Ontogenetic and sexual differences in the venom of Bothrops moojeni: insights from a litter and its mother.

Variability in snake venom composition is well-documented and crucial for understanding snake ecology and predicting snakebites. In this study, we characterize the venom composition and biological activities of newborn female and male Bothrops moojeni and their mother. Our results reveal significant differences between the venom of newborn females and males, demonstrating a broad and diverse range of proteins. The venoms of newborn females showed higher serine protease effects, increased hemorrhagic activity, and greater lethality compared to the venom of newborn males. However, no differences were observed in phospholipase A2 and coagulant activity. The differences in protein composition and toxic activities between maternal and neonatal venom, as well as between the venoms of newborn females and males, contribute to understanding the diverse outcomes of snakebites. These results underscore the importance of considering sex and ontogeny in understanding venom composition in snakes.

Risk of orofacial clefts in relation to maternal body mass index, diabetes and hypertension.

BACKGROUND: To investigate if maternal body mass index, diabetes and hypertension are associated with orofacial clefts. METHODS: Case-control study. Information from 53,188 live births with and without orofacial cleft registered at USA Vital Statistics Natality Birth Data between 2017 and 2021. Case group consisted of all affected live births diagnosed with orofacial clefts (13,297 cases). Comparison group consisted of 39,891 live births without clefts or any other congenital malformation. Information about orofacial cleft cases were compared with the comparison group. The unadjusted and adjusted Odds Ratios were estimated to evaluate the strength of association between mother's pre-pregnancy body mass index, maternal diabetes and hypertension and orofacial cleft occurrence, assuming a p value < 0.05 and 95% confidence intervals (95% C.I.) for statistically significant differences. RESULTS: Mother's pre-pregnancy body mass index, maternal diabetes and maternal hypertension are conditions associated with an increased risk of orofacial cleft development in the child (OR = 1.08, p = 0.004, 95% C.I. = 1.024-1.149; OR = 1.32, 95%, p = 0.000, 95% C.I. = 1.202-1.444; and OR = 1.35, p = 0.000, 95% C.I. = 1.239-1.484; respectively). Maternal ethnicity, sex of infant, and cigarette smoking pregnancy remained as covariates after adjustments in all logistic regression models. CONCLUSION: Due to the increased prevalence of obesity, diabetes, and hypertension, and also to their association with congenital malformations, such as clefts, it is recommended that mothers planning to become pregnant to follow healthy habits, maintain healthy weight, and be screened for possible diabetes or hypertension prior to conception and early in pregnancy.

Care Technologies to Improve Treatment Adherence in Patients Undergoing Organ Transplant: A Scoping Review.

BACKGROUND: The objective of this study was to map care technologies being developed to improve treatment adherence in patients undergoing organ transplant. METHODS: A scoping review was developed according to the Joanna Briggs Institute manual. The research question was developed according to the population, concept, and context strategy. Searches were conducted independently in 6 databases between June and August 2021. The data were evaluated and organized together. The review protocol was published. RESULTS: Fifteen articles were part of the study, mostly published in the United States (33.3%) and in 2016 (33.3%). The main research method identified was clinical studies (80%). Most of the care technologies identified are in relation to medication adherence in the post-transplant setting. Another intervention identified was health education action with the support of mobile apps, electronic monitoring systems, and a card game. CONCLUSIONS: The results present technologies directed at the importance of post-transplant drug adherence; however, it is important to adapt the technologies to the reality experienced by the patient, as well as to train patients so that they can introduce these technologies in their daily lives. Furthermore, it is important that technologies are developed that include other aspects of adherence to post-transplant treatment.

Where do we aspire to publish? A position paper on scientific communication in biochemistry and molecular biology.

The scientific publication landscape is changing quickly, with an enormous increase in options and models. Articles can be published in a complex variety of journals that differ in their presentation format (online-only or in-print), editorial organizations that maintain them (commercial and/or society-based), editorial handling (academic or professional editors), editorial board composition (academic or professional), payment options to cover editorial costs (open access or pay-to-read), indexation, visibility, branding, and other aspects. Additionally, online submissions of non-revised versions of manuscripts prior to seeking publication in a peer-reviewed journal (a practice known as pre-printing) are a growing trend in biological sciences. In this changing landscape, researchers in biochemistry and molecular biology must re-think their priorities in terms of scientific output dissemination. The evaluation processes and institutional funding for scientific publications should also be revised accordingly. This article presents the results of discussions within the Department of Biochemistry, University of São Paulo, on this subject.

Comparison of the effects of 1MHz and 3MHz therapeutic ultrasound on endothelium-dependent vasodilation of humans: a randomised clinical trial.

OBJECTIVE: To compare the effects of different waveforms of 1MHz and 3MHz therapeutic ultrasound on endothelial function in healthy subjects. DESIGN: Randomised placebo-controlled, crossover study with concealed allocation and assessor blinding. SETTING: Imaging Centre of the University Hospital. PARTICIPANTS: Thirty volunteers aged between 18 and 35 years were divided into two homogeneous groups (1MHz and 3MHz). INTERVENTIONS: Continuous (CUT; 0.4W/cm2SATA), pulsed (PUT; 20% duty cycle, 0.08W/cm2SATA) and placebo waveforms (equipment off) of ultrasound (1MHz and 3MHz) were randomized and applied over the brachial artery for 5minutes. MAIN OUTCOME MEASURES: Endothelial function was evaluated using the flow-mediated dilation (FMD) technique. RESULTS: Both 1MHz [CUT: mean difference 4%, 95% confidence interval (CI) 2 to 6%, P<0.001; PUT: mean difference 4%, 95% CI 2 to 6%, P<0.001] and 3MHz (CUT: mean difference 4%, 95% CI 2 to 6%, P<0.001; PUT: mean difference 4%, 95% CI 2 to 6%, P<0.001) of therapeutic ultrasound increased %FMD by approximately 4% compared with the placebo waveforms. The endothelium-dependent vasodilator responses were the same for both types of waves and frequencies. No differences in baseline diameter, hyperaemic flow, and nitroglycerin-mediated diameter and vasodilation were observed between groups. CONCLUSION: Both CUT and PUT ultrasound waveforms improved endothelial function. The 1MHz and 3MHz frequencies of therapeutic ultrasound led to similar improvement in endothelial function in healthy volunteers. Clinical trial registration number RBR-4z5z3t.

Where do we aspire to publish? A position paper on scientific communication in biochemistry and molecular biology

The scientific publication landscape is changing quickly, with an enormous increase in options and models. Articles can be published in a complex variety of journals that differ in their presentation format (online-only or in-print), editorial organizations that maintain them (commercial and/or society-based), editorial handling (academic or professional editors), editorial board composition (academic or professional), payment options to cover editorial costs (open access or pay-to-read), indexation, visibility, branding, and other aspects. Additionally, online submissions of non-revised versions of manuscripts prior to seeking publication in a peer-reviewed journal (a practice known as pre-printing) are a growing trend in biological sciences. In this changing landscape, researchers in biochemistry and molecular biology must re-think their priorities in terms of scientific output dissemination. The evaluation processes and institutional funding for scientific publications should also be revised accordingly. This article presents the results of discussions within the Department of Biochemistry, University of São Paulo, on this subject.

Diaphragm Muscle Surface Electromyography in Patients Submitted to Liver Transplant and Eligible for Extubation.

INTRODUCTION: Liver disease induces many organic and metabolic changes, leading to malnutrition and weight and muscular function loss. Surface electromyography is an easily applicable, noninvasive study, through which the magnitudes of the peaks on the charts depict voluntary muscle activity. AIM: To evaluate the diaphragmatic surface electromyography of postoperative liver transplantation subjects. METHODS: Subjects were patients who underwent liver transplantation and extubation in the Clinical Hospital of State University of Campinas. Electromyography data were collected with support pressure of ≤10 cm H2O, Glasgow Coma Scale = 11, and minimum dosages of vasoactive drugs, and data were collected again 30 minutes after extubation. Signal collection was performed with sEMG System Brazil SAS1000V3 electromyograph and electrode stickers. Statistical analysis was performed using R software. RESULTS: The average time of surgery was 345.36 ± 125.62 minutes. Time from spontaneous mode until extubation was 417.14 ± 362.97 minutes. The RMS (root mean square) values of the right and left domes in spontaneous mode with minimal ventilation parameters were 26.68 ± 10.92 and 26.55 ± 10.53, respectively, and the RMS values after extubation were 31.93 ± 18.69 to 34.62 ± 13.55, for right and left domes. The last calculated pretransplant Model for End-stage Liver Disease score averaged 19.64 ± 8.41. CONCLUSION: There were significant differences between the RMS of the diaphragm domes under mechanical ventilation and after extubation, showing lower effectiveness of the diaphragm muscle against resistance, without the aid of positive pressure and the existing overload of the left dome.

Jararhagin disruption of endothelial cell anchorage is enhanced in collagen enriched matrices.

Hemorrhage is one of the most striking effects of bites by viper snakes resulting in fast bleeding and ischemia in affected tissues. Snake venom metalloproteinases (SVMPs) are responsible for hemorrhagic activity, but the mechanisms involved in SVMP-induced hemorrhage are not entirely understood and the study of such mechanisms greatly depends on in vivo experiments. In vivo, hemorrhagic SVMPs accumulate on basement membrane (BM) of venules and capillary vessels allowing the hydrolysis of collagen IV with consequent weakness and rupture of capillary walls. These effects are not reproducible in vitro with conventional endothelial cell cultures. In this study we used two-dimension (2D) or three-dimension (3D) cultures of HUVECs on matrigel and observed the same characteristics as in ex vivo experiments: only the hemorrhagic toxin was able to localize on surfaces or internalize endothelial cells in 2D cultures or in the surface of tubules formed on 3D cultures. The contribution of matrigel, fibronectin and collagen matrices in jararhagin-induced endothelial cell damage was then analyzed. Collagen and matrigel substrates enhanced the endothelial cell damage induced by jararhagin allowing toxin binding to focal adhesions, disruption of stress fibers, detachment and apoptosis. The higher affinity of jararhagin to collagen than to fibronectin explains the localization of the toxin within BM. Moreover, once located in BM, interactions of jararhagin with α2ß1 integrin would favor its localization on focal adhesions, as observed in our study. The accumulation of toxin in focal adhesions, observed only in cells grown in collagen matrices, would explain the enhancement of cell damage in these matrices and reflects the actual interaction among toxin, endothelial cells and BM components that occurs in vivo and results in the hemorrhagic lesions induced by viper venoms.

Characterization of Neuwiedin, a new disintegrin from Bothrops neuwiedi venom gland with distinct cysteine pattern.

Disintegrins are cysteine-rich toxins containing the RGD motif exposed in a loop that binds integrins such as αIIbß3, α5ß1 and αvß3. The flexibility of the RGD loop, controlled by the profile of the cysteine pairs and the residues flanking the RGD sequence, are key structural features for the functional activity of these molecules. Recently, our group reported a transcript in the venom gland of Bothrops neuwiedi corresponding to a new P-II SVMP precursor, BnMPIIx, in which the RGD-binding loop includes many substituted residues and unique cysteine residues at the C-terminal. In this paper, we obtained the recombinant disintegrin domain of BnMPIIx, Neuwiedin, which inhibited ADP-induced platelet aggregation, endothelial cell adhesion to fibrinogen and tube formation in Matrigel with no particular selectivity to αIIbß3 or endothelial cell integrins. This value was also comparable to the inhibition observed with other recombinant disintegrins with conserved cysteine positions and residues in RGD loop. In this regard, Neuwiedin is an important component to understand the functional relevance of the diversity generated by accelerated evolution of venom toxins as well as to find out eventual new disintegrin-dependent targets that may be approached with disintegrins.

Co-infected HIV/hepatitis patients compared with chronic liver patients and healthy individuals: respiratory assessment through surface electromyography and spirometry.

INTRODUCTION: Co-infected HIV and hepatitis subjects are candidates for a liver transplantation because of progressive liver disease. Chronic liver disease, co-infected or not, requires assessment of respiratory function before liver transplantation. The respiratory evaluation of these 2 groups compared with healthy individuals can define deficits, and this can impair a full recovery after transplant surgery. OBJECTIVE: This study sought to compare the respiratory profile in co-infected patients with chronic liver disease who are candidates for liver transplantation with that of healthy subjects. METHODS: Through respiratory evaluation of flows and lung volumes (spirometry), muscle activity (surface electromyography), and maximum pressure (manovacuometer), 250 people were distributed into 3 groups: 14 patients with HIV and liver disease, 65 healthy subjects, and 171 patients with chronic liver disease. The mean age (years) was respectively 47.5 ± 6.2, 48.3 ± 14.1, and 52.9 ± 8.5. The average body mass index (kg/m(2)) of the groups was 24.6 ± 4.5, 26.0 ± 3.2, and 28.5 ± 5.3, respectively. RESULTS: There was a statistical difference among the groups in the root means square (RMS) rectus abdominis (µV) (P = .0016), RMS diaphragm (µV) (P = .0001), maximal inspiratory pressure (cmH2O) (P = .001), forced exhaled volume at the end of first second (%) (P = .002), and maximal mid expiratory flow 25% to 75% (%) (P = .0001) for the Kruskal-Wallis test. The multivariate analysis among the groups showed that the RMS diaphragm had a tendency to discriminate the co-infected subjects. CONCLUSIONS: The co-infected HIV group showed a muscle deficit of diaphragm and rectus abdominis activity, and the liver disease group showed lower indexes in volumes and respiratory flows.

Correlation between functional capacity and respiratory assessment of end-stage liver disease patients waiting for transplant.

INTRODUCTION: End-stage liver disease has metabolic complications associated with malnutrition, which involves a great loss of muscle mass. This complication can lead to changes in the diaphragm, which along with ascites may impair daily activities and result in global motor disability and physical inactivity of patients on the waiting list for liver transplantation. OBJECTIVES: This study sought to delineate the profile of candidates for liver transplantation while on the waiting list at the Clinical Hospital of State University Campinas (UNICAMP), and to assess and verify whether there is a correlation between functional status of the individuals tested using the 6-minute walk test (6MWT), pulmonary function test (PFT), and respiratory muscle strength with end-stage liver disease candidates for liver transplantation. METHODS: This study was carried out in the Liver Transplantation Unit of the State University of Campinas (UNICAMP). We included 46 patients with end-stage liver disease who underwent the following evaluations: medical history, 6MWT, PFT, maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP), and SF-36. RESULTS: Correlations were found between the respiratory variables 6MWT and PFT. The walked distance was correlated with MIP and MEP. There was no correlation between the 6MWT and the variables body mass index and age. CONCLUSION: Candidates for liver transplantation have decreased muscle strength, normal lung function, and impaired quality of life, mainly due to physical limitations. Functional status may be correlated with the respiratory assessment (muscle strength and pulmonary function test) in liver disease candidates for transplantation.

Surface electromyography for respiratory assessment of liver transplant candidates, healthy subjects and after chevron post-operative incision.

BACKGROUND: Surface electromyography is a noninvasive technique for detecting the activity of skeletal muscles and especially the muscles for respiratory compliance; namely, the diaphragm and rectus abdominis. This study compares these muscles in healthy individuals, liver disease patients, and after abdominal surgery. OBJECTIVE: To study muscle activity by surface electromyography of the right diaphragm muscles and right rectus abdominis (root means square, RMS), and the manovacuometry muscle strength (maximal inspiratory pressure, MIP; and maximal expiratory pressure, MEP). RESULTS: We evaluated 246 subjects who were divided into 3 groups: healthy (65), liver disease (171), and post-surgery (10). In liver disease group the BMI was higher significantly for ascites (P = .001), and was increase in RMS rectum (P = .0001), RMS diaphragm (P = .030), and a decreased inspiratory and expiratory indices (P = .0001) pressure in the post-surgery group. A multivariate analysis showed tendency to an increased BMI in liver disease and in the post-surgery groups correlated with an increased RMS rectum and the lower MIP/MEP (P = .11). The receiver operating characteristic curve showed that RMS rectus was capable of discriminating liver disease and post-surgery patients from healthy subjects (area = 0.63; 95% CI 0.549-0.725). CONCLUSION: The muscle activity of normal individuals is lower than in subjects with deficit muscles because less effort is necessary to overcome the same resistance, observed by surface electromyography and muscle strength.

Effects of a respiratory physiotherapeutic program in liver transplantation candidates.

BACKGROUND: Candidates for liver transplantation may have malnutrition, fatigue, loss of muscle mass and function. The combination of these factors leads to overall physical disability and physical inactivity. OBJECTIVE: The aim of the study was to evaluate the effects of a respiratory physiotherapeutic program on liver transplantation candidates. METHOD: Forty-two patients were evaluated by respiratory muscle strength, surface electromyography of the rectus abdominis and diaphragm, and spirometry. We also applied the SF-36. The patients were divided into two groups: 12 randomly assigned to the control group and 5 in the intervention group. The intervention consisted of an explanatory and illustrative manual to be followed at home with diaphragmatic breathing exercises, diaphragmatic isometric exercise, Threshold IMT, lifting the upper limbs with a bat, and strengthening the abdominals. RESULTS: Significant difference was found between initial forced expiratory flow (FEF)25-75% (P = .042) and final FEF25-75 in the intervention group. The control group had significant difference (P = .036) in the diaphragm RMS between initial time and end time. In conclusion, the control group showed greater electrical activity of the diaphragm after 3 months. CONCLUSION: The intervention group benefited from the exercise, thus improving the FEF25-75%.

Evaluation of functional status, pulmonary capacity, body composition, and quality of life of end-stage liver disease patients who are candidates for liver surgery.

INTRODUCTION: Muscular weakness in combination with malnutrition can induce a global motor impairment and physical inactivity, adversely impairing the daily living activities and quality of life of end-stage liver disease patients who are candidates for liver transplantation. OBJECTIVES: To evaluate functional status, pulmonary capacity, body composition and quality of life in end-stage liver disease patients who are candidates for liver transplantation; to verify if there is a correlation between the functional variables of the individuals tested through the 6-minute walk test (6MWT) and covariables: pulmonary function test (PFP), quality of life and body composition. METHODS: This study was carried out at the Liver Transplantation Unit of the State University of Campinas (UNICAMP). We included 46 patients with end-stage liver disease who underwent the following evaluations: medical history, quality of life questionnaire "Short Form 36" (SF-36), surface electromyography (sEMG) of the diaphragm and rectus abdominis muscles, body composition assessment by electrical vioimpedance (BIA), 6MWT and PFP. RESULTS: Univariate analysis and Pearson's correlation found correlations between distance walked on 6MWT and QOL (P = .006 and P = .02) and TBW (P = .5 and P = .02). Pearson's correlation were found between respiratory variables of 6MWT, QOL, and PFP. CONCLUSION: The functional status may be correlated to body composition, quality of life and pulmonary capacity of patients with liver disease, candidates for transplantation.

Profile of respiratory evaluation through surface electromyography, manovacuometry, and espirometry in candidates on the liver transplant waiting list.

INTRODUCTION: Electromyography (EMG) is the examination of skeletal muscle membrane electrical activity in response to physiologic activation. In healthy muscles, the square root (root mean square [RMS] is related to the amplitude of the obtained signal. Respiratory muscles are studied, especially those important for compliance, the diaphragm and the rectus abdominis. An evaluation to detect respiratory muscle deficits among liver disease patients on the waiting list for transplantation may serve as an alternative to providing specific treatments reducing the possibility of respiratory complications after transplantation. OBJECTIVE: To study muscle activity by evaluating respiratory and surface EMG of the right diaphragm and right rectus abdominis muscles in patients on the liver transplant waiting list. METHOD: Respiratory evaluation of muscle strength (maximum inspiratory pressure [MIP] and maximum expiratory pressure [MEP]) with a manometer -300, +300 from Gen-air; spirometry with Easyware Spirometer version 2.20; pulse oximetry with Nonim oximeter; Model for End-Stage Liver Disease (MELD) score as well as surface EMG of the diaphragm and rectus abdominis muscles from EMG/Brazil were applied in healthy and liver diseased subjects. RESULTS: The 87 liver disease patients showed a mean age of 53.9 ± 7.3 years, mean body mass index of 28.21 ± 5.04 kg/m2 with 24.14% smokers (n = 21) and 43.68% physically active (n = 38 p) showing Diaphragm RMS of 61.05 ± 68.48 µV; rectus abdominis RMS of 45.28 ± 53.82 µV; MEP of 100.28 ± 27.85 cm H(2)O; and MIP of 92.41 ± 29.77 cm H2O. The average MELD of studied patients was 16.5 ± 0.71. CONCLUSION: The respiratory profiles of patients on the liver transplant waiting list concerning muscle support were precarious owing to ascites and motor adynamia.

Identification of a DNA methylation point in the promoter region of the bovine CYP21 gene.

The CYP21 (steroid 21-hydroxylase) gene is involved in the synthesis of steroid hormones. Bov-A2 is a retroposon that is common in ruminant genomes. The promoter region of bovine CYP21 contains a short interspersed nucleotide element of Bov-A2, which overlaps a putative Sp1 binding site. We looked for RFLP/HpaII polymorphism in the Bov-A2 element in bovine Zebu breeds by PCR-RFLP, and examined whether polymorphism in this element is associated with methylation. Among DNA samples from 135 Brazilian Zebu breed cattle, we identified an RFLP/HpaII polymorphism (T/C), which, based on a restriction methylation-sensitive assay employing HpaII and isoschizomer MspI enzymes (methylation-sensitive and -non-sensitive enzymes, respectively), appears to be a DNA methylation point. This is the first report of this polymorphism and on DNA methylation in the bovine CYP21 promoter region in Brazilian Zebu cattle.

Validation of 20-meter corridor for the 6-minute walk test in men on liver transplantation waiting list.

BACKGROUND: Guidelines established by the American Thoracic Society recommend the use of corridors 30 m in length for the 6-minute walk test (6MWT). However, not all institutions have such long corridors, which hinders or prevents 6MWT performance and use of its benefits. OBJECTIVE: To compare the distances walked by male patients with cirrhosis on the liver transplantation waiting list, we performed 6MWT on corridors 20 and 30 m long. METHODS: This prospective study included 10 patients on the waiting list for liver transplantation. They underwent 2 walk tests: the first test in a 20 m corridor and the second in a 30 m corridor. We assessed physiologic variables (heart rate, oxygen saturation, arterial blood pressure) and the subjective sensation of dyspnea at rest at 6 and 9 minutes after each walk. Statistical analysis was performed using the Wilcoxon test. RESULTS: Data are expressed as mean ± sd. Patient age was 59 ± 10 years. The distances walked by the patients were shorter than those predicted for their age and gender (586 ± 45 m) in both tests, no significant difference was observed between the first and the second 6MWT (437 ± 101 m vs 465 ± 80 m; P=.131) or among the physiologic variables. CONCLUSION: We concluded that a 20 m corridor can be used safely and effectively as an alternative to 30 m for the 6MWT for male patients with cirrhosis on the liver transplantation waiting list.

Comparison of surface electromyography in respiratory muscles of healthy and liver disease patients: preliminary studies.

INTRODUCTION: Surface electromyography (SEMG) is described as a technique to detect voluntary muscle activity. In the respiratory muscles, diaphragm and the rectus abdominis-are especially important for respiratory compliance. OBJECTIVE: We sought to study the activity of muscles using SEMG of the right diaphragm and the right rectus abdominis in healthy subjects versus liver disease patients (LDS). METHOD: Each group of 30 male patients underwent SEMG with electrodes attached to the dermis surface at the xiphoid and below the right costal margin (channel 1). For the rectus abdominis, we placed the electrodes on the right 5 cm below the umbilicus. The variables studied were: root mean square (RMS), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP). We also evaluated age, weight, body mass index, smoking history lifestyle sedentary preexistent chronic lung disease. Nonparametric tests were used for statistical analysis. RESULTS: There were significant differences (P>0001) between the groups regarding MEP and MIP values showing low pressures in the LDS group. RMS of the rectus abdominis showed a trend (P=.059) toward compliance in the LDS group. Compared with the healthy subjects, there were 18% versus 5% sedentary individuals; only 10% versus 27.3% were smokers or former smokers and chronic lung disease was present in 2% versus 4%. CONCLUSION: The respiratory muscle evaluation using SEMG detected decreased respiratory muscle strength and a trend to rectus abdominis compliance among LDS.

Immunochemical and biological characterization of monoclonal antibodies against BaP1, a metalloproteinase from Bothrops asper snake venom.

BaP1 is a P-I class of Snake Venom Metalloproteinase (SVMP) relevant in the local tissue damage associated with envenomations by Bothrops asper, a medically-important species in Central America and parts of South America. Six monoclonal antibodies (MoAb) against BaP1 (MABaP1) were produced and characterized regarding their isotype, dissociation constant (K(d)), specificity and ability to neutralize BaP1-induced hemorrhagic and proteolytic activity. Two MABaP1 are IgM, three are IgG1 and one is IgG2b. The K(d)s of IgG MoAbs were in the nM range. All IgG MoAbs recognized conformational epitopes of BaP1 and B. asper venom components but failed to recognize venoms from 27 species of Viperidae, Colubridae and Elapidae families. Clone 7 cross-reacted with three P-I SVMPs tested (moojeni protease, insularinase and neuwiedase). BaP1-induced hemorrhage was totally neutralized by clones 3, 6 and 8 but not by clone 7. Inhibition of BaP1 enzymatic activity on a synthetic substrate by MABaP1 was totally achieved by clones 3 and 6, and partially by clone 8, but not by clone 7. In conclusion, these neutralizing MoAbs against BaP1 may become important tools to understand structure-function relationships of BaP1 and the role of P-I class SVMP in snakebite envenomation.

Immunochemical and biological characterization of monoclonalantibodies against BaP1, a metalloproteinase from Bothrops aspersnake venom

BaP1 is a P-I class of Snake Venom Metalloproteinase (SVMP) relevant in the local tissue damage associated with envenomations by Bothrops asper, a medically-important species in Central America and parts of South America. Six monoclonal antibodies (MoAb) against BaP1 (MABaP1) were produced and characterized regarding their isotype, dissociation constant (Kd), specificity and ability to neutralize BaP1-induced hemorrhagic and proteolytic activity. Two MABaP1 are IgM, three are IgG1 and one is IgG2b. The Kds of IgG MoAbs were in the nM range. All IgG MoAbs recognized conformational epitopes of BaP1 and B. asper venom components but failed to recognize venoms from 27 species of Viperidae, Colubridae and Elapidae families. Clone 7 cross-reacted with three P-I SVMPs tested (moojeni protease, insularinase and neuwiedase). BaP1-induced hemorrhage was totally neutralized by clones 3, 6 and 8 but not by clone 7. Inhibition of BaP1 enzymatic activity on a synthetic substrate by MABaP1 was totally achieved by clones 3 and 6, and partially by clone 8, but not by clone 7. In conclusion, these neutralizing MoAbs against BaP1 may become important tools to understand structure–function relationships of BaP1 and the role of P-I class SVMP in snakebite envenomation.