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.

Genome-Wide Association Study in Mexican Holstein Cattle Reveals Novel Quantitative Trait Loci Regions and Confirms Mapped Loci for Resistance to Bovine Tuberculosis.

Bovine tuberculosis (bTB) is a disease of cattle that represents a risk to public health and causes severe economic losses to the livestock industry. Recently, genetic studies, like genome-wide association studies (GWAS) have greatly improved the investigation of complex diseases identifying thousands of disease-associated genomic variants. Here, we present evidence of genetic variants associated with resistance to TB in Mexican dairy cattle using a case-control approach with a selective DNA pooling experimental design. A total of 154 QTLRs (quantitative trait loci regions) at 10% PFP (proportion of false positives), 42 at 5% PFP and 5 at 1% PFP have been identified, which harbored 172 annotated genes. On BTA13, five new QTLRs were identified in the MACROD2 and KIF16B genes, supporting their involvement in resistance to bTB. Six QTLRs harbor seven annotated genes that have been previously reported as involved in immune response against Mycobacterium spp: BTA (Bos taurus autosome) 1 (CD80), BTA3 (CTSS), BTA 3 (FCGR1A), BTA 23 (HFE), BTA 25 (IL21R), and BTA 29 (ANO9 and SIGIRR). We identified novel QTLRs harboring genes involved in Mycobacterium spp. immune response. This is a first screening for resistance to TB infection on Mexican dairy cattle based on a dense SNP (Single Nucleotide Polymorphism) chip.

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.

Mycobacterium bovis DNA detection in colostrum as a potential indicator of vaccination effectiveness against bovine tuberculosis.

Bovine tuberculosis (bTB) remains a problem on many dairy farms in Mexico, as well as a public health risk. We previously found a high frequency of Mycobacterium bovis DNA in colostrum from dairy cows using a nested PCR to detect mpb70. Since there are no reliable in vivo tests to determine the effectiveness of booster Mycobacterium bovis BCG vaccination against bTB, in this work we monitored M. bovis DNA in colostrum by using this nested PCR. In order to decrease the risk of adverse reactions in animals likely containing viable M. bovis, a single application of BCG and a subunit vaccine (EEP-1) formulated with M. bovis culture filtrate proteins (CFP) and a copolymer as the adjuvant was performed in tuberculin skin test-negative cattle (TST(-)), while TST reactor animals (TST(+)) received EEP-1 only. Booster immunization using EEP-1 was applied to both groups, 2 months after primary vaccination to whole herds and 12 months later to lactating cows. Colostrum samples were collected from 6 farms where the cows were vaccinated over a 12-month period postvaccination and, for comparison, from one control farm where the cows were not vaccinated with comparable bTB prevalence. We observed an inverse relationship between the frequency of M. bovis DNA detection and time postvaccination at the first (P < 0.001) and second (P < 0.0001) 6-month periods. Additionally, the concentration of gamma interferon (IFN-γ) was higher in mpb70 PCR-positive colostrum samples (P = 0.0003). These results suggest that M. bovis DNA frequency in colostrum could be a potentially useful biomarker for bTB vaccine efficacy on commercial dairy farms.