Variation of the 2D Pattern of Brain Proteins in Mice Infected with Taenia crassiceps ORF Strain.

Some parasites are known to influence brain proteins or induce changes in the functioning of the nervous system. In this study, our objective is to demonstrate how the two-dimensional gel technique is valuable for detecting differences in protein expression and providing detailed information on changes in the brain proteome during a parasitic infection. Subsequently, we seek to understand how the parasitic infection affects the protein composition in the brain and how this may be related to changes in brain function. By analyzing de novo-expressed proteins at 2, 4, and 8 weeks post-infection compared to the brains of the control mice, we observed that proteins expressed at 2 weeks are primarily associated with neuroprotection or the initial response of the mouse brain to the infection. At 8 weeks, parasitic infection can induce oxidative stress in the brain, potentially activating signaling pathways related to the response to cellular damage. Proteins expressed at 8 weeks exhibit a pattern indicating that, as the host fails to balance the Neuro-Immuno-Endocrine network of the organism, the brain begins to undergo an apoptotic process and consequently experiences brain damage.

Differential Protein Expression of Taenia crassiceps ORF Strain in the Murine Cysticercosis Model Using Resistant (C57BL/6) Mice.

A cysticercosis model of Taenia crassiceps ORF strain in susceptible BALB/c mice revealed a Th2 response after 4 weeks, allowing for the growth of the parasite, whereas resistant C57BL/6 mice developed a sustained Th1 response, limiting parasitic growth. However, little is known about how cysticerci respond to an immunological environment in resistant mice. Here, we show that the Th1 response, during infection in resistant C57BL/6 mice, lasted up to 8 weeks and kept parasitemia low. Proteomics analysis of parasites during this Th1 environment showed an average of 128 expressed proteins; we chose 15 proteins whose differential expression varied between 70 and 100%. A total of 11 proteins were identified that formed a group whose expression increased at 4 weeks and decreased at 8 weeks, and another group with proteins whose expression was high at 2 weeks and decreased at 8 weeks. These identified proteins participate in tissue repair, immunoregulation and parasite establishment. This suggests that T. crassiceps cysticerci in mice resistant under the Th1 environment express proteins that control damage and help to establish a parasite in the host. These proteins could be targets for drugs or vaccine development.

Proteomic analysis of IgM antigens from mammary tissue under pre- and post-cancer conditions using the MMTV-PyVT mouse model.

We analyzed the recognition of tumor antigens by IgM in transgenic MMTV-PyVT mice. PyVT female mice are a model of breast cancer that simulates its counterpart in humans. The PyVT model allows studying antigen recognition in two conditions: before and during tumor expression. We attempted to identify by sequence, the antigens recognized by IgM that are expressed or disappear in the membrane of breast transgenic tissue during the transition "No tumor-Tumor". 2D immunoblots were obtained of isolated membranes from the breast tissue in the fifth, sixth, and seventh week (transition point). Proteins recognized by IgM were sequenced in duplicate by MALDI-TOF. In the transition, we observed the disappearance of antigens in transgenic mice with respect to non-transgenic ones. We believe that in the diagnosis of cancer in its early stages, the expression of early antigens is as important as their early delocalization, with the latter having the advantage that, under normal conditions, we can know which proteins should be present at a given time. Therefore, we could consider that also the absence of antigens could be considered as a biomarker of cancer in progress.

Protection induced by estradiol benzoate in the MPP+ rat model of Parkinson's disease is associated with the regulation of the inflammatory cytokine profile in the nigro striatum.

Previously, we have demonstrated that ß-estradiol-3-benzoate (EB) has a protective effect on the neurodegenerative experimental model of Parkinson's disease. The protective effect is through the induction of the expression of paraoxonase-2 (PON2) in the striatum. PON2 has proven to have antioxidant and anti-inflammatory activity, this protein has a beneficial effect in MPP+ model in rats decreasing the lipid peroxidation and the oxidative stress. Furthermore, the molecular effect and the pathway by which EB induces protection were not further pursued. This study shows the regulation by EB of the anti-inflammatory effect through the modulation of cytokines, antioxidant enzymes and PON2 in the rat striatum. Rats were gonadectomized and 30 days after were randomly assigned into four experimental groups; only vehicles (Control group); EB treatment (EB group); MPP+ injury (M group); EB plus MPP+ injured (EB/M group). EB treatment consisted of 100 µg of the drug administered every 48 h for 11 days. Results showed that EB (group EB/M) treatment decrease significantly (40%) the number of ipsilateral turns respect to the M group and prevents significantly the dopamine (DA) decreased induced by MPP+ (~75%). This results are correlate with a significant decrease in the level of lipid peroxidation (60%) of the EB/M group respect to the M group. The EB treatment showed protection against neurotoxicity induced with MPP+, this could be due to EB capacity to prevent the increase in the expression level of proinflammatory cytokines TNF-α, IL-1 and IL-6 induced by MPP+. While, TGF-ß1 and TGF-ß3 expression was reduced in the rats treated only with MPP+, in the rats of EB/M group the expression of both cytokines was increased. EB protective effect against MPP+ neurotoxicity is related to antioxidant effect of PON2, pro-inflammatory cytokines and GSHR but not to SOD2, catalase, GPX1 or GPX4.

Protein expression profile of Taenia crassiceps cysticerci related to Th1- and Th2-type responses in the mouse cysticercosis model.

The intraperitoneal cysticercosis model with the Taenia crassiceps ORF strain in female BALB/cAnN mice has been widely used to study the immune response in cysticercosis. During early infection (2 weeks), the host develops a non-permissive Th1 response, whereas during late infection (8 weeks), molecules from the cysticerci induce a Th2 response that is permissive to parasite growth. The modulation of the Th2 response is induced by molecules excreted/secreted by the larval stage of the parasite. However, there is limited information regarding the response of cysticerci to the mouse immunological environment during infection. The proteomic profiles in T. crassiceps ORF cysticerci when faced with the mouse Th1 and Th2 responses were analyzed through two-dimensional gel electrophoresis (2DE), and the differential expression of proteins was evaluated. Thirteen proteins, whose differential expression varied between 70% and 100%, were selected randomly. Protein identification by MALDI-TOF MS and BLAST showed that the proteins were related to folding, signaling, enzymatic activities, cell-movement regulation, cell-cell interactions, motility, carbohydrate metabolism, detoxification, and redox regulation processes. Notably, some of the proteins can act as antigenic-protective molecules and elicit a weak Th1 response; however, most are involved in the avoidance of the immune system, which leads to a Th2 response, or apoptosis. The findings indicate the process by which T. crassiceps cysticerci responds based on the host environment and provides novel insights into the mechanism by which this facilitates its establishment and persistence in the mouse. Furthermore, these proteins could be used as targets for drug and vaccine development.

ß-Estradiol-3-benzoate confers neuroprotection in Parkinson MPP+ rat model through inhibition of lipid peroxidation.

Estradiol (E2), in addition to its known hormone function, is a neuroactive steroid that has shown neuroprotective profile in several models of neurological diseases. The present study explores the antioxidant effect of ß-estradiol-3-benzoate (EB) on the neurotoxicity elicited by MPP+ in rat striatum. Male Wistar rats, that were gonadectomized 30days prior to EB, were given 100µgEB per rat every 48h for 11days and animals were infused with MPP+ via intrastriatal at day six after beginning EB treatment. EB treatment completely prevented the fall in dopamine caused by MPP+, such result was related with decreased lipid peroxidation, a marker of oxidative stress; diminished number of ipsilateral-to-lesion turns and increased signal of the dopamine-synthesizing enzyme Tyrosin Hydroxylase in substantia nigra. The protection elicited by EB was not related to Mn or Cu-Zn superoxide dismutase enzymatic activities or glutathione modulation since none of these parameters were influenced by EB at the times assayed. Whereas, increased expression of PON2 as a result of EB treatment was observed, this phenomenon could be one of the mechanism by which the steroid conferred protection to dopaminergic cells against MPP+ injury.

Recognition of tumor antigens in 4T1 cells by natural IgM from three strains of mice with different susceptibilities to spontaneous breast cancer.

The issue of antibody responses to tumors is potentially important to cancer immunologists. Early detection of cancer represents one of the most promising approaches to reduce the growing cancer burden. Natural immunoglobulin (Ig)M antibodies have been associated with the recognition and elimination of cancerous and precancerous cells. Using natural IgM antibodies, the present study identified a set of antigens in healthy mice from three different strains and examined whether the global patterns of antibodies are able to discriminate between a condition of more or less susceptibility to breast cancer. The current study performed two-dimensional (2D) immunoblotting to detect antigens from 4T1 cells using natural IgM from serum of healthy female mice from three different strains. The t-test was used to analyze the total number of spots. There were no significant differences in the numbers of antigens recognized in each strain. However, differences in patterns were observed on 2D immunoblots among the three strains. The reactivity patterns of natural IgM antibodies to particular antigens exhibited non-random clustering, which discriminated between strains with different susceptibilities to spontaneous breast cancer. The results demonstrated that the patterns of reactivity to defined subsets of antigens are able to provide information regarding differential diagnosis associated with breast cancer sensitivity. Therefore, it may be concluded that it is possible to segregate the IgM humoral immune response toward cancer antigens according to the genetic background of individuals. In addition, it is possible to identify the recognized antigens that allow grouping or discriminate between the different IgM antibodies expressed. The possible association between a particular antigen and cancer susceptibility requires further study, but the methodology exposed in the present study may identify potential candidates for this possible association.

Natural and adaptive IgM antibodies in the recognition of tumor-associated antigens of breast cancer (Review).

For early detection of cancer, education and screening are important, but the most critical factor is the development of early diagnostic tools. Methods that recognize the warning signs of cancer and take prompt action lead to an early diagnosis; simple tests can identify individuals in a healthy population who have the disease but have not developed symptoms. Early detection of cancer is significant and is one of the most promising approaches by which to reduce the growing cancer burden and guide curative treatment. The early diagnosis of patients with breast cancer is challenging, since it is the most common cancer in women worldwide. Despite the advent of mammography in screening for breast cancer, low-resource, low-cost alternative tools must be implemented to complement mammography findings. IgM is part of the first line of defense of an organism and is responsible for recognizing and eliminating infectious particles and removing transformed cells. Most studies on breast cancer have focused on the development of IgG-like molecules as biomarkers or as a treatment for the advanced stages of cancer, but autoantibodies (IgM) and tumor-associated antigens (proteins or carbohydrates with aberrant structures) have not been examined as early diagnostic tools for breast cancer. The present review summarizes the function of natural and adaptive IgM in eliminating cancer cells in the early stages of pathology and their value as early diagnostic tools. IgM, as a component of the immune system, is being used to identify tumor-associated antigens and tumor-associated carbohydrate antigens.

Comparison patterns of 4 T1 antigens recognized by humoral immune response mediated by IgG and IgM antibodies in female and male mice with breast cancer using 2D-immnunoblots.

The early detection of cancer is one of the most promising approaches to reduce its growing burden and develop a curative treatment before the tumor is established. The early diagnosis of breast cancer is the most demanding of all tumors, because it is the most common cancer in women worldwide. We have described a new approach to analyze humoral immune reactions against 4 T1 cell antigens in female mice, reporting that the IgG and IgM responses differed and varied over time and between individuals. In this study, we compared and analyzed the detection of tumor antigens with IgG and IgM from the sera of male mice that were injected with 4 T1 cells into the mammary gland nipple in 2D immunoblot images. The variability in IgM and IgG responses in female and male mice with breast cancer at various stages of disease was characterized, and the properties with regard to antigen recognition were correlated statistically with variables that were associated with the individuals and tumors. The ensuing IgG and IgM responses differed. Only the IgG response decreased over time in female mice--not in male mice. The IgM response was maintained during tumor development in both sexes. Each mouse had a specific pattern of antigen recognition--ie, an immunological signature--represented by a unique set of antigen spots that were recognized by IgM or IgG. These data would support that rationale IgM is a better tool for early diagnosis, because it is not subject to immunosuppression like IgG in female mice with breast cancer.

Mechanisms associated with resistance to tamoxifen in estrogen receptor-positive breast cancer (review).

Anti-estrogens such as tamoxifen are widely used in the clinic to treat estrogen receptor-positive breast tumors. Patients with estrogen receptor-positive breast cancer initially respond to treatment with anti-hormonal agents such as tamoxifen, but remissions are often followed by the acquisition of resistance and, ultimately, disease relapse. The development of a rationale for the effective treatment of tamoxifen-resistant breast cancer requires an understanding of the complex signal transduction mechanisms. In the present study, we explored some mechanisms associated with resistance to tamoxifen, such as pharmacologic mechanisms, loss or modification in estrogen receptor expression, alterations in co-regulatory proteins and the regulation of the different signaling pathways that participate in different cellular processes such as survival, proliferation, stress, cell cycle, inhibition of apoptosis regulated by the Bcl-2 family, autophagy, altered expression of microRNA, and signaling pathways that regulate the epithelial-mesenchymal transition in the tumor microenvironment. Delineation of the molecular mechanisms underlying the development of resistance may aid in the development of treatment strategies to enhance response and compromise resistance.

2D immunoblots show differential response of mouse IgG and IgM antibodies to antigens of mammary carcinoma 4 T1 cells.

BACKGROUND: Immunosuppression in breast cancer has been reported in women and in the highly metastatic mouse mammary tumor model 4 T1. The immunosuppressive environment complicates the use of the humoral response against the tumor as an immunodiagnostic tool. IgM has not been used in immunodiagnostic in part because its antitumor responses, both innate and adaptive, have not been studied in function of time in breast cancer.We show a new approach to analyzing the mouse humoral immune response, and compare the evolution with time of IgG and IgM responses against the antigens of 4 T1 cells. METHODS: The study is based on 2-dimensional immunoblotting detection of antigens from 4 T1 cells by the IgG and IgM antibodies in the serum of female mice injected with 4 T1 cells. RESULTS: There was a high variability in the intra-and inter-mouse response. Variability in the IgM response was manifested as a pattern of spots that could become a multibinomial variable of 0 and 1, which could represent a signature of the immune response. Different numbers of spots was found in the IgG and IgM responses from week 1 to 5. On average, the IgM had more but the IgG response decrease with the time. The natural IgM at t = 0 responds stronger than w1; the adaptive response of both IgM and IgG were elicited where, with the former being stronger better than the latter. Antigens that are recognized by some female mice in the first week are also recognized by other female mice at time 0. Contamination of the natural IgM makes difficult use the adaptive IgM as a tool for immunodiagnostic. CONCLUSIONS: IgM and IgG response varied with the time and individuals. Spot variation in 2D pattern for the natural IgM could be expressed as a binomial signature, which opens up the way to correlate a particular pattern with resistance or susceptibility. This uncovers a battery of IgMs for each individual to confront cancer or infections. The possibility to differentiate between adaptive IgM antibodies from the natural IgM will allow investigation of the adaptive IgM for early immunodiagnosis.