Equol (7-hydroxy-3[4'hydroxyphenyl]-chroman) is the major metabolite of the phytoestrogen daidzein, one of the main isoflavones found abundantly in soybeans and soy foods. Equol may be an important biologically active molecule based on recent studies demonstrating that equol can modulate reproductive function. In this study, we examined the effects of equol on prostate growth and LH secretion and determined some of the mechanisms by which it might act. Administration of equol to intact male rats for 4-7 days reduced ventral prostate and epididymal weight and increased circulating LH levels. Using binding assays, we determined that equol specifically binds 5alpha-dihydrotestosterone (DHT), but not testosterone, dehydroepiandrosterone, or estrogen with high affinity. Equol does not bind the prostatic androgen receptor, and has a modest affinity for recombinant estrogen receptor (ER) beta, and no affinity for ERalpha. In castrated male rats treated with DHT, concomitant treatment with equol blocked DHT's trophic effects on the ventral prostate gland growth and inhibitory feedback effects on plasma LH levels without changes in circulating DHT. Therefore, equol can bind circulating DHT and sequester it from the androgen receptor, thus altering growth and physiological hormone responses that are regulated by androgens. These data suggest a novel model to explain equol's biological properties. The significance of equol's ability to specifically bind and sequester DHT from the androgen receptor have important ramifications in health and disease and may indicate a broad and important usage for equol in the treatment of androgen-mediated pathologies.
The hormonal response to stress is enhanced by oestrogen but inhibited by androgens. To determine underlying changes in activity of neuropeptide neurones in the paraventricular nucleus of the hypothalamus (PVN), we examined the effect of oestrogen and androgen treatment on restraint-induced c-fos mRNA, corticotropin-releasing hormone (CRH) heteronuclear RNA, and arginine vasopressin hnRNA expression in the PVN. Male rats were gonadectomized and injected with oestradiol benzoate (EB) or dihydrotestosterone propionate (DHTP; s.c., daily for 4 days). Rats were stressed by restraint for 10 min or 30 min before killing. Other rats were stressed for 30 min and then returned to their home cage for 20 min before killing. Corticosterone and adrenocorticotropic hormone responses to restraint stress were signi®cantly greater in EB-treated rats and lower in DHTP-treated rats at the 30-min timepoint compared to controls. c-fos mRNA increases following stress were augmented by EB but inhibited by DHTP. CRH hnRNA expression increased signi®cantly in the PVN in response to restraint stress, and this increase was augmented by EB treatment, but decreased by DHTP treatment. Vasopressin hnRNA expression was also increased in response to stress, and this increase was attenuated by DHTP. These ®ndings indicate that gonadal hormones in¯uence the reactivity of the hypothalamic-pituitary adrenal axis to stress.Stressful events, either actual or perceived, activate neurones within the paraventricular nucleus (PVN) of the hypothalamus, resulting in the enhanced synthesis and secretion of hypothalamic neuropeptides (1±3). The major secretogogues regulating the hypothalamic-pituitary adrenal axis (HPA axis) are corticotopin-releasing hormone (CRH) and arginine vasopressin. These neuropeptides can subsequently act alone or in concert to stimulate the synthesis and release of adrenocorticotropic hormone (ACTH) from anterior pituitary corticotrophs. ACTH drives adrenal cortical hormone secretion. HPA axis activity is subsequently terminated by negative feedback in which the major inhibitory tone comes from circulating corticosterone.There exists a sex difference in HPA function due at least in part to circulating sex steroid hormones (1±3). When stressed, females display a more robust HPA response than males (1±5). It appears that, in males, androgens act to inhibit (3±5) whereas, in females, oestrogens function to enhance (1±3) the activity of the HPA axis. This is in contrast to behavioural responses to stress where oestrogen appears to reduce fear related behaviour, but androgens enhance their appearance (2).Endocrine manipulation studies in females show that ovariectomy can reduce the stress-induced secretion of ACTH and corticosterone. This can be reversed via oestrogen administration (1±3). However, the precise mechanisms by which oestrogen enhances levels of ACTH and corticosterone are not completely understood. Some evidence indicates that oestrogen directly in¯uences cellular activity and gene expression within neurosecretory neurones ...
Infiltration of T cells in breast tumors correlates with improved survival of patients with breast cancer, despite relatively few mutations in these tumors. To determine if T-cell specificity can be harnessed to augment immunotherapies of breast cancer, we sought to identify the alpha-beta paired T-cell receptors (TCRs) of tumor-infiltrating lymphocytes shared between multiple patients. Because TCRs function as heterodimeric proteins, we used an emulsion-based RT-PCR assay to link and amplify TCR pairs. Using this assay on engineered T-cell hybridomas, we observed ∼85% accurate pairing fidelity, although TCR recovery frequency varied. When we applied this technique to patient samples, we found that for any given TCR pair, the dominant alpha-or beta-binding partner comprised ∼90% of the total binding partners. Analysis of TCR sequences from primary tumors showed about fourfold more overlap in tumor-involved relative to tumor-free sentinel lymph nodes. Additionally, comparison of sequences from both tumors of a patient with bilateral breast cancer showed 10% overlap. Finally, we identified a panel of unique TCRs shared between patients' tumors and peripheral blood that were not found in the peripheral blood of controls. These TCRs encoded a range of V, J, and complementarity determining region 3 (CDR3) sequences on the alpha-chain, and displayed restricted V-beta use. The nucleotides encoding these shared TCR CDR3s varied, suggesting immune selection of this response. Harnessing these T cells may provide practical strategies to improve the shared antigen-specific response to breast cancer.T-cell receptors | breast cancer | emulsion RT-PCR | high-throughput sequencing | T-cell repertoire profiling I nfiltration of numerous tumors by CD8 + alpha-beta T cells is associated with better outcomes and longer survival times for patients with breast cancer (1-5). Targeted immune-based therapies hold great promise toward improving breast cancer treatments (6, 7). Studies have examined the immune phenotype of breast cancer tumor-infiltrating lymphocytes (TILs), suggesting that activated nonsuppressive T cells are of most benefit (8). Further assessment of the TIL repertoire has broad implications for breast cancer therapies in antigen discovery, cancer vaccines, and adoptive cell therapies (7).Unique genetic recombination events are required to produce the T-cell receptor (TCR) (reviewed in 9). The alpha-and beta-chains of the TCR undergo V(D)J recombination and heterodimerize in the thymus, resulting in a diverse T-cell repertoire that specifically recognizes peptide-MHC complexes. Many studies have analyzed the alpha-and beta-chains of TIL TCRs separately using highthroughput sequencing to describe the diversity of TILs (10-13). Pairs are readily identified after expansion of T-cell clones, although culture of T cells can lead to substantial skewing of the repertoire (14), which may select for T cells of varied affinity or avidity (15). Single-cell sequencing identifies alpha-beta pairs, but is often laborious and has rela...
Background: Vaccination with mimotopes, peptide mimics of epitopes, stimulates a range of T cell protection.Results: Mimotopes identified from peptide libraries by T cells with common receptors increased immunity more than those with rare high affinity receptors.Conclusion: T cell prevalence must be considered when designing peptide vaccines.Significance: Optimizing mimotopes will improve antigen-specific vaccines for applications including cancer immunotherapies.
Forty-five channel catfish, Ictalurus punctatus (Rafinesque), fingerlings were inoculated with Edwardsiella ictaluri to determine the usefulness of monoclonal antibodies for indirect fluorescent antibody techniques for confirming clinical diagnosis of enteric septicaemia of catfish. Bacteriological and indirect fluorescent antibody results were compared statistically and found to correlate in 90 3% of the cases. A method for incorporating monoclonals for indirect fluorescent antibody into the speciation of Edwardsiella ictaluri and the use of monoclonal antibodies in diagnosis is described.
Sarcoidosis is a granulomatous disease that primarily affects the lungs and is characterized by an accumulation of CD4+ T cells in the bronchoalveolar lavage (BAL). Previous work has indicated that HLA-DRB1*03:01+ (DR3+) patients diagnosed with the acute form of the disease, Löfgren’s syndrome (LS), have an accumulation of CD4+ T cells bearing TCRs utilizing TRAV12-1 (formerly AV2S3). However, the importance of these α-chains in disease pathogenesis and the paired TCRβ chain remains unknown. This study aimed to identify expanded αβTCR pairs expressed on CD4+ T cells derived from the BAL of DR3+ LS patients. Using a deep-sequencing approach, we determined the TCRα and TCRβ chain usage as well as αβTCR pairs expressed on BAL CD4+ T cells from LS patients. TRAV12-1 and TRBV2 (formerly BV22) were the most expanded V region gene segments in DR3+ LS patients relative to control subjects, and TRAV12-1 and TRBV2 CDR3 motifs were shared between multiple DR3+ LS patients. When assessing αβTCR pairing, TRAV12-1 preferentially paired with TRBV2, and these TRAV12-1/TRBV2 TCRs displayed CDR3 homology. These findings suggest that public CD4+ T cell receptor repertoires exist amongst Löfgren’s syndrome patients and that these T cells are recognizing the putative sarcoidosis-associated antigen(s) in the context of HLA-DR3.
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