Plant bioreactor is a new production platform for expression of recombinant protein, which is one of the cores of molecular farming. In this study, the anti DYKDDDDK (FLAG) antibody was recombinantly expressed in tobacco (Nicotiana benthamiana) and purified. FLAG antibody with high affinity was obtained after immunizing mice for several times and its sequence was determined. Based on this, virus vectors expressing heavy chain (HC) and light chain (LC) inoculated into Nicotiana benthamiana leaves by using Agrobacterium-mediated delivery. Accumulation of the HC and LC was analyzed by SDS/PAGE followed by Western blotting probed with specific antibodies from 2 to 9 days postinfiltration (dpi). Accumulation of the FLAG antibody displayed at 3 dpi, and reached a maximum at 5 dpi. It was estimated that 66 mg of antibody per kilogram of fresh leaves could be obtained. After separation and purification, the antibody was concentrated to 1 mg/mL. The 1:10 000 diluted antibody can probe with 1 ng/mL FLAG fused antigen well, indicating the high affinity of the FLAG antibody produced in plants. In conclusion, the plant bioreactor is able to produce high affinity FLAG antibodies, with the characteristics of simplicity, low cost and highly added value, which contains enormous potential for the rapid and abundant biosynthesis of antibodies.
Animals ; Mice ; Antibodies ; Nicotiana/genetics* ; Agrobacterium/genetics* ; Bioreactors ; Blotting, Western

Objective To prepare mouse monoclonal antibodies against the ectodomain of E2 (E2ecto) glycoprotein of Western equine encephalitis virus (WEEV). Methods A prokaryotic expression plasmid pET-28a-WEEV E2ecto was constructed and transformed into BL21 (DE3) competent cells. E2ecto protein was expressed by IPTG induction and presented mainly as inclusion bodies. Then the purified E2ecto protein was prepared by denaturation, renaturation and ultrafiltration. BALB/c mice were immunized with the formulated E2ecto protein using QuickAntibody-Mouse5W as an adjuvant via intramuscular route, boosted once at an interval of 21 days. At 35 days post-immunization, mice with antibody titer above 1×10⁴ were inoculated with E2ecto intraperitoneally, and spleen cells were fused with SP2/0 cells three days later. Hybridoma cells secreting specific monoclonal antibodies were screened by the limited dilution method, and ascites were prepared after intraperitoneal inoculation of hybridoma cells. The subtypes and titers of the antibodies in ascites were assayed by ELISA. The biological activity of the mAb was identified by immunofluorescence assay(IFA) on BHK-21 cells which were transfected with eukaryotic expression plasmid pCAGGS-WEEV-CE3E2E1. The specificity of the antibodies were evaluated with E2ecto proteins from EEEV and VEEV. Results Purified WEEV E2ecto protein was successfully expressed and obtained. Four monoclonal antibodies, 3G6G10, 3D7G2, 3B9E8 and 3D5B7, were prepared, and their subtypes were IgG2c(κ), IgM(κ), IgM(κ) and IgG1(κ), respectively. The titers of ascites antibodies 3G6G10, 3B9E8 and 3D7G2 were 10⁵, and 3D5B7 reached 10⁷. None of the four antibody strains cross-reacted with other encephalitis alphavirus such as VEEV and EEEV. Conclusion Four strains of mouse mAb specifically binding WEEV E2ecto are successfully prepared.
Horses ; Animals ; Mice ; Encephalitis Virus, Western Equine ; Ascites ; Immunosuppressive Agents ; Antibodies, Monoclonal ; Immunoglobulin M

Hypoglycemic disorders are rare in persons without diabetes, and clinical evaluation to identify its etiology can be challenging. We present a case of insulin autoimmune syndrome induced by carbimazole in a middle-aged Chinese man with underlying Graves’ disease, which was managed conservatively with a combination of dietary modification and alpha-glucosidase inhibitor.
Hypoglycemia ; Hyperinsulinism ; Insulin Antibodies

BACKGROUND

The Philippines is hyperendemic for hepatitis B infection. Vaccination is crucial for protection. Local data on the antibody response after completion of the primary vaccination series is limited.

This study aimed to measure the anti-HBs levels among college students who completed primary hepatitis B vaccination series, compare seropositivity across stratified groups and correlate anti-HBs levels with the time elapsed since the last vaccine dose.

This cross-sectional study included 111 college students in health-related courses with immunization record showing the complete primary Hepatitis B vaccination series. Participants were stratified based on the following vaccination schedules: 0-1-6-month group; 0-1-2-month group; and booster group. Anti-HBs titers were determined.

Statistical analyses included One-way ANOVA, Kruskal-Wallis test, Fisher’s Exact test and Shapiro-Wilk normality test. Kaplan-Meier Survival Estimate assessed the probability of anti-HBs seropositivity over time. Data were analyzed using STATA 13.1.

The baseline characteristics of the study population were homogenous. The median anti-HBs titer several years after primary vaccination was low at 2.9 mIU/mL. Participants in the booster group had the highest seropositivity rate (57.14%) with a median titer of 30.16 mIU/mL. There was an inverse relationship between anti-HBs titer and elapsed time since the last vaccine dose. Kaplan-Meier Survival Estimate showed that the seropositivity decreases to 90.56% after 15.8 years, 51.3% after 17.5 years, and 2.97% at 18 years.

This study revealed low anti-HBs titers among students who previously completed primary vaccination series, with no significant difference between two schedules. Booster doses resulted in the highest seropositivity. Over-all, seropositivity declines over time.

BACKGROUND

Pre-transfusion testing is done to avoid transfusion morbidity from unexpected RBC antibodies. Available commercial kits from Western brands may not consider racial differences in antibody frequencies between East/Southeast Asians and Western populations. The limited number of blood banks in the Philippines precludes research on RBC antibody screening and identification in the country.

This study aimed to compare RBC antibody screening and identification methods in patients at a tertiary hospital in the Philippines, assess the frequency of major blood group antibodies using both techniques, and review clinical histories of discrepant and nonspecific cases.

Retrospective review showed 118 cases with both screening and identification tests using both conventional tube-based technique and column agglutination or gel-based technique. Antibody frequencies and discrepant or nonspecific results were recorded. Concordance rates were calculated, and differences between the two methods were analyzed using 95% confidence interval (95% CI). Clinical histories of discrepant and nonspecific cases were also reviewed.

The most frequent major blood group was Rh (41 cases or 34.7%), followed by MNS (34 cases or 28.8%) and Kidd (15 cases or 12.7%). The most common antibody was Anti-E (24 cases or 20.3%), followed by Anti-Mia (19 cases or 16.1%), and Anti-M and Anti-c (12 cases each, or 10.2% each). The concordance rate for screening was statistically significant at 72%. Concordance rate for identification was 59.3%, with significant difference in identifying Anti-Mia. Clinical histories for discrepant or nonspecific cases showed previous transfusions, pregnancy, lymphoproliferative conditions, and certain medications.

Statistically significant differences between the two methods were found, with the gel-based technique identifying more Anti-Mia cases. Negative results from the tube-based method do not fully exclude Anti-Mia. These discrepancies highlight the benefit of using both methods for comprehensive RBC antibody screening and identification, done as a complement to the other.

Pemphigus is a rare, chronic, life-threatening autoimmune blistering disease characterized by blisters and erosions of the skin and mucous membranes. Rituximab has been approved as a first-line treatment for moderate to severe pemphigus vulgaris. Despite of its efficacy in achieving remission, Rituximab can also lead to serious complications such as Hepatitis B reactivation.

We present a case of a 42-year-old Filipino male with severe pemphigus vulgaris on chronic immunosuppressive therapy. He had a 10-month history of multiple bullae and crusted erosions associated with pruritus and burning pain on the mouth resulting to odynophagia and dysphagia. He is a known case of chronic Hepatitis B with unrecalled vaccination status. On physical examination, Nikolsky and Asboe-Hansen signs were positive. Histopathology show intraepidermal split and row of suprabasal keratinocytes pattern. ELISA showed very high levels (>200 RU/ml) for both anti-desmoglein 1 & 3. DIF was positive for IgG & C3. Prior to Rituximab administration, Tenofovir 300 mg/tab/day was started as pre-emptive therapy. To lessen the dependence on systemic corticosteroids, two infusions of Rituximab 1g 2 weeks apart were then given. Notable improvement was seen, evidenced by absence of new bullae, reduction of affected BSA, from 19% to 5.3% and decreased PDAI (78 to 1) and ABSIS (46.5 to 2.75) four months after treatment. Maintained remission and undetectable Hepatitis B viral load 4 months following the last dose of Rituximab were noted, indicating a positive treatment response to both Rituximab and Tenofovir.

Rituximab represents a viable treatment option even for patients with chronic Hepatitis B. Pre-emptive therapy may be done prior to infusion to prevent hepatitis reactivation. Clinical evidence supports the efficacy and safety of Rituximab in this case where preventive measures are taken.

Herpes zoster is a clinical syndrome associated with reactivation of varicella zoster virus (VZV), often occurring years after VZV infection, and characterized typically by painful grouped vesicles in a dermatomal distribution. Bullous herpes zoster, an atypical presentation of herpes zoster, is a relatively rare phenomenon; to the authors’ knowledge, there have only been eight reports in worldwide literature. We present a case of a 59-year-old female with lupus nephritis who presented with multiple grouped vesicles evolving into large tender bullae filled with serosanguinous fluid on the lateral aspect of the right leg, and dorsal and medial aspects of the right foot, four days after the first dose of 1g of rituximab therapy. The diagnosis of bullous herpes zoster along L4-L5 dermatomes was made based on the clinical presentation and the presence of multinucleated giant cells on Tzanck smear. The giant bullae were drained and dressed, and the patient was treated with valacyclovir at the renally adjusted dose of 1g once a day for seven days and pregabalin 150 mg once daily. After seven days of antiviral treatment, there were no new bullae or vesicles, and the pain improved. Recognizing this atypical presentation of a common disease, especially in patients with an immunocompromised state, highlights the importance of prompt recognition and treatment.
Human ; herpes zoster ; lupus nephritis ; rituximab ; diagnosis, differential

To observe the symptom control, pulmonary function changes and safety of use of omalizumab in patients with moderate to severe allergic asthma for 1 year. A small sample self-controlled study before and after treatment was conducted to retrospective analysis involved 17 patients with moderate to severe asthma who received omalizumab therapy for 12 months in Peking University People's Hospital and Beijing Jishuitan Hospital from January 2020 to December 2021. The clinical symptoms and pulmonary function changes were compared before treatment, after 6 months and 12 months of treatment, and the clinical data such as the use of other drugs and adverse reactions were observed. Statistical data are collected using the median method, and non-parametric paired Wilcoxon analysis was used for pairwise comparison. Before treatment with omalizumab, the patients' FeNO value was 79(58, 121) ppb, and the total serum IgE was 228(150.5, 345.5) IU/ml. After 6 months of omalizumab therapy, the percent predicted value of the forced expiratory volume in 1 second (FEV1%) before inhaled bronchodilator increased from 86.70(82.65, 91.35)% to 90.90(87.70, 95.85)% (Z=-3.626, P<0.001). The FEV1%pred after inhaled bronchodilator increased from 92.60(85.75, 96.90)% to 94.30(89.95, 98.15)% (Z=-2.178, P=0.029). The absolute value of improvement in FEV1 decreased from 150(95, 210)ml to 50(20, 125) ml (Z=-2.796, P=0.005), and the improvement rate decreased from 6.60(3.80, 7.85)% to 1.90(0.75, 4.85)% (Z=-2.922, P=0.003). After 12 months of treatment, the FEV1%pred before inhaled bronchodilator further increased to 92.90 (91.60, 98.15)% (Z=-3.575, -2.818, and P<0.001, 0.005 compared with before treatment and 6 months after treatment, respectively). The FEV1%pred after inhaled bronchodilator increased to 96.80 (91.90, 101.25)% (Z=-3.622, -1.638, and P<0.001, 0.008 compared with before treatment and after 6 months of treatment, respectively). The absolute value of improvement in FEV1 was 70 (35, 120) ml (P=0.004, 0.842 before treatment and 6 months after treatment, respectively), and the improvement rate was 3.0(1.0, 5.0)% (Z=-2.960, -0.166, and P=0.003, 0.868, compared with before treatment and after 6 months of treatment, respectively). After 12 months of treatment, ACT increased from 13 (10.5, 18) before treatment to 24 (23, 25) (Z=-3.626,P<0.001). Only 1 patient experienced an injection site skin reaction during treatment. Therefore, after 6 months and 12 months of treatment with omalizumab, the patient's lung function improved and symptoms were relieved, which could effectively prevent the acute exacerbation of asthma. Omalizumab treatment is safe and well tolerated, and no effect on blood pressure and blood glucose was observed.
Humans ; Omalizumab/therapeutic use* ; Anti-Asthmatic Agents/therapeutic use* ; Retrospective Studies ; Bronchodilator Agents/therapeutic use* ; Asthma/diagnosis* ; Treatment Outcome

INTRODUCTION: Three doses of SARS-CoV-2 mRNA vaccines have been recommended for cancer patients to reduce the risk of severe disease. Anti-neoplastic treatment, such as chemotherapy, may affect long-term vaccine immunogenicity. METHOD: Patients with solid or haematological cancer were recruited from 2 hospitals between July 2021 and March 2022. Humoral response was evaluated using GenScript cPASS surrogate virus neutralisation assays. Clinical outcomes were obtained from medical records and national mandatory-reporting databases. RESULTS: A total of 273 patients were recruited, with 40 having haematological malignancies and the rest solid tumours. Among the participants, 204 (74.7%) were receiving active cancer therapy, including 98 (35.9%) undergoing systemic chemotherapy and the rest targeted therapy or immunotherapy. All patients were seronegative at baseline. Seroconversion rates after receiving 1, 2 and 3 doses of SARS-CoV-2 mRNA vaccination were 35.2%, 79.4% and 92.4%, respectively. After 3 doses, patients on active treatment for haematological malignancies had lower antibodies (57.3%±46.2) when compared to patients on immunotherapy (94.1%±9.56, P<0.05) and chemotherapy (92.8%±18.1, P<0.05). SARS-CoV-2 infection was reported in 77 (28.2%) patients, of which 18 were severe. No patient receiving a third dose within 90 days of the second dose experienced severe infection. CONCLUSION This study demonstrates the benefit of early administration of the third dose among cancer patients.
Humans ; SARS-CoV-2 ; COVID-19/prevention & control* ; Treatment Outcome ; Neoplasms/drug therapy* ; Hematologic Neoplasms ; Vaccination ; RNA, Messenger ; Antibodies, Viral ; Immunogenicity, Vaccine

BACKGROUND: Data on the immunogenicity and safety of heterologous immunization schedules are inconsistent. This study aimed to evaluate the immunogenicity and safety of homologous and heterologous immunization schedules. METHODS: Multiple databases with relevant studies were searched with an end date of October 31, 2021, and a website including a series of Coronavirus disease 2019 studies was examined for studies before March 31, 2022. Randomized controlled trials (RCTs) that compared different heterologous and homologous regimens among adults that reported immunogenicity and safety outcomes were reviewed. Primary outcomes included neutralizing antibodies against the original strain and serious adverse events (SAEs). A network meta-analysis (NMA) was conducted using a random-effects model. RESULTS: In all, 11 RCTs were included in the systematic review, and nine were ultimately included in the NMA. Among participants who received two doses of CoronaVac, another dose of mRNA or a non-replicating viral vector vaccine resulted in a significantly higher level of neutralizing antibody than a third CoronaVac 600 sino unit (SU); a dose of BNT162b2 induced the highest geometric mean ratio (GMR) of 15.24, 95% confidence interval [CI]: 9.53-24.39. Following one dose of BNT162b2 vaccination, a dose of mRNA-1273 generated a significantly higher level of neutralizing antibody than BNT162b2 alone (GMR = 1.32; 95% CI: 1.06-1.64), NVX-CoV2373 (GMR = 1.60; 95% CI: 1.16-2.21), or ChAdOx1 (GMR = 1.80; 95% CI: 1.25-2.59). Following one dose of ChAdOx1, a dose of mRNA-1273 was also more effective for improving antibody levels than ChAdOx1 (GMR = 11.09; 95% CI: 8.36-14.71) or NVX-CoV2373 (GMR = 2.87; 95% CI: 1.08-3.91). No significant difference in the risk for SAEs was found in any comparisons. CONCLUSIONS: Relative to vaccination with two doses of CoronaVac, a dose of BNT162b2 as a booster substantially enhances immunogenicity reactions and has a relatively acceptable risk for SAEs relative to other vaccines. For primary vaccination, schedules including mRNA vaccines induce a greater immune response. However, the comparatively higher risk for local and systemic adverse events introduced by mRNA vaccines should be noted. REGISTRATION PROSPERO; https://www.crd.york.ac.uk/PROSPERO/ ; No. CRD42021278149.
Adult ; Humans ; BNT162 Vaccine ; 2019-nCoV Vaccine mRNA-1273 ; Network Meta-Analysis ; Immunization Schedule ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Viral Vaccines ; mRNA Vaccines ; Antibodies, Neutralizing ; Antibodies, Viral