Neutralizing antibody responses to the Delta variant of SARS-CoV-2 following vaccination with Ad5-nCoV (CanSino) in the Mexican population.

During the COVID-19 pandemic, the Ad5-nCoV vaccine was applied to the Mexican population before the WHO approved it. In a transversal study, we compare the CanSino vaccine efficacy and a natural SARS-CoV-2 infection in eliciting neutralizing antibodies against the SARS-CoV-2 Delta variant in Guadalajara, Mexico. Participants between 30-60 years were included in the study and classified into three groups: 1) Natural immunity (unvaccinated), 2) Vaccine-induced immunity (vaccinated individuals without a COVID-19 history), and 3) Natural immunity + vaccine-induced immunity. These groups were matched by age and gender. We assessed the ability of individuals' serum to neutralize the Delta variant and compared the results of the different groups using a neutralization test followed by plaque-forming units. Results showed that 39% of individuals' serum with a history of COVID-19 (natural immunity, Group 1) could not neutralize the Delta variant, compared to 33% in vaccinated individuals without COVID-19 (vaccine immunity, Group 2). In contrast, only 7% of vaccinated individuals with a history of COVID-19 (natural + vaccine immunities) could not neutralize the Delta variant. We concluded that the effectiveness of the Ad5-nCoV vaccine to induce neutralizing antibodies against the Delta variant is comparable to that of natural infection (61% vs. 67%). However, in individuals with both forms of immunity (Group 3), it increased to 93%. Based on these results, despite the Ad5-nCoV vaccine originally being designed as a single-dose regimen, it could be recommended that even those who have recovered from COVID-19 should consider vaccination to boost their immunity against this variant.

The Value of CXCL1, CXCL2, CXCL3, and CXCL8 as Potential Prognosis Markers in Cervical Cancer: Evidence of E6/E7 from HPV16 and 18 in Chemokines Regulation.

Cervical cancer (CC) is a serious global health issue, and it is well-known that HPV infection is the main etiological factor that triggers carcinogenesis. In cancer, chemokine ligands and receptors are involved in tumor cell growth, metastasis, leukocyte infiltration, and angiogenesis; however, information on the role played by E6/E7 of HPV16/18 in the modulation of chemokines is very limited. Therefore, this study aimed to determine whether chemokines are differentially expressed in CC-derived cell lines; if E6/E7 oncoproteins from HPV16 and 18 are capable of mediating chemokine expression, what is the expression profile of chemokines in tissues derived from CC and what is their impact on the overall survival of patients with this pathology? For this purpose, RNA sequencing and real-time PCR were performed on SiHa, HeLa, and C33A tumorigenic cell lines, on the non-tumorigenic HaCaT cells, and the E6/E7 HPV-transduced HaCaT cell models. Furthermore, chemokine expression and survival analysis were executed on 304 CC and 22 normal tissue samples from The Cancer Genome Atlas (TCGA) repository. The results demonstrate that CXCL1, CXCL2, CXCL3, and CXCL8 are regulated by E6/E7 of HPV16 and 18, are overexpressed in CC biopsies, and that their higher expression is related to a worse prognostic survival.

Embedded Living HER2+ Cells in a 3D Gelatin-Alginate Hydrogel as an In Vitro Model for Immunotherapy Delivery for Breast Cancer.

Epidermal growth factor receptor 2 (HER2) is the second target molecule most commonly used in breast cancer treatment. Both recurrence and metastasis are still deadly for HER2+ breast cancer patients. Hydrogels can be an option for developing three-dimensional (3D) cell culture systems that resemble tumor features better than monolayer cultures and could be used for preclinical screening for new biotherapeutics. Biopolymers (gelatin and alginate) were used to develop a hydrogel capable of encapsulating living HER2+ breast cancer cells BT-474/GFP. The hydrogel was physicochemically characterized, and the viability of embedded cells was evaluated. The hydrogel developed had suitable physical properties, with swelling of 38% of its original mass at 20 h capacity and pore sizes between 20 and 125 µm that allowed cells to maintain their morphology in a 3D environment, in addition to being biocompatible and preserving 90% of cell viability at 10 days. Furthermore, encapsulated BT-474/GFP cells maintained HER2 expression that could be detected by the Trastuzumab-fluorescent antibody, so this hydrogel could be used to evaluate new HER2-targeted therapies.

A Ferrofluid with Surface Modified Nanoparticles for Magnetic Hyperthermia and High ROS Production.

A ferrofluid with 1,2-Benzenediol-coated iron oxide nanoparticles was synthesized and physicochemically analyzed. This colloidal system was prepared following the typical co-precipitation method, and superparamagnetic nanoparticles of 13.5 nm average diameter, 34 emu/g of magnetic saturation, and 285 K of blocking temperature were obtained. Additionally, the zeta potential showed a suitable colloidal stability for cancer therapy assays and the magneto-calorimetric trails determined a high power absorption density. In addition, the oxidative capability of the ferrofluid was corroborated by performing the Fenton reaction with methylene blue (MB) dissolved in water, where the ferrofluid was suitable for producing reactive oxygen species (ROS), and surprisingly a strong degradation of MB was also observed when it was combined with H2O2. The intracellular ROS production was qualitatively corroborated using the HT-29 human cell line, by detecting the fluorescent rise induced in 2,7-dichlorofluorescein diacetate. In other experiments, cell metabolic activity was measured, and no toxicity was observed, even with concentrations of up to 4 mg/mL of magnetic nanoparticles (MNPs). When the cells were treated with magnetic hyperthermia, 80% of cells were dead at 43 °C using 3 mg/mL of MNPs and applying a magnetic field of 530 kHz with 20 kA/m amplitude.

Green Metallic Nanoparticles for Cancer Therapy: Evaluation Models and Cancer Applications.

Metal-based nanoparticles are widely used to deliver bioactive molecules and drugs to improve cancer therapy. Several research works have highlighted the synthesis of gold and silver nanoparticles by green chemistry, using biological entities to minimize the use of solvents and control their physicochemical and biological properties. Recent advances in evaluating the anticancer effect of green biogenic Au and Ag nanoparticles are mainly focused on the use of conventional 2D cell culture and in vivo murine models that allow determination of the half-maximal inhibitory concentration, a critical parameter to move forward clinical trials. However, the interaction between nanoparticles and the tumor microenvironment is not yet fully understood. Therefore, it is necessary to develop more human-like evaluation models or to improve the existing ones for a better understanding of the molecular bases of cancer. This review provides recent advances in biosynthesized Au and Ag nanoparticles for seven of the most common and relevant cancers and their biological assessment. In addition, it provides a general idea of the in silico, in vitro, ex vivo, and in vivo models used for the anticancer evaluation of green biogenic metal-based nanoparticles.

Serum Analysis of Women with Early-Stage Breast Cancer Using a Mini-Array of Tumor-Associated Antigens.

Background: Several studies have shown that patients with cancer have antibodies in serum that react with cellular autoantigens, known as Tumor-Associated Antigens (TAA). The present work aimed to determine whether a mini-array comprising four recombinant TAA increases the detection of specific serum antibodies for the diagnosis of early-stage breast cancer. Methods: The mini-array included Alpha 1-AntiTrypsin (A1AT), TriosePhosphate Isomerase 1 (TPI1), Peptidyl-Prolyl cis-trans Isomerase A (PPIA), and PeroxiReDoXin 2 (PRDX2) full-length recombinant proteins. The proteins were produced after gene cloning, expression, and purification, and were verified by Western blot assays. Then, Dot-Blot was performed to find antibodies against the four TAA in 12 sera from women with early-stage breast cancer (stage II) and 12 sera from healthy women. Results: Antibody detection against individual TAA in early-stage breast cancer sera ranged from 58.3% to 83.3%. However, evaluation of the four TAA showed that there was a positive antibody reaction reaching a sensitivity of 100% and a specificity of 85% in early-stage breast cancer, suggesting that this mini-array must be evaluated as a clinical diagnostic tool for early-stage breast cancer in a larger sample size. Conclusion: Our results suggest that TAA mini-arrays may provide a promising and powerful method for improving the detection of breast cancer in Mexican women.

Molecular subtypes and clinicopathological features of breast cancer in Mexican women. / Subtipos moleculares y características clinicopatológicas de cáncer de mama en mujeres mexicanas.

BACKGROUND: Breast cancer is a multifactorial and heterogeneous disease with distinct molecular features and histopathologic subtypes involving different therapeutic responses and clinical outcomes. Classification of breast cancer in molecular subtypes has made possible an approach to develop therapeutic strategies in order to have a better understanding of the breast cancer development. Due to the heterogeneity of the disease, there are still features to be elucidated in the behavior, etiology and clinical outcomes of each molecular subtype in breast cancer. METHODS: Variables measured in 1,695 cases of invasive breast carcinoma were age, histopathological diagnosis, histopathological grade, expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), cell proliferation marker (Ki67) and basal cytokeratins (CK 5/6). P values were obtained using Chi square test and hazard ratios were calculated with 95% confidence intervals. RESULTS: An increase of aggressive molecular subtypes of breast cancer was observed. The mean age of incidence of breast cancer patients is decreasing, and breast cancer Patients younger than 40-years-old showed higher risk to exhibit Triple negative and Basal-like tumors. CONCLUSIONS: The mean age for this pathology is decreasing in our population and there is predominance in the differential occurrence of etiologically distinct entities of breast cancer affecting to the young women.

INTRODUCCIÓN: El cáncer de mama es una enfermedad heterogénea y multifactorial. Presenta distintas características clínicas, moleculares e histopatológicas, las cuales se asocian con la respuesta a los esquemas terapéuticos, así como al resultado clínico. La clasificación en subtipos moleculares (luminales, HER2, triple negativo y basales) ha permitido el desarrollo y aplicación de estrategias terapéuticas particulares. Sin embargo, dada la gran heterogeneidad de la enfermedad, existen aún características por elucidar en el comportamiento, etiología y resultados clínicos de cada subtipo molecular de cáncer de mama. MÉTODOS: Se obtuvieron datos de 1695 casos de cáncer de mama invasor. Se realizaron correlaciones entre las siguientes variables: edad, diagnóstico histopatológico, grado histológico, expresión del receptor de estrógenos (ER), receptor de progesterona (PR), receptor 2 del factor de crecimiento epidérmico humano (HER2), marcador de proliferación celular (Ki67) y citoqueratinas basales (CK 5/6). Los valores de p fueron calculados utilizando Chi cuadrada y el cociente de riesgo fue calculado con un intervalo de confianza de 95%. RESULTADOS: Se observó un incremento en la frecuencia de los subtipos moleculares más agresivos, así como una disminución en el valor de la media de la edad en las pacientes diagnosticadas con cáncer de mama. El análisis de la información indica que en pacientes menores de 40 años existe mayor riesgo a la presencia de tumores triple negativo o basales. CONCLUSIONES: En población mexicana, la media de edad para el diagnóstico primario de cáncer de está disminuyendo y hay mayor frecuencia de subtipos moleculares más agresivos en pacientes jóvenes.

An immunoconjugated up-conversion nanocomplex for selective imaging and photodynamic therapy against HER2-positive breast cancer.

Photodynamic therapy represents a very attractive therapeutic tool considered to be effective, minimally invasive and minimally toxic. However, conventional photodynamic therapy actually has two main constraints: the limited penetration depth of visible light needed for its activation, and the lack of selectivity. Considering this, this work reports the synthesis and evaluation of a novel nanoconjugate for imaging and selective photodynamic therapy against HER2-positive breast cancer, a particularly aggressive form of the disease. It was demonstrated that upon 975 nm near infrared light exposure, the red emission of the NaYF4:Yb,Er up-conversion nanoparticles (UCNPs) can be used for optical imaging and simultaneously represent the source for the excitation of a covalently bound zinc tetracarboxyphenoxy phthalocyanine (ZnPc), a photosensitizer that in turn transfers energy to ground state molecular oxygen to produce cytotoxic singlet oxygen. The specificity of our nanoconjugates was achieved by immunoconjugation with Trastuzumab (Tras), a specific monoclonal antibody for selective detection and treatment of HER2-overexpressing malignant breast cancer cells. Selective tracking of SKBR-3 HER2-positive cells was verified by confocal microscopy analysis, and the photodynamic therapy effect was considerably improved when Trastuzumab was incorporated into the nanoconjugate, the UCNPs-ZnPc-Tras being practically inert in the absence of infrared light exposure but reducing the HER2-positive cell viability up to 21% upon 5 min of the irradiation. This theranostic nanoconjugate represents a valuable alternative for HER2-positive breast cancer imaging and selective photodynamic therapy.

Characterization of B7H6, an endogenous ligand for the NK cell activating receptor NKp30, reveals the identity of two different soluble isoforms during normal human pregnancy.

B7H6, an endogenous ligand expressed on tumor cell surfaces, triggers NKp30-mediated activation of human NK cells. In contrast, the release of soluble B7H6 has been proposed as a novel mechanism by which tumors might evade NK cell-mediated recognition. Since NK cells are critical for the maintenance of early pregnancy, it is not illogical that soluble B7H6 might also be an important factor in directing NK cell activity during normal pregnancy. Thus, this study was focused on the characterization of soluble B7H6 during the development of normal pregnancy. Serum samples were obtained from healthy pregnant women who were experiencing their second pregnancies (n=36). Additionally, 17 of these pregnant participants were longitudinally studied for the presence of B7H6 during their second and third trimesters. Age-matched healthy non-pregnant women served as controls (n=30). The presence of soluble B7H6 was revealed by Western blotting. A further characterization was performed using an immunoproteomic approach based on 2DE-Western blotting combined with MALDI-MS. The results show that sera from all pregnant women were characterized by the presence of two novel isoforms of B7H6, both with lower MW than the reported of 51kDa. These isoforms were either a heavy (∼37kDa) or a light isoform (∼30kDa) and were mutually exclusive. N-glycosylation did not completely explain the different molecular weights exhibited by the two isoforms, as was demonstrated by enzymatic deglycosylation with PNGase F. The confirmation of the identity and molecular mass of each isoform indicates that B7H6, while maintaining the C- and N-termini, is most likely released during pregnancy by a mechanism distinct from proteolytic cleavage. We found that both isoforms, but mainly the heavier B7H6, were released via exosomes; and that the lighter isoform was also released in an exosome-free manner that was not observed in the heavy isoform samples. In conclusion, we find that soluble B7H6 is constitutively expressed during pregnancy and that, moreover, the soluble B7H6 is present in two new isoforms, which are released by exosomal and exosome-free mechanisms.

Porcine circovirus type 2 protective epitope densely carried by chimeric papaya ringspot virus-like particles expressed in Escherichia coli as a cost-effective vaccine manufacture alternative.

Porcine circovirus type 2 (PCV2) still represents a major problem to the swine industry worldwide, causing high mortality rates in infected animals. Virus-like particles (VLPs) have gained attention for vaccine development, serving both as scaffolds for epitope expression and immune response enhancers. The commercial subunit vaccines against PCV2 consist of VLPs formed by the self-assembly of PCV2 capsid protein (CP) expressed in the baculovirus vector system. In this work, a PCV2 protective epitope was inserted into three different regions of papaya ringspot virus (PRSV) CP, namely, the N- and C-termini and a predicted antigenic region located near the N-terminus. Wild-type and chimeric CPs were modeled in silico, expressed in Escherichia coli, purified, and visualized by transmission electron microscopy. This is the first report that shows the formation of chimeric VLPs using PRSV as epitope-presentation scaffold. Moreover, it was found that PCV2 epitope localization strongly influences VLP length. Also, the estimated yields of the chimeric VLPs at a small-scale level ranged between 65 and 80 mg/L of culture medium. Finally, the three chimeric VLPs induced high levels of immunoglobulin G against the PCV2 epitope in immunized BALB/c mice, suggesting that these chimeric VLPs can be used for swine immunoprophylaxis against PCV2.

Colostrum proinflammatory cytokines as biomarkers of bovine immune response to bovine tuberculosis (bTB).

Bovine colostrum contains compounds, which provide passive immune protection from mother to newborn calves. Little is known about cytokine levels and their role in bovine colostrum. Moreover, the capacity of bovine colostrum cells to mount specific immune responses after natural exposure to bovine tuberculosis (bTB) antigens in dairy herds has not been studied, thus far. The purpose of this study was to identify biomarkers for bTB infection measurable in bovine colostrum. The present study reveals that isolated-immune colostrum cells can mount a specific immune response against bTB antigens, by measuring the novo IFN-γ release in cell culture. We found that IFN-γ levels in the responders (Bov+) to bTB antigen were higher than in non-responders (Bov-). On the other hand, proinflammatory cytokines contained in colostrum's whey were tested in Tuberculin Skin Test (TST) reactor (TST+) and non-reactor (TST-) animals to assess their potential role as biomarker. We observed that IFN-γ levels were lower or undetectable, as opposed to IL4 levels were measurable, the TNF-α level was higher in TST- than TST+, while IL-6 levels showed the opposite reaction and with no statistical significance. Moreover, IL-1α mRNA expression levels were higher in colostrum mononuclear cells (CMC) in Bov+ cattle. Collectively, these data suggest that the differential expression of pro and anti-inflammatory cytokines could have relevant value to diagnose bTB in cattle.

Self-assembly of hexahistidine-tagged tobacco etch virus capsid protein into microfilaments that induce IgG2-specific response against a soluble porcine reproductive and respiratory syndrome virus chimeric protein.

BACKGROUND: Assembly of recombinant capsid proteins into virus-like particles (VLPs) still represents an interesting challenge in virus-based nanotechnologies. The structure of VLPs has gained importance for the development and design of new adjuvants and antigen carriers. The potential of Tobacco etch virus capsid protein (TEV CP) as adjuvant has not been evaluated to date. FINDINGS: Two constructs for TEV CP expression in Escherichia coli were generated: a wild-type version (TEV-CP) and a C-terminal hexahistidine (His)-tagged version (His-TEV-CP). Although both versions were expressed in the soluble fraction of E. coli lysates, only His-TEV-CP self-assembled into micrometric flexuous filamentous VLPs. In addition, the His-tag enabled high yields and facilitated purification of TEV VLPs. These TEV VLPs elicited broader IgG2-specific antibody response against a novel porcine reproductive and respiratory syndrome virus (PRRSV) protein when compared to the potent IgG1 response induced by the protein alone. CONCLUSIONS: His-TEV CP was purified by immobilized metal affinity chromatography and assembled into VLPs, some of them reaching 2-µm length. TEV VLPs administered along with PRRSV chimeric protein changed the IgG2/IgG1 ratio against the chimeric protein, suggesting that TEV CP can modulate the immune response against a soluble antigen.

Identification of immunogenic proteins from ovarian tissue and recognized in larval extracts of Rhipicephalus (Boophilus) microplus, through an immunoproteomic approach.

Rhipicephalus (Boophilus) microplus ticks are obligatory hematophagous ectoparasites of cattle and act as vectors for disease-causing microorganisms. Conventional tick control is based on the use of chemical acaricides; however, their uncontrolled use has increased tSresistant tick populations, as well as food and environmental contamination. Alternative immunological tick control has shown to be partially effective. The only anti-tick vaccine commercially available at present in the world is based on intestinal Bm86 protein, and shows a variable effectiveness depending on tick strains or geographic isolates. Therefore, there is a need to characterize new antigens in order to improve immunological protection. The aim of this work was to identify immunogenic proteins from ovarian tissue extracts of R. microplus, after cattle immunization. Results showed that ovarian proteins complexed with the adjuvant Montanide ISA 50 V generated a strong humoral response on vaccinated cattle. IgG levels peaked at fourth post-immunization week and remained high until the end of the experiment. 1D and 2D SDS-PAGE-Western blot assays with sera from immunized cattle recognized several ovarian proteins. Reactive bands were cut and analyzed by LC-MS/MS. They were identified as Vitellogenin, Vitellogenin-2 precursor and Yolk Cathepsin. Our findings along with bioinformatic analysis indicate that R. microplus has several Vitellogenin members, which are proteolytically processed to generate multiple polypeptide fragments. This apparent complexity of vitellogenic tick molecular targets gives the opportunity to explore their potential usefulness as vaccine candidates but, at the same time, imposes a challenge on the selection of the appropriate set of antigens.

Identification of immunodominant proteins from Mannheimia haemolytica and Histophilus somni by an immunoproteomic approach.

Mannheimia haemolytica and Histophilus somni are frequently isolated from diseased cattle with bovine respiratory disease (BRD). They compromise animal lung function and the immune responses generated are not sufficient to limit infection. Identification of specific immunogenic antigens for vaccine development represents a great challenge. Immunogenic proteins were identified by immunoproteomic approach with sera from cattle immunized with a commercial cellular vaccine of M. haemolytica and H. somni. Proteins of M. haemolytica were identified as solute ABC transporter, iron-binding protein, and hypothetical protein of capsular biosynthesis. Histophilus somni proteins correspond to porin, amino acid ABC transporter, hypothetical outer membrane protein, cysteine synthase, and outer membrane protein P6. Although these antigens share strong similarities with other proteins from animal pathogens, the ABC system proteins have been associated with virulence and these proteins could be considered as potential vaccine candidates for BRD.

Mannheimia haemolytica et Histophilus somni sont fréquemment isolées de bovins atteints de maladies respiratoires bovines (MRB). Ces agents compromettent la fonction pulmonaire et les réponses immunitaires générées ne permettent pas de limiter l'infection. L'identification d'antigènes spécifiques et immunogènes qui permettraient le développement de vaccins, représente un grand défi actuellement. Les protéines immunogènes ont été identifiées par une approche immunoproteomique en utilisant des sérums provenant de bovins immunisés par des vaccins commerciaux de M. haemolytica et H. somni. Les protéines de M. haemolytica ont été identifiées comme étant un transporteur ABC, une protéine de liaison du fer et une hypothétique protéine impliquée dans la biosynthèse de la capsule. Celles de H. somni correspondent à une porine, à un transporteur ABC d'acides aminés, à une hypothétique protéine de membrane externe, à la cystéine synthase et à la protéine membranaire P6. Bien que ces antigènes présentent une forte homologie avec des protéines provenant d'autres pathogènes d'animaux, les protéines du système ABC sont associées à la virulence et pourraient être considérées comme des candidats potentiels pour l'élaboration de vaccins contre les MBR.(Traduit par Docteur Patricia Dupre).

The adenylyl cyclase Rv2212 modifies the proteome and infectivity of Mycobacterium bovis BCG.

All organisms have the capacity to sense and respond to environmental changes. These signals often involve the use of second messengers such as cyclic adenosine monophosphate (cAMP). This second messenger is widely distributed among organisms and coordinates gene expression related with pathogenesis, virulence, and environmental adaptation. Genomic analysis in Mycobacterium tuberculosis has identified 16 adenylyl cyclases (AC) and one phosphodiesterase, which produce and degrade cAMP, respectively. To date, ten AC have been biochemically characterized and only one (Rv0386) has been found to be important during murine infection with M. tuberculosis. Here, we investigated the impact of hsp60-driven Rv2212 gene expression in Mycobacterium bovis Bacillus Calmette-Guerin (BCG) during growth in vitro, and during macrophage and mice infection. We found that hsp60-driven expression of Rv2212 resulted in an increased capacity of replication in murine macrophages but an attenuated phenotype in lungs and spleen when administered intravenously in mice. Furthermore, this strain displayed an altered proteome mainly affecting proteins associated with stress conditions (bfrB, groEL-2, DnaK) that could contribute to the attenuated phenotype observed in mice.

Molecular cloning and characterization of a glycine-like receptor gene from the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

The cattle tick Rhipicephalus (Boophilus) microplus is the most economically important ectoparasite affecting the cattle industry in tropical and subtropical areas around the world. The principal method of tick control has relied mainly on the use of chemical acaricides, including ivermectin; however, cattle tick populations resistant to ivermectin have recently been reported in Brazil, Mexico, and Uruguay. Currently, the molecular basis for ivermectin susceptibility and resistance are not well understood in R. microplus. This prompted us to search for potential molecular targets for ivermectin. Here, we report the cloning and molecular characterization of a R. microplus glycine-like receptor (RmGlyR) gene. The characterized mRNA encodes for a 464-amino acid polypeptide, which contains features common to ligand-gated ion channels, such as a large N-terminal extracellular domain, four transmembrane domains, a large intracellular loop and a short C-terminal extracellular domain. The deduced amino acid sequence showed around 30% identity to GlyRs from some invertebrate and vertebrate organisms. The polypeptide also contains the PAR motif, which is important for forming anion channels, and a conserved glycine residue at the third transmembrane domain, which is essential for high ivermectin sensitivity. PCR analyses showed that RmGlyR is expressed at egg, larval and adult developmental stages. Our findings suggest that the deduced receptor is an additional molecular target to ivermectin and it might be involved in ivermectin resistance in R. microplus.

Functional properties of Ditaxis heterantha proteins.

Ditaxis heterantha is a plant of the Euphorbiaceae family that grows in semiarid regions of Mexico. It produces yellow pigmented seeds that are used for coloring of foods. The seeds contain about 20% of proteins. Proteins of D. heterantha were extracted and fractionated on the basis of solubility. Three main protein fractions were obtained: glutelins, 488 ± 0.5; albumins, 229 ± 2; and total globulins, 160 ± 1 g/kg. The amino acid profile was evaluated for each fraction and protein isolated, where the protein isolate contains essential amino acids such as Val, Phe, Tyr, and Leu. A calorimetric study showed that globulins and glutelins have a high denaturing temperature between 100 and 106°C, while albumins showed a denaturing temperature at 76°C. The protein isolate and its fractions exhibited functional properties: the isolated protein demonstrated good oil-holding capacity of 40.7 g/kg. Foam capacity (FC) and foam stability (FS) were observed principally in glutelins and globulins where FC maximum was 330% and the FS was 28 min. The emulsifying capacity was observed in the same fractions of glutelins and globulins, followed by albumins. However, the glutelin fraction in particular was the only fraction that exhibited emulsifying stability at pH 5, 6, and 7. Gelling capacity was observed in albumins and globulins. This study indicated that protein isolated from D. heterantha could be used in food formulations due to its essential amino acid profile. Glutelin could be used as an emulsifying additive. Additionally, glutelin and globulin were stable at temperatures above 100°C; this is an important factor in food industry, principally in heat processes.

Alpha 1-antitrypsin: a novel tumor-associated antigen identified in patients with early-stage breast cancer.

Several studies have demonstrated that sera from patients with cancer contain antibodies that recognize a unique group of autologous antigens called tumor-associated antigens (TAA). In the current study, we employed an immunoproteomic approach, combining 2DE, Western blot, and MALDI-MS to identify TAA in the sera of patients diagnosed with infiltrating ductal or in situ carcinoma breast cancer. Sera obtained from 25 newly diagnosed patients with stage II breast cancer and 20 healthy volunteers was evaluated for the presence of novel TAA. Alpha 1-antitrypsin (A1AT) antibodies were detected in 24 of 25 patients with breast cancer (96%) and in 2 of 20 controls (10%). Sensitivity of detection of autoantibodies against A1AT in patients with breast cancer was 96%. Our preliminary results suggest that A1AT and autoantibodies against alpha 1 antitrypsin may be useful serum biomarkers for early-stage breast cancer screening and diagnosis.

Identification of immunodominant antigens of Mycobacterium bovis by expression library immunization.

This study combines two methodologies - vector expression of a genomic library and proteomics - to identify immunogenic proteins of Mycobacterium bovis. Immunization of BALB/c mice with a plasmid DNA pool from the library, containing approximately 8000 clones, induced a humoral response that facilitated the detection of 12 antigenic proteins by Western blotting. Two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry identified four proteins (Cpn60-1, HSP70, EF-Tu, and AdoHcyase). Such genomic immunization offers the possibility of in vivo screening of potential candidate M. bovis antigens.

Acaricidal effect and chemical composition of essential oils extracted from Cuminum cyminum, Pimenta dioica and Ocimum basilicum against the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

Acaricidal activity of essential oils extracted from cumin seeds (Cuminum cyminum), allspice berries (Pimenta dioica) and basil leaves (Ocimum basilicum) were tested on 10-day-old Rhipicephalus (Boophilus) microplus tick larvae using the LPT. Two-fold dilutions of the three essential oils were tested from a starting dilution of 20% down to 1.25%. Results showed a high toxicological effect for cumin, producing 100% mortality in all tested concentrations on R. microplus larvae. Similarly, allspice essential oil produced 100% mortality at all concentrations with the exception of a dramatic decrease at 1.25% concentration. Conversely, basil essential oil was not shown to be toxic against R. microplus larvae. The most common compounds detected by gas chromatography-mass spectrometry were as follows: cumin: cuminaldehyde (22.03%), γ-terpinene (15.69%) and 2-caren-10-al (12.89%); allspice: methyl eugenol (62.7%) and eugenol (8.3%); basil: linalool (30.61%) and estragole (20.04%). Results clearly indicate that C. cyminum and P. dioica essential oils can be used as an effective alternative for R. microplus tick control, and there is a high probability they can be used for other ticks affecting cattle in Mexico and throughout the world, thereby reducing the necessity for traditional and unfriendly synthetic acaricides.