Correlation of Blomia tropicalis-specific immunoglobulin epsilon profiles with family history of atopy in a Filipino population.

Background: House dust mites are the major source of indoor allergens in the tropical and subtropical regions with Blomia tropicalis (Bt) allergens as one of the leading causative agents of sensitization among patients from the tropics. Despite the clinical importance of Bt in various populations, its allergenicity remains unclear among Filipino allergic patients. Objective: This study determined the sensitization profiles of allergic Filipinos against Bt allergens and its correlation with atopy. Methods: Total immunoglobulin epsilon (IgE) (n = 960), Bt-specific IgE (n = 247), and Blomia tropicalis 5 (Blo t 5)-specific IgE (n = 87) profiles of allergic and nonallergic subjects were measured through enzyme-linked immunosorbent assay (ELISA). Point-biserial correlation coefficient was used to determine the association between Bt-specific IgE levels and selected demographics. Inhibition ELISA was performed to measure the inhibition capacity of recombinant Blo t 5 (rBlo t 5) against Bt allergen extracts. Results: Mean total IgE levels of allergic cases (n = 171) were significantly higher (P < 0.001) compared to the mean IgE levels of nonallergic controls (n = 76). Among allergic subjects, 58% were sensitized to Blo t extract and 80% of which were sensitized to rBlo t 5 allergen. A positive correlation was observed between Bt-specific IgE and family history of atopic disease (P = 0.031). Inhibition assay revealed that 54% mean reactivity of 7 plasma samples was caused by rBlo t 5, validating that rBlo t 5 is a major allergen in Bt. Conclusions: This study has shown the importance of Bt as an allergen source that sensitizes atopic Filipino subjects. Hence, inclusion of Bt allergen extract and rBlo t 5 in the panel for allergy diagnosis and immunotherapy in Filipino populations is strongly recommended.

Correction: de Jesus et al. Voacanga globosa Spirobisindole Alkaloids Exert Antiviral Activity in HIV Latently Infected Cell Lines by Targeting the NF-κB Cascade: In Vitro and In Silico Investigations. Molecules 2022, 27, 1078.

There was an error in the original publication [...].

Association of interleukin-13 gene single nucleotide polymorphism rs1800925 with allergic asthma in Asian population: A meta-analysis.

Background: The interleukin-13 (IL-13) gene has been associated with allergic asthma pathogenesis due to its role in IgE synthesis. The IL-13 single nucleotide polymorphism (SNP) rs1800925 has been implicated in exacerbated allergic asthma symptoms in different ethnicities. Objectives: To determine the association of IL-13 SNP rs1800925 with allergic asthma symptoms in the Asian population. Methods: Major databases were searched for studies on the association of IL-13 rs1800925 with allergic asthma in various Asian populations published between 2010 and February 2022. The odds ratio with 95% CI was obtained from included studies, and the association was evaluated using different genetic models. Heterogeneity was explored by subgroup analyses and I2 statistic evaluation. Results: Eleven studies with a total of 2895 cases and 2914 controls were included in this meta-analysis. The majority of the cases exhibited CC genotype (n = 1897), followed by CT genotype (n = 852), and TT genotype (n = 146). IL-13 rs1800925 was significantly associated with increased allergic asthma risk in the Asian population under the recessive model (TT vs CT/CC: OR, 1.48; 95% CI, 1.14-1.93; P = 0.37; I2 = 08%). Subgroup analyses by ethnicity showed an elevated risk of allergic asthma in West Asians (Iranian and Saudi Arabian) followed by East Asians (Chinese and Japanese) using the recessive model. Both age groups (adults and children) exhibited an increased risk of allergic asthma. Conclusion: This meta-analysis provides evidence that IL-13 SNP rs1800925 is a risk factor for allergic asthma in the Asian Population. It also suggests that rs1800925 is a risk factor present in both adult and children population.

Voacanga globosa Spirobisindole Alkaloids Exert Antiviral Activity in HIV Latently Infected Cell Lines by Targeting the NF-kB Cascade: In Vitro and In Silico Investigations.

Since the efficiency in the transcription of the HIV genome contributes to the success of viral replication and infectivity, we investigated the downregulating effects of the spirobisindole alkaloids globospiramine (1), deoxyvobtusine (2), and vobtusine lactone (3) from the endemic Philippine medicinal plant, Voacanga globosa, during HIV gene transcription. Alkaloids 1-3 were explored for their inhibitory activity on TNF-α-induced viral replication in two latently HIV-infected cell lines, OM10.1 and J-Lat. The induction of HIV replication from OM10.1 and J-Lat cells elicited by TNF-α was blocked by globospiramine (1) within noncytotoxic concentrations. Furthermore, globospiramine (1) was found to target the NF-ĸB activation cascade in a dose-dependent manner when the transcriptional step at which inhibitory activity is exerted was examined in TNF-α-induced 293 human cells using transient reporter (luciferase) gene expression systems (HIV LTR-luc, ĸB-luc, and mutant ĸB-luc). Interrogation through molecular docking against the NF-ĸB p50/p65 heterodimer and target sites of the subunits comprising the IKK complex revealed high binding affinities of globospiramine (1) against the S281 pocket of the p65 subunit (BE = -9.2 kcal/mol) and the IKKα activation loop (BE = -9.1 kcal/mol). These findings suggest globospiramine (1) as a molecular inspiration to discover new alkaloid-based anti-HIV derivatives.

K-12 education in biochemistry and molecular biology: A parallel session at the IUBMB/PSBMB 2019 "Harnessing Interdisciplinary Education in Biochemistry and Molecular Biology" conference.

Biochemistry and molecular biology education starts before our students get to university. From a very early age, they start learning informally about science beginning with the basics of science and as they progress through their school years they should be exposed to more advanced topics such as biochemistry and molecular biology. This session at the conference focused on three very different examples of engaging school students with biochemistry and molecular biology.

Development of a Gold Nanoparticle-labeled Sandwich Format Lateral Flow Immunoassay Kit for the Detection of Tropical House Dust Mite Suidasia pontifica.

BACKGROUND: The house dust mite Suidasia pontifica (Sp) is an important source of allergens in tropical regions that trigger IgE-mediated allergic reactions such as allergic asthma, atopic dermatitis and allergic rhinitis. Detection of Sp-specific proteins are important in the management and prevention of allergic diseases. OBJECTIVE: The study aimed to provide a proof of concept for a gold nanoparticle-labeled sandwich format Lateral Flow Immunoassay (LFIA) kit for the detection of Sp-specific proteins. METHODS: Protein A chromatography-purified rabbit anti-Sp polyclonal antibodies were labeled with gold nanoparticles (AuNP) synthesized from chloroauric acid using the citrate reduction method, then dispensed on a glass fiber pad. Unlabeled antibodies and anti-rabbit IgG were immobilized onto nitrocellulose membrane as test line and control line respectively. Cellulose fiber pad, glass fiber, and the nitrocellulose membrane pad were then assembled as LFIA kit. RESULTS: Protein-A affinity chromatography purification with pre-concentration yielded 1.45 mg/mL of anti-Sp polyclonal antibodies. Synthesized AuNPs with ~20 nm sizes observed under transmission electron microscope were used for antibody conjugation at an optimal pH of 8.5 (borate buffer) and an optimal ratio of 10 µ L 50µg/mL antibody:100 µ L AuNP. Optimal color intensity and fastest migration time were observed with the treatment of 0.05% Tween20 and 10% sucrose in the conjugate pads; 5% BSA and 0.05% Tween20 in the sample pads, and 1% BSA in the test pads. The limit of detection of the LFIA Sp-specific proteins is 0.076 µg/mL. The sensitivity of the Sp LFIA kit is 83% while the specificity is 100%. CONCLUSION: This is the first report of a prototype for a cost-effective, rapid, and equipment-free detection of the house dust mite Suidasia pontifica.

Efficacy and safety of Tinospora cordifolia lotion in Sarcoptes scabiei var hominis-infected pediatric patients: A single blind, randomized controlled trial.

OBJECTIVE: To evaluate the clinical efficacy and safety of Tinospora cordifolia lotion including its cure rate and clearance time compared with permethrin lotion. MATERIALS AND METHODS: A single blind, randomized, controlled, pilot clinical study was performed in three government institutions to investigate clinical efficacy of T. cordifolia lotion in sixty-six clinically-diagnosed scabies-infected patients. The patients were treated with T. cordifolia or permethrin lotions for three consecutive days for two weeks and clinical assessment of each patient was performed for five weeks. RESULTS: T. cordifolia lotion and permethrin significantly reduced the mean global evaluation score after four weeks of treatment. The two lotions showed comparable effects as anti-scabies agent. Moreover, the clearance time (days) and cure rate using the two lotions did not differ. Clinical improvement, mean clearance time and cure rate of T. cordifolia lotion are comparable with permethrin. CONCLUSIONS: Tinospora cordifolia lotion exhibits anti-scabies activity comparable with permethrin. Its incorporation as therapeutic reagent in Sarcoptes scabiei infections is highly recommended.

Biomarker detection in urinary proteome of prostate cancer by nanoflow LC-MS/MS

INTRODUCTION: Urinary proteomics provides a wealth of information in the identification of protein markers associated with various diseases such as in carcinoma. With the increasing incidence of prostate cancer and the lack of sensitivity and specificity of prostate specific antigen, the simultaneous identification of an alternative protein biomarker through urinary proteomics is encouraging. Urine, which has similar proteins with serum, makes it an ideal alternative biofluid wherein the collection is easy and non-invasive.METHODS: Urinary proteins were separated by gradient SDS-PAGE followed by in-gel digestion and organic/buffer peptide extraction. The protein biomarkers in prostate cancer patients and control subjects were identified via LC-MS/MS and submitted to Protein Prospector where the peptide fragmentation of sequence was analyzed and compared with the SwissProt database.RESULTS: A panel of three protein biomarkers for the early detection of prostate cancer were identified: transthyretin, hemoglobin subunit alpha and hemoglobin sububit beta. The presence of these three biomarkers is associated with high Gleason scores and TNM stages but not with PSA level. Uromodulin and mannan binding lectin serine protease cancer from BPH. The study also revealed the divergence of the urinary proteome of the cancer patients from the urinary proteome of the control with BPH suggesting the fundamental differences in benign and malignant growth of the prostate epithelial cells. Another highlight of the study was the identification of oxidation of pro63 of transthyretin in patient 3. The proposed role of the post translational modification in pro63 of transthyretinin in the mechanism of prostate carcinogenesis remains to be defined and warrants further study.CONCLUSION: Our study was able to establish the homology of urine proteome among the controls and its divergence from the patients afflicted with prostate cancer by simultaneously comparing their urine proteomes leading to the identification of a distinct panel of biomarkers, namely, transthyretin, hemoglobin subunit alpha and hemoglobin subunit beta. Uromodulin and mannan binding lectin serine protease 2 are the additional biomarkers that can distinguish prostate cancer from BPH. Due to limitations in the number of controls and patients, only preliminary findings and their significance were shown. These findings need to be confirmed in future investigations using larger sample size for both the controls and the patients.

Immunoglobulin E-binding reactivities of natural pollen grain extracts from selected grass species in the Philippines.

BACKGROUND: Pollen grains have been reported to be present in the Philippine atmosphere but studies regarding their allergenicity are limited. OBJECTIVE: The present study aimed to profile the sensitization of allergic individuals to selected grass pollen species and to characterize the pollen proteins that may be responsible for this allergenic response. METHODS: The protein profile of the grass pollen extracts from Cynodon dactylon, Saccharum spontaneum, Sporobulus indicus, Chloris barbata, Oryza sativa, Imperata cylindrica, and Zea mays was analyzed by Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis. The specific-IgE profile of the allergic individuals and the allergenic potential of the pollen extracts were evaluated through Enzyme-linked Immunosorbent Assay and IgE immunoblotting. RESULTS: Sensitization of the allergic individuals to the pollen extracts was detected with I. cylindrica and O. sativa to be the most frequently recognized with more that 92% reactivity, whereas for C. dactylon and Z. mays, were found to have less than 25% reactivity. CONCLUSION: Multiple IgE-binding proteins from S. indicus, S. spontaneum and C. barbata that were detected may be responsible for the allergic reactions among Filipino subjects.

IgE cross-reactivity between house dust mite allergens and Ascaris lumbricoides antigens.

BACKGROUND: Common antigens between intestinal parasites and environmental allergens may play a role in the modulation of allergic immune responses. There is a growing interest in investigating cross-reactivity between common helminths and dust mites affecting humans, particularly in the tropics. OBJECTIVE: This study examined the cross-reactivity between the human roundworm Ascaris lumbricoides (Al) and three house dust mite (HDM) species. METHODS: Specific serum IgE levels to HDM species Blomia tropicalis (Bt), Dermatophagoides pteronyssinus (Dp), and Dermatophagoides farinae (Df ); and Al extracts among allergic (n=100) and ascariasis (n=60) subjects were measured through enzyme-linked immunosorbent assay (ELISA). IgE-reactive components of HDM and Al extracts were detected through Western-Blot Analysis. Cross-reactivity between HDMs and Al was determined by ELISA inhibition using HDM and Al-specific sera from allergic (n=15) and ascariasis (n=15) subjects. The IgE-binding capacity of a recombinant paramyosin peptide (Blo t 11-fD) to allergic (n=50) and ascariasis (n=50) subjects' sera were likewise determined. RESULTS: Among allergic subjects, 70% exhibited Al-specific positive IgE-reactivity, while 20-28% of ascariasis subjects demonstrated HDM-specific positive IgE-reactivity. Multiple IgE-reactive components of HDM allergens (14-240 kDa) and Al antigens (15-250 kDa) were detected, indicating multi-allergen sensitization among the subjects tested. Al antigens can inhibit up to 92% of HDM-specific IgE-reactivity among allergic subjects, while up to 54% of Al-specific IgE-reactivity among ascariasis subjects was inhibited by HDM allergens. Positive rBlo t 11-fD-specific IgE reactivity was observed in 80% of the allergic subjects and 46% of the ascariasis subjects. CONCLUSIONS: This study showed the presence of multiple cross-reactive antigens in HDM and Al extracts. Identification of these molecules may provide basis for designing novel diagnostic and therapeutic strategies. The potential role of paramyosin as a specific cross-reactive allergen present in HDMs and Al has been shown.

Association of house dust mite-specific IgE with asthma control, medications and household pets.

BACKGROUND: Evidence is conflicting regarding the effectiveness of creating a low-allergen environment or reducing allergen exposure to control asthma exacerbations. OBJECTIVE: This study determined the association of house dust mite (HDM)-specific IgE levels with asthma symptom control, selected medications, family history of allergic disease, and exposure to second-hand smoke and household pets. METHODS: Serum samples from 102 doctor-diagnosed allergic asthma patients and 100 non-atopic controls were subjected to enzyme-linked immunosorbent assay using the HDM species Dermatophagoides pteronyssinus (Dp), Dermatophagoides farinae (Df), and Blomia tropicalis (Bt) allergens. Point-biserial correlation coefficient, Pearson R correlation, and logistic regression analyses were used to determine association of HDM-specific IgE levels with the abovementioned variables. RESULTS: Of the 102 cases, 38.24%, 47.06%, and 33.33% were sensitized to Bt, Df, and Dp, respectively. Sensitized patients showed greater probability [Bt (OR = 1.21), Df (OR = 1.14), and Dp (OR = 1.35)] to manifest symptoms than those who were not. Obtained p-values [Bt (p = 0.73), Df (p = 0.83), and Dp (p = 0.59)], however, proved that HDM-specific IgE levels had no significant contribution in predicting or explaining occurrence of asthma symptoms. Bt- and Df-specific IgEs showed moderately weak but significant relationship with bambuterol HCl and expectorant, respectively. Patients currently on said medications registered higher HDM-specific IgE levels than those who were not. No significant correlation between IgE levels and family history of allergic disease or with exposure to second-hand smoke was seen. Dp-specific IgE levels of patients exposed to household pets were significantly lower compared to those without exposure. CONCLUSION: This study proves that sensitization to Bt, Df, and Dp allergens is not significantly associated with asthma symptoms and control. Although cases were shown to be sensitized to HDMs, their current medications were at least effective in controlling their asthma symptoms.

Correlation of the 5'untranslated region (5'UTR) and non-structural 5B (NS5B) nucleotide sequences in hepatitis C virus subtyping.

The 5'untranslated region (5'UTR) is often targeted to detect major genotypes in hepatitis C virus (HCV) but its insufficient sequence variation limits its usefulness for differentiating HCV subtypes. Subtyping has important implications to epidemiologic studies, clinical management, and vaccine development. Analysis of the nucleotide sequence of variable regions such as the non-structural 5B (NS5B) is considered the reference method for identifying HCV subtypes. We evaluated the accuracy of subtyping of HCV genotype 1 (HCV-1) samples from the Philippines by 5'UTR sequencing as compared with the NS5B sequence. A total of 30 patients infected with HCV-1 previously confirmed by PCR-RFLP and clinically diagnosed with chronic hepatitis C were analyzed. Nucleotide sequencing of the 5'UTR showed that 15 (50%) were identified as 1a and 15 (50%) were identified as 1b. Sequence analysis of the NS5B revealed that 13 (43%) belonged to subtype 1a while 17 (57%) belonged to subtype 1b. The most predominant subtype was 1b by NS5B sequencing. The predictive value of 5'UTR sequencing to subtype 1a was 73% while for subtype 1b, predictive value was 87%. Overall concordance between 5'UTR and NS5B sequencing was 80%. NS5B sequence and phylogenetic analysis is still the reference method for identifying HCV-1a and 1b subtypes.

The -590C/TIL4 single-nucleotide polymorphism as a genetic factor of atopic allergy.

Elevated IgE levels in individuals with asthma, allergic rhinitis, and atopic dermatitis represents a situation in that increased IL4 production seems to occur because of the genetic component of the disease. In this study, one-hundred two matched-pairs of allergic and non-allergic individuals were phenotyped for total serum IgE level using enzyme-linked immunosorbent assay (ELISA). Atopic status was defined by serum IgE concentration ≥100 IU/mL The -590C/T IL4 (rs2243250) was screened by polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis. An association between the IL4 -590 TT genotype and levels of IgE was confirmed in the study population (ANOVA p=0.017). Furthermore, the IL4 T allele was significantly increased in allergic (0.299) compared with non-allergic subjects (0.172) (OR=2.060, 95% 01 = 1.285-3.301, χ(2) uncorrected p=0.002) at total serum IgE cut-off of 100 IU/mL. A significant relationship between IL4 -590 TT genotype and very high IgE levels (>1000 IU/mL) (OR=3.968, 95% CI = 1.499-10.5, χ(2) uncorrected p=0.01624) was also established. The -590C/T IL4 polymorphism is a potential risk factor to and correlates with atopic allergy.

Concordance of hepatitis C virus subtyping by non-structural 5A and non-structural 5B sequencing

The non-structural 5B (NS5B) gene is the target region to identify hepatitis C virus (HCV) subtypes. However, it is not always possible to amplify this region because of inherently high sequence variability. Nucleotide sequences of the non-structural 5A (NS5A) and NS5B genes and its concordance were determined from patients infected with HCV genotype 1 (HCV-1). Among the 30 HCV-1 samples, 7 (23%) were identified as subtype 1a and 23 (77%) were identified as 1b by NS5A sequencing. Sequence analysis of the NS5B showed that 13 (43%) were identified as 1a and 17 (57%) were identified as 1b. Out of the 13 samples identified as 1a by NS5B, 6 (46%) were correctly identified by NS5A. Of the 17 samples identified as 1b by NS5B, 16 (94%) were correctly identified by NS5A. The presence of glutamic acid (E) or aspartic acid (D) at position 2225 in the NS5A differentiates 1a from 1b subtypes, respectively. This study showed that the NS5A sequencing can identify HCV-1a and 1b subtypes with predictive values of 86% and 70% of cases, respectively. The overall concordance with NS5B was 73%. NS5B sequence analysis remains to be the reference method to identify HCV-1 subtypes. NS5A sequencing may be used to complement NS5B sequencing in case the NS5B gene cannot be successfully amplified.

Mite amylase from Blomia tropicalis (Blo t 4): differential allergenicity linked to geographical regions.

BACKGROUND: Blomia tropicalis is an important domestic dust mite in the tropics and subtropics. This study describes cDNA cloning of the group 4 allergen of B. tropicalis, and the evaluation of the sensitization of this allergen in atopic populations from 2 geographic regions. METHODS: cDNA cloning was carried out using the Smart RACE cDNA amplification kit. The full-length Blo t 4 cDNA was isolated by cDNA library screening, 5' and 3' rapid amplification of cDNA ends and long-distance PCR. Sequence analysis was performed with a combination of the Clustal W, CGC and Blast program packages. The cDNA was expressed in Pichia pastoris yeast. The skin prick test was used to evaluate the sensitization profile of recombinant Blo t 4, crude dust mite allergen extracts and major B. tropicalis recombinant allergen Blo t 5. RESULTS: The cloned Blo t 4 had a molecular weight of 56 kDa and had 68% amino acid homology with group 4 allergens of Dermatophagoides pteronyssinus and 65% with those of Euroglyphus maynei. A sensitization profile to the expressed recombinant Blo t 4 allergen (28%) showed an unusually higher frequency than to the major allergen Blo t 5 (22%) in allergic subjects from Chengdu, PR China. In comparison, the subjects from Singapore showed very low sensitization to Blo t 4 (4%) compared with Blo t 5 (84%). CONCLUSIONS: Group 4 allergens of B. tropicalis may be an important dust mite allergen in certain distinct populations.

Recombinant proteins and peptides as diagnostic and therapeutic reagents for arthropod allergies.

Domestic arthropods are chief sources of potent allergens that trigger sensitization and stimulate IgE-mediated allergies. Diagnosis and immunotherapy of arthropod allergies rely on the use of natural allergen extracts which are associated with low specificity and efficacy, the risk of anaphylactic reactions, and the extended period of treatment. Most of the problems associated with natural allergen extracts for allergy diagnosis and immunotherapy can be circumvented with the use of recombinant allergens and peptides. Recombinant allergens are recently developed for microarray-based multi-allergen tests which provide component-resolved diagnosis (CRD) of the patient's sensitization profile. Moreover, recombinant protein technology and peptide chemistry have been used to construct isoallergens, allergen mutants, allergoids, T and B cell peptides, hypoallergens, and mimotopes with reduced allergenicity but enhanced immunogenicity for allergen-specific immunotherapy (SIT) and vaccination. The basics of recombinant arthropod allergen technology are in place providing a lucid future for the advancement of diagnosis and immunotherapy of arthropod allergies.