Symposium review: Novel strategies to genetically improve mastitis resistance in dairy cattle

Mastitis is a disease of major economic importance to the dairy cattle sector because of the high incidence of clinical mastitis and prevalence of subclinical mastitis and, consequently, the costs associated with treatment, production losses, and reduced animal welfare. Disease-recording systems compiling data from a large number of farms are still not widely implemented around the world; thus, selection for mastitis resistance is often based on genetically correlated indicator traits such as somatic cell count (SCC), udder depth, and fore udder attachment. However, in the past years, several countries have initiated collection systems of clinical mastitis, based on producers recording data in most cases. The large data sets generated have enabled researchers to assess incidence of this disease and to investigate the genetic background of clinical mastitis itself, as well as its relationships with other traits of interest to the dairy industry. The genetic correlations between clinical mastitis and its previous proxies were estimated more accurately and confirmed the strong relationship of clinical mastitis with SCC and udder depth. New traits deriving from SCC were also studied, with the most relevant findings being associated with mean somatic cell score (SCS) in early lactation, standard deviation of SCS, and excessive test-day SCC pattern. Genetic correlations between clinical mastitis and other economically important traits indicated that selection for mastitis resistance would also improve resistance against other diseases and enhance both fertility and longevity. However, milk yield remains negatively correlated with clinical mastitis, emphasizing the importance of including health traits in the breeding objectives to achieve genetic progress for all important traits. These studies enabled the establishment of new genetic and genomic evaluation models, which are more efficient for selection to mastitis resistance. Further studies that are potential keys for future improvement of mastitis resistance are deep investigation of the bacteriology of mastitis, identification of novel indicator traits and tools for selection, and development of a larger female reference population to improve reliability of genomic evaluations. These cutting-edge studies will result in a better understanding of the genetic background of mastitis resistance and enable a more accurate phenotyping and genetic selection to improve mastitis resistance, and consequently, animal welfare and industry profitability.

Hepatitis C Virus Infection and Post-Transplant Diabetes Mellitus among Renal Transplant Patients: A Meta-Analysis

Objective

To examine the association between HCV infection and the occurrence of post-transplant diabetes mellitus (PTDM) among renal transplant patients.

Design

Meta-analysis of observational studies.

Data Sources

We retrieved studies published in any language by systematically searching Medline, and Embase and by manually examining the references of the original articles, reviews, and monographs retrieved.

Review Methods

We included cohort and case-control studies reporting relative risk estimates and 95% confidence intervals (CIs) for PTDM occurrence with HCV after renal transplantation. Thirteen studies providing information on a total of 30,099 unique patients were included in our meta-analysis.

Results

Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random-effects pooled estimates. The pooled relative risk (RR) for PTDM after RT was 2.73 with a 95% confidence interval (CI) of 1.94; 3.83 (10 studies). In a stratified analysis including only large studies (2 studies), the pooled RR was 1.36 (95% CI, 1.21; 1.54). Egger's regression test showed some evidence of publication bias (p=0.0001), but our sensitivity analysis showed that this issue did not meaningfully change the results.

Conclusions

Our study shows a marked increase of the risk of post-transplant diabetes mellitus in anti-hepatitis C virus-positive renal transplant recipients. The excess risk of death in hepatitis C virus-positive renal transplant recipients may be at least partially attributed to post-transplant diabetes mellitus with its attendant complications.

Genetic parameters for αS1-casein and αS2-casein phosphorylation isoforms in Dutch Holstein Friesian

Relative concentrations of α_S1-casein and α_S2-casein (α_S1-CN and α_S2-CN) phosphorylation isoforms vary considerably among milk of individual cows. We estimated heritabilities for α_S2-CN phosphorylation isoforms, determined by capillary zone electrophoresis from 1,857 morning milk samples, and genetic correlations among α_S2-CN phosphorylation isoforms in Dutch Holstein Friesian. To investigate if phosphorylation of α_S1-CN and α_S2-CN are due to the same genetic mechanism, we also estimated genetic correlations between α_S1-CN and α_S2-CN phosphorylation isoforms as well as the genetic correlations between the phosphorylation degrees (PD) of α_S1-CN and α_S2-CN defined as the proportion of isoforms with higher degrees of phosphorylation in total α_S1-CN and α_S2-CN, respectively. The intra-herd heritabilities for the relative concentrations of α_S2-CN phosphorylation isoforms were high and ranged from 0.54 for α_S2-CN-10P to 0.89 for α_S2-CN-12P. Furthermore, the high intra-herd heritabilities of α_S1-CN PD and α_S2-CN PD imply a strong genetic control of the phosphorylation process, which is independent of casein production. The genetic correlations between α_S2-CN phosphorylation isoforms are positive and moderate to high (0.33-0.90). Furthermore, the strong positive genetic correlation (0.94) between α_S1-CN PD and α_S2-CN PD suggests that the phosphorylation processes of α_S1-CN and α_S2-CN are related. This study shows the possibility of breeding for specific α_S1-CN and α_S2-CN phosphorylation isoforms, and relations between the phosphorylation degrees of α_S1-CN and α_S2-CN and technological properties of milk need to be further investigated to identify potential benefits for the dairy industry.

A phase II trial of lenalidomide plus rituximab in previously untreated follicular non-Hodgkin's lymphoma (NHL): CALGB 50803 (Alliance)

BACKGROUND

This multicenter, phase II trial tested the tolerability and efficacy of lenalidomide plus rituximab in patients with previously untreated follicular lymphoma (FL).

PATIENTS AND METHODS

Patients with grade 1-3a FL, stage 3-4 or bulky stage 2, FL international prognostic index (FLIPI) 0-2, and no prior therapy were eligible to receive rituximab 375 mg/m2 weekly during cycle 1 and day 1 of cycles 4, 6, 8, and 10, plus lenalidomide 20-25 mg on days 1-21 for twelve 28-day cycles. The primary objectives were to evaluate response rates [complete (CR) and overall] and time to progression. Secondary objectives included toxicity, response according to polymorphisms in FcgR2A and FcgR3A, and changes in circulating pro-angiogenic cells.

RESULTS

From October 2010 to September 2011, 66 patients were enrolled. Median age was 53 years, 34 were female, 15 had bulky disease, 21 were FLIPI 0-1, 43 FLIPI 2, and 2 FLIPI 3. One patient withdrew before receiving treatment. Fifty-one patients completed 12 cycles of lenalidomide. Reasons for discontinuation included withdrawal (n = 6), adverse events (n = 6), progression (n = 2). Grade 3-4 hematologic toxicity included neutropenia (21%), lymphopenia (9%), and thrombocytopenia (2%), infection (11%), and rash (8%). Grade 1-2 toxicity included fatigue (78%), diarrhea (37%), rash (32%), and febrile neutropenia in one patient. The overall response rate was 95%; the CR rate was 72% (95% confidence interval, 60% to 83%). With a median follow-up of 5 years, the 2- and 5-year progression-free survival were 86% and 70%, respectively, and the 5-year overall survival was 100%. There was no association between CR rate or PFS and FLIPI, histological grade, bulky disease, FcgR2A/FcgR3A polymorphism, or change in circulating endothelial cell/hematopoietic progenitor cell.

CONCLUSION

Lenalidomide plus rituximab was associated with low rates of grade 3-4 toxicity, yielded a CR rate and PFS similar to chemotherapy-based treatment and may represent a reasonable alternative to immunochemotherapy in previously untreated FL.

CLINICALTRIALS.GOV IDENTIFIER

NCT01145495.

The skin barrier function gene SPINK5 is associated with challenge-proven IgE-mediated food allergy in infants

BACKGROUND

A defective skin barrier is hypothesized to be an important route of sensitization to dietary antigens and may lead to food allergy in some children. Missense mutations in the serine peptidase inhibitor Kazal type 5 (SPINK5) skin barrier gene have previously been associated with allergic conditions.

OBJECTIVE

To determine whether genetic variants in and around SPINK5 are associated with IgE-mediated food allergy.

METHOD

We genotyped 71 "tag" single nucleotide polymorphisms (tag-SNPs) within a region spanning ~263 kb including SPINK5 (~61 kb) in n=722 (n=367 food-allergic, n=199 food-sensitized-tolerant and n=156 non-food-allergic controls) 12-month-old infants (discovery sample) phenotyped for food allergy with the gold standard oral food challenge. Transepidermal water loss (TEWL) measures were collected at 12 months from a subset (n=150) of these individuals. SNPs were tested for association with food allergy using the Cochran-Mantel-Haenszel test adjusting for ancestry strata. Association analyses were replicated in an independent sample group derived from four paediatric cohorts, total n=533 (n=203 food-allergic, n=330 non-food-allergic), mean age 2.5 years, with food allergy defined by either clinical history of reactivity, 95% positive predictive value (PPV) or challenge, corrected for ancestry by principal components.

RESULTS

SPINK5 variant rs9325071 (A⟶G) was associated with challenge-proven food allergy in the discovery sample (P=.001, OR=2.95, CI=1.49-5.83). This association was further supported by replication (P=.007, OR=1.58, CI=1.13-2.20) and by meta-analysis (P=.0004, OR=1.65). Variant rs9325071 is associated with decreased SPINK5 gene expression in the skin in publicly available genotype-tissue expression data, and we generated preliminary evidence for association of this SNP with elevated TEWL also.

CONCLUSIONS

We report, for the first time, association between SPINK5 variant rs9325071 and challenge-proven IgE-mediated food allergy.

Diet-induced modifications to milk composition have long-term effects on offspring growth in rabbits

It has been clearly demonstrated that the maternal nutritional status during pregnancy and lactation has long-term effects on offspring health. In mammals, milk represents the first maternal support provided to the newborns so that its composition may play a major role in long-term programming. We therefore assessed the effects of maternal high-fat/high-sugar obesogenic (OD) or control (CD) diets on offspring growth and adiposity in the rabbit. Between 7 and 20 wk of age, the BW gain of OD milk-fed rabbits was higher than that of CD milk-fed rabbits ( < 0.05). Body fat mass measurements at 21 wk of age revealed a significant increase in body adiposity as a function of milk ingested during the neonatal period, in both female and male offspring ( < 0.05). A marked weight gain difference was observed according to the milk in both female and male offspring. Moreover, we investigated the composition in major proteins and leptin levels in milk from OD or CD diet-fed dams. Liquid chromatography-mass spectrometry analysis of individual CD skimmed milk samples enabled identification and quantification of the rabbit main milk proteins and of their main phosphorylated isoforms at 2 different stages of lactation (3 and 10 d). Here we show that the OD diet induced a reduction in the whey acidic protein content concomitantly with both an increase in serum albumin and lactoferrin contents and in the phosphorylated isoforms of the main milk proteins. Furthermore, a sharp rise in leptin levels was observed in the milk of OD diet-fed dams on Day 10 of lactation when compared with CD diet animals ( < 0.05). Taken together, these findings provide evidence that lactation is a critical window of development during which exposure to a deleterious diet is highly detrimental to long-term outcomes. Moreover, these insights suggest that it may be possible to prevent at least some of the adverse effects of inadequate maternal nutrition on the long-term metabolic outcomes of the offspring through nutritional interventions applied during the lactation period.

The SigmaR1 chaperone drives breast and colorectal cancer cell migration by tuning SK3-dependent Ca2+ homeostasis

The remodeling of calcium homeostasis contributes to the cancer hallmarks and the molecular mechanisms involved in calcium channel regulation in tumors remain to be characterized. Here, we report that SigmaR1, a stress-activated chaperone, is required to increase calcium influx by triggering the coupling between SK3, a Ca2+-activated K+ channel (KCNN3) and the voltage-independent calcium channel Orai1. We show that SigmaR1 physically binds SK3 in BC cells. Inhibition of SigmaR1 activity, either by molecular silencing or by the use of sigma ligand (igmesine), decreased SK3 current and Ca2+ entry in breast cancer (BC) and colorectal cancer (CRC) cells. Interestingly, SigmaR1 inhibition diminished SK3 and/or Orai1 levels in lipid nanodomains isolated from BC cells. Analyses of tissue microarray from CRC patients showed higher SigmaR1 expression levels in cancer samples and a correlation with tumor grade. Moreover, the exploration of a cohort of 4937 BC patients indicated that high expression of SigmaR1 and Orai1 channels was significantly correlated to a lower overall survival. As the SK3/Orai1 tandem drives invasive process in CRC and bone metastasis progression in BC, our results may inaugurate innovative therapeutic approaches targeting SigmaR1 to control the remodeling of Ca2+ homeostasis in epithelial cancers.