with age(M(IQR)) of 62(14)years(range:30 to 88 years). The correlations between perineural invasion and the clinicopathological features were analyzed. The relationship between prognosis and clinicopathological factors were further analyzed. The survival curve was drawn using the Kaplan-Meier method. The univariate analysis and multivariate analysis were done using the Log-rank test and Cox proportional hazard model respectively. Results: Radical resection was performed in 548 cases,including 59 cases(10.8%) with perineural invasion. The results of univariate analysis showed that perineural invasion was related to serum bilirubin level,serum carcinoembryonic antigen(CEA) level,CA19-9 level,T stage,lymph node metastasis,liver invasion,vessel invasion and tumor location(all P<0.05).The results of multivariate analysis showed that jaundice,high-level serum CA19-9,high-level serum CEA,T4 stage,vessel invasion and tumor located in the neck or cystic duct of the gallbladder were independent risk factors of perineural invasion in gallbladder carcinoma. Survival of 367 patients in T3-T4 stages were analyzed. The prognosis of gallbladder carcinoma patients with perineural invasion was significantly worse than that of patients without perineural invasion(median survival time:12.0 months vs. 34.7 months,P<0.01). Univariate analysis showed that perineural invasion,gallbladder stones,gallbladder polyps,CA125,CEA,CA19-9,serum bilirubin level,tumor location,N stage,liver invasion and pathological differentiation were independent risk factors affecting prognosis of patients with gallbladder carcinoma(all P<0.05). The results of Cox proportional hazard model showed that perineural invasion,N stage,liver invasion,gallbladder stones,pathological differentiation were independent risk factors affecting prognosis of patients with gallbladder carcinoma(all P<0.05). Conclusions: Jaundice,high-level serum CA19-9,high-level serum CEA,T4 stage,vessel invasion and tumor located in the neck or cystic duct of the gallbladder are independent risk factors for perineural invasion of gallbladder carcinoma. Perineural invasion is one of the independent risk factors affecting the prognosis of T3-T4 stage gallbladder carcinoma.

Molecular cloning and characterization of a novel peptidase from Trichinella spiralis and protective immunity elicited by the peptidase in BALB/c mice

In our previous studies, a novel T. spiralis peptidase (TsP) was identified among the excretory/secretory (ES) proteins of T. spiralis intestinal infective larvae (IIL) and T. spiralis at the adult worm (AW) stage using immunoproteomics, but the biological function of TsP in the life cycle of T. spiralis is not clear. The objective of this study was to investigate the biological properties and functions of TsP in larval intrusion and protective immunity induced by immunization with rTsP. The complete TsP cDNA sequence was cloned and expressed. The results of RT-PCR, indirect immunofluorescence assay (IIFA) and western blotting revealed that TsP is a surface and secretory protein expressed in T. spiralis at different stages (muscle larvae, IIL, AWs and newborn larvae) that is principally localized at the epicuticle of the nematode. rTsP facilitated the larval intrusion of intestinal epithelial cells (IECs) and intestinal mucosa, whereas anti-rTsP antibodies suppressed larval intrusion; these facilitative and suppressive roles were dose-dependently related to rTsP or anti-rTsP antibodies. Immunization of mice with rTsP triggered an obvious humoral immune response (high levels of IgG, IgG1/IgG2a, and sIgA) and also elicited systemic (spleen) and intestinal local mucosal (mesenteric lymph node) cellular immune responses, as demonstrated by an evident increase in the cytokines IFN-γ and IL-4. Immunization of mice with rTsP reduced the numbers of intestinal adult worms by 38.6% and muscle larvae by 41.93%. These results demonstrate that TsP plays a vital role in the intrusion, development and survival of T. spiralis in hosts and is a promising candidate target molecule for anti-Trichinella vaccines.

Vaccination of mice with a recombinant novel cathepsin B inhibits Trichinella spiralis development, reduces the fecundity and worm burden

BACKGROUND

Trichinella spiralis is a major zoonotic tissue-dwelling nematode, which is a public health concern and a serious hazard to animal food safety. It is necessary to exploit an anti-Trichinella vaccine to interrupt the transmission of Trichinella infection among animals and from animals to humans. The purpose of the present study was to characterize the novel T. spiralis cathepsin B (TsCB) and to evaluate the immune protection elicited by immunization with recombinant TsCB (rTsCB).

METHODS

The complete cDNA sequences of the TsCB gene were cloned, expressed and purified. The antigenicity of rTsCB was investigated by western blot analysis and ELISA. Transcription and expression of TsCB at various T. spiralis life-cycle stages were analyzed by RT-PCR and indirect immunofluorescent assay (IIFA). The mice were subcutaneously immunized with rTsCB, and serum level of TsCB-specific IgG (IgG1 and IgG2a) and IgE antibodies were assayed by ELISA. Immune protection elicited by vaccination with rTsCB was investigated.

RESULTS

The TsCB was transcribed and expressed in four T. spiralis life-cycle stages (adult worm, AW; newborn larvae, NBL; muscle larvae, ML; and intestinal infective L1 larvae), it was primarily located in the cuticle and stichosome of the parasitic nematode. Vaccination of mice with rTsCB produced a prominent antibody response (high level of specific IgG and IgE) and immune protection, as demonstrated by a 52.81% AW burden reduction of intestines at six days post-infection (dpi) and a 50.90% ML burden reduction of muscles at 35 dpi after oral larva challenge. The TsCB-specific antibody response elicited by immunization with rTsCB also impeded intestinal worm growth and decreased the female fecundity.

CONCLUSIONS

TsCB might be considered as a novel potential molecular target to develop vaccines against T. spiralis infection.

Primary assessment of a T. spiralis putative serine protease for early serological detection of experimental trichinellosis

A putative serine protease of T. spiralis (TsSP) was expressed in Escherichia coli and its potential as a diagnostic antigen was primarily assessed in this study. Anti-Trichinella IgG in serum samples from T. spiralis different animal hosts (mice, rats, pigs and rabbits) were detected on Western blot analysis with rTsSP. Anti-Trichinella antibodies were detected in 100% (30/30) of experimentally infected mice by rTsSP-ELISA. Cross-reactions of rTsSPELISA were not found with sera from mice infected with other parasites (S. erinaceieuropaei, S. japonicum, C. sinensis, A. cantonensis and T. gondii) and sera from normal mice. There was no statistical difference in antibody detection rate among mice infected with the encapsulated Trichinella species (T. spiralis, T. nativa, T. britovi, and T. nelsoni) (P>0.05). The results of rTsSP-ELISA showed that serum specific antibody IgG in mice infected with 100 or 500 T. spiralis muscle larvae (ML) were detectable early at 7-8 dpi, but not detected by ML ES antigen-ELISA prior to 10-12 dpi. Specific anti-Trichinella IgG was detected in 100% (18/18) of infected pigs by rTsSP-ELISA and ES-ELISA, but no specific antibodies was not detected in 20 conventionally raised normal pigs by two antigens. The results showed the rTsSP had the potential for early serodiagnosis of animal Trichinella infection, however it requires to be assayed with early infection sera of swine infected with Trichinella and other parasites.

Intranasal immunization with recombinant Trichinella spiralis serine protease elicits protective immunity in BALB/c mice

The aim of this study was to observe the intestinal mucosal/systemic responses triggered by intranasal vaccination using recombinant Trichinella spiralis serine protease (rTsSP) and its capacity to elicit immune protection against larva challenge in a murine model. rTsSP coupled with cholera toxin B subunit (CTB) was used to vaccinate mice via intranasal route. The results revealed that intranasal vaccination with rTsSP plus CTB elicited significantly intestinal local sIgA response and a TsSP-specific systemic antibody response in vaccinated mice. Furthermore, more goblet cells/acidic mucins and IgA-secreting cells were observed in jejunum from vaccinated mice. Anti-rTsSP immune serum strongly recognized the cuticle of various worm stages (muscle larva, intestinal infective larva and adult worm). The level of IFN-γ, IL-4 and IL-10 of rTsSP-vaccinated mice was significantly elevated relative to CTB and PBS control groups. The vaccinated mice exhibited a 71.10% adult reduction at 9 days pi and a 62.10% muscle larva reduction at 42 days pi following larva challenge. Additionally, vaccination with rTsSP also dampened intestinal T. spiralis development and decreased the female fecundity. Our results showed that intranasal vaccination using rTsSP adjuvanted with CTB triggered significantly local sIgA response and systemic concurrent Th1/Th2 response that induced an obvious protection against Trichinella infection.

Protective immunity against Trichinella spiralis in mice elicited by oral vaccination with attenuated Salmonella-delivered TsSP1.2 DNA

Trichinellosis is a worldwide important food-borne zoonosis caused mainly by ingesting raw or undercooked pork infected with Trichinella spiralis larvae. The development of vaccine is needed for preventing swine from Trichinella infection to ensure pork safety. Previous studies showed that T. spiralis serine protease 1.2 (TsSP1.2) is a vaccine candidate against Trichinella infection. In this study, the complete TsSP1.2 cDNA sequences were cloned into pcDNA3.1, and the rTsSP1.2 DNA was transformed into attenuated Salmonella typhimurium strain ΔcyaSL1344. Oral vaccination of mice with Salmonella-delivered rTsSP1.2 DNA vaccine induced an obvious intestinal mucosal IgA response and a systemic Th1/Th2 immune response; the vaccinated mice showed a 33.45% reduction of intestinal adult worms and 71.84% reduction of muscle larvae after T. spiralis larval challenge. The protection might be due to the rTsSP1.2-induced production of specific anti-TsSP1.2 sIgA, IgG, IgG1/IgG2a, and secretion of IFN-γ, IL-4 and IL-10, which protected intestinal mucosa from the parasite invasion, inhibited worm development and reduced female fecundity. The results indicate that the attenuated Salmonella-delivered rTsSP1.2 DNA vaccine offers a prospective strategy for the prevention and control of animal Trichinella infection.

Shift in speed selectivity of visual cortical neurons: a neural basis of perceived motion contrast

The perceived speed of motion in one part of the visual field is influenced by the speed of motion in its surrounding fields. Little is known about the cellular mechanisms causing this phenomenon. Recordings from mammalian visual cortex revealed that speed preference of the cortical cells could be changed by displaying a contrast speed in the field surrounding the cell's classical receptive field. The neuron's selectivity shifted to prefer faster speed if the contextual surround motion was set at a relatively lower speed, and vice versa. These specific center-surround interactions may underlie the perceptual enhancement of speed contrast between adjacent fields.