[Preliminary evaluation of immunogenicity and protective effect of multicomponent recombinant protein vaccine EPRHP014 against tuberculosis]

Objective: To evaluate the immunogenicity and protective effect of a multicomponent recombinant protein vaccine EPRHP014 constructed independently and provide a scientific basis for developing new tuberculosis (TB) vaccine and effective prevention and control of TB. Methods: Three full-length Mycobacterium (M.) tuberculosis protein antigens (EsxH, Rv2628, and HspX) and two epitope-predicted and optimized epitope-dominant protein antigens (nPPE18 and nPstS1) were selected, from which five protein antigens were used to construct a protein antigen composition EPRHP014, including a fusion expression multi-component protein antigen (EPRHP014f) and a multi-component mixed protein antigen (EPRHP014m) formed with the five single protein using clone, purification, and purification respectively. Multicomponent protein vaccines EPRHP014f and EPRHP014m were prepared with aluminum adjuvant, and the BCG vaccine was used as a control. ELISA detected the titer of serum-specific antibodies, the secretion of various cytokines was detected by ELISpot and Luminex, and immune protection was observed by the M. tuberculosis growth inhibition test in vitro. The results were statistically analyzed by t-test or rank sum test, and P<0.05 was considered a statistically significant difference. Results: Mice Immunized with EPRHP014m and EPRHP014f could produce highly effective IgG antibodies and their subtypes IgG1 and IgG2a, and the antibody titers were similar to those of mice immunized with BCG, with no statistical significance (P>0.05). The number of spot-forming cells (SFC) secreting IFN-γ and IL-4 induced by EPRHP014f group was significantly higher than those by EPRHP014m group and BCG group (P<0.05), but there was no significant difference in the number of SFC for IFN-γ and IL-4 induced between EPRHP014m group and BCG group (P>0.05). The secretion levels of GM-CSF and IL-12p70 induced by the EPRHP014m group were higher than those of the BCG group (P<0.05), but there was no significant difference in the levels of IL-6 and IL-10 induced between EPRHP014m group and BCG group (P>0.05). There was no significant difference in the secretions of IL-6, IL-10, IL-12, and GM-CSF between the EPRHP014f and BCG groups (P>0.05). EPRHP014m group, EPRHP014f group, and BCG group had obvious antibacterial effects in vitro, and the difference was insignificant (P>0.05). Conclusion: Both EPRHP014f and EPRHP014m can induce strong humoral and cellular immune responses in mice after immunization, and have a strong ability to inhibit the growth of M. tuberculosis in vitro, indicating that the antigen composition EPRHP014 has good potential in the development and application of TB vaccine.

[Seroprevalence of Toxoplasma gondii infections among patients with autoimmune diseases]

OBJECTIVE

To understand the seroprevalence of Toxoplasma gondii infections among patients with autoimmune diseases, so as to provide the scientific evidence for the management of toxoplasmosis in patients with autoimmune diseases.

METHODS

A total of 237 patients with definitive diagnosis of autoimmune disease were selected as the study subjects, including 79 cases with systemic lupus erythematosus, 71 cases with rheumatoid arthritis and 87 cases with inflammatory bowel disease, while 237 healthy volunteers served as controls. The serum anti-T. gondii IgG antibody was detected using enzyme-linked immunosorbent assay (ELISA) in patients with autoimmune diseases and healthy controls, and the detection of serum IgG antibody against T. gondii was compared between the autoimmune disease patients and healthy controls.

RESULTS

The seroprevalence of serum IgG antibody against T. gondii was significantly greater in patients with autoimmune diseases than in healthy controls (29.96% vs. 4.22%; χ² = 55.41, P < 0.01), and the seroprevalence of T. gondii infection was all significantly higher in patients with systemic lupus erythematosus (31.65%), rheumatoid arthritis (23.94%) and inflammatory bowel disease (33.33%) than in healthy controls (χ² = 45.25, 26.58 and 50.95; all P values < 0.01).

CONCLUSIONS

The seroprevalence of anti-T. gondii IgG antibody is significantly higher in patients with autoimmune diseases than in healthy controls, and T. gondii infection may be a potential risk factor for the development of systemic lupus erythematosus, rheumatoid arthritis and inflammatory bowel disease.

[Seroprevalence of Toxoplasma gondii and Toxocara infections among pregnant women in Hangzhou City]

OBJECTIVE

To investigate the prevalence of Toxoplasma gondii and Toxocara infections among pregnant women in Hangzhou City, so as to provide baseline data for decreasing birth defects and improving the population quality.

METHODS

A total of 235 pregnant women receiving prenatal diagnosis at the First People's Hospital of Yuhang District during the period between February 2018 through December 2019 were recruited as the observation group, and 235 age-matched, non-pregnant healthy women at the same hospital during the same period served as the control group. The subjects'medical records were captured from the hospital management information system. Blood samples were collected from the observation and control groups and detected for the presence of IgG antibodies against T. gondii and Toxocara using an enzyme-linked immunosorbent assay (ELISA). The seroprevalence of the IgG antibodies against T. gondii and Toxocara was compared between the observation and control groups.

RESULTS

The subjects in the observation group had a mean age of 26.5 ± 4.3 years (range, 23 to 31 years), and gestational ages of 10 to 27 weeks, and the subjects in the control group had a mean age of 26.1 ± 5.7 years (range, 20 to 30 years). The seroprevalence rates of IgG antibodies against T. gondii (28.51% vs. 4.68%; χ² = 34.85, P < 0.01) and Toxocara (24.26% vs. 5.11%; χ² = 25.77, P < 0.01) were both significantly higher in the observation group than in the control group, and the seroprevalence of T. gondii and Toxocara co-infections was also significantly greater in the observation group than in the control group (13.19% vs. 2.13%; χ² = 17.49, P < 0.01).

CONCLUSIONS

The seroprevalence rates of T. gondii and Toxocara infections and their co-infections are all high among pregnant women in Hangzhou City. Screening of T. gondii and Toxocara infections is strongly recommended during pregnancy.

[Clinical study of perioperative changes in plasma potassium]

Forty adult patients undergoing non-cardiac major surgery were divided into 2 groups. Group A (n = 20) was anesthetized by balanced intravenous procaine anesthesia and group B (n = 20) by epidural block. Blood volume, urine output, potassium in plasma as well as urine, pH, glucose, aldosterone, cortisol and insulin were measured from 24 hours before operation to 48 hours after operation. Evident perioperative trend of hypokalemia in patients with normal renal function was most likely due to the following factors: potassium loss prior to operation, improper pre- or post-operative replacement of fluids, perioperative stress, increasing of blood insulin and urine potassium excretion. Our results run against to the general concept that it may not be necessary to supply potassium with 72 hours after operation.