A sensitive and convenient enzyme-linked immunosorbent assay method in serum MG7 antigen detection in gastric cancer

Objective To explore a highly sensitive and highly specific method to detect the serum MG7 antigen(Ag)level for early gastric cancer diagnosis.Methods The serum MG7-Ag level was detected by enzyme-linked immunosorbent assay(ELISA)method in 116 preoperative gastric cancer patients,63 postoperative gastric cancer patients,41 patients with precancerous lesion,37 pa-

Anti-enrofloxacin Antibody Production by Using Enrofloxacin-screened HSA as an Immunogen

A two-step zero-length cross-linking procedure using active esters was successfully adopted for conjugating en-rofloxacin (EF) to human serum albumin (HSA). The derived conjugate was characterized by UV spectrum and then usedfor immunization of BALB/C mice. In enzyme-linked immunosorbent assay (ELISA) and competitive inhibition ELISA ex-periments, the derived antiserum exhibited high antibody titer (greater than 1: 250 000) as well as varied cross-reactivity(from 97.8% to 161.7%) to three analogs of EF belonging to fluoroquinolones family. But over the concentration rangestudied, no significant cross-reactivity was observed to other group of antibiotics (chloramphenicol, oxytetracycline, sul-phamethoxazole and nysfungin). It was confirmed that the synthesized immunogen was highly antigenic and elicited specificantibody responses in BALB/C mice against EF.

Canine Herpesvirus Seroprevalence and Associated Factors in Dogs of Mexico

Canine herpesvirus (CHV-1) causes disease associated with high mortality in infect-ed puppies, which represents large financial losses for dog breeders. Since CHV-1 at the time of the study he had not been reported in Mexico, the main objective of this study was to determine the prevalence of antibodies against CHV-1 in canine kennels in the metropolitan area of Mexico City. A commercial enzyme-linked immuno-sorbent assay (ELISA) was used, and the results were compared to those of a viral neutralization test. The ELISA kit uses the complete viral particle as the antigen. The plaque reduction neutralization test was combined with the immunoperoxidase technique because of the low cytopathic effect of CHV-1. Neutralizing antibodies were also detected in 20 randomly selected samples. The prevalence of CHV-1 with ELISA was 87%. The concordance between ELISA and serum neutralization (SN) was 0.1129, the sensitivity of the ELISA against SN was 1.0 (100%), the positive predic-tive value was 0.39 (39%), and the negative predictive value was 1 (100%). These results show that ELISA is useful for monitoring the dog population for CHV-1;a positive test result requires confirmation with an SN test, and a negative ELISA result indicates a high probability of being SN-negative. The only variables that were sta-tistically associated with CHV-1 prevalence were breed and kennel. A statistically significant relationship between the degree of ELISA and SN titer was obtained, with a confidence level of 95%. None of the clinical presentation factors was statistically significant. These results suggest that most of the canine population studied in Mex-ico is in a herpesvirus latency state.

Serum semaphorin 4C as a diagnostic biomarker in breast cancer:A multicenter retrospective study

Background:To date,there is no approved blood-based biomarker for breast cancer detection.Herein,we aimed to assess semaphorin 4C(SEMA4C),a pivotal protein involved in breast cancer progression,as a serum diagnostic biomarker.Methods:We included 6,213 consecutive inpatients from Tongji Hospital,Qilu Hospital,and Hubei Cancer Hospital.Training cohort and two validation cohorts were introduced for diagnostic exploration and validation.A pan-cancer cohort was used to independently explore the diagnostic potential of SEMA4C among solid tumors.Breast cancer patients who underwent mass excision prior to modified radical mastectomy were also analyzed.We hypothesized that increased pretreatment serum SEMA4C levels,measured using optimized in-house enzymelinked immunosorbent assay kits,could detect breast cancer.The endpoints were diagnostic performance,including area under the receiver operating characteristic curve(AUC),sensitivity,and specificity.Post-surgery pathological diagnosis was the reference standard and breast cancer staging followed the TNM classification.There was no restriction on disease stage for eligibilities.Results:We included 2667 inpatients with breast lesions,2378 patients with other solid tumors,and 1168 healthy participants.Specifically,118 patients with breast cancer were diagnosed with stage 0(5.71%),620 with stage I(30.00%),966 with stage II(46.73%),217 with stage III(10.50%),and 8 with stage IV(0.39%).Patients with breast cancer had significantly higher serum SEMA4C levels than benign breast tumor patients and normal controls(P<0.001).Elevated serum SEMA4C levels had AUC of 0.920(95%confidence interval[CI]:0.900–0.941)and 0.932(95%CI:0.911–0.953)for breast cancer detection in the two validation cohorts.The AUCs for detecting early-stage breast cancer(n=366)and ductal carcinoma in situ(n=85)were 0.931(95%CI:0.916–0.946)and 0.879(95%CI:0.832–0.925),respectively.Serum SEMA4C levels significantly decreased after surgery,and the reduction was more striking after modified radical mastectomy,compared with mass excision(P<0.001).The positive rate of enhanced serum SEMA4C levels was 84.77%for breast cancer and below 20.75%for the other 14 solid tumors.Conclusions:Serum SEMA4C demonstrated promising potential as a candidate biomarker for breast cancer diagnosis.However,validation in prospective settings and by other study groups is warranted.