Genetic aspects of immunoglobulins and cyclophilin A in milk as potential indicators of mastitis resistance in Holstein cows.

Mastitis is one of the most frequent and costly diseases affecting dairy cattle. Natural antibodies (immunoglobulins) and cyclophilin A (CyPA), the most abundant member of the family of peptidyl prolyl cis/trans isomerases, in milk may serve as indicators of mastitis resistance in dairy cattle. However, genetic information for CyPA is not available, and knowledge on the genetic and nongenetic relationships between these immune-related traits and somatic cell score (SCS) and milk yield in dairy cattle is sparse. Therefore, we aimed to comprehensively evaluate whether immune-related traits consisting of 5 Ig classes (IgG, IgG1, IgG2, IgA, and IgM) and CyPA in the test-day milk of Holstein cows can be used as genetic indicators of mastitis resistance by evaluating the genetic and nongenetic relationships with SCS in milk. The nongenetic factors affecting immune-related traits and the effects of these traits on SCS were evaluated. Furthermore, the genetic parameters of immune-related traits according to health status and genetic relationships under different SCS environments were estimated. All immune-related traits were significantly associated with SCS and directly proportional. Additionally, evaluation using a classification tree revealed that IgA, IgG2, and IgG were associated with SCS levels. Genetic factor analyses indicated that heritability estimates were low for CyPA (0.08) but moderate for IgG (0.37), IgA (0.44), and IgM (0.44), with positive genetic correlations among Ig (0.25-0.96). We also evaluated the differences in milk yield and SCS of cows between the low and high groups according to their sires' estimated breeding value for immune-related traits. In the high group, IgA had a significantly lower SCS in milk at 7 to 30 d compared with that in the low group. Furthermore, the Ig in milk had high positive genetic correlations between healthy and infected conditions (0.82-0.99), suggesting that Ig in milk under healthy conditions could interact with those under infected conditions, owing to the genetic ability based on the level of Ig in milk. Thus, Ig in milk are potential indicators for the genetic selection of mastitis resistance. However, because only the relationship between immune-related traits and SCS was investigated in this study, further study on the relationship between clinical mastitis and Ig in milk is needed before Ig can be used as an indicator of mastitis resistance.

Prevention of mastitis in multiparous dairy cows with a previous history of mastitis by oral feeding with probiotic Bacillus subtilis.

Mastitis is a very common inflammatory disease of the mammary gland of dairy cows, resulting in a reduction of milk production and quality. Probiotics may serve as an alternative to antibiotics to prevent mastitis, and the use of probiotics in this way may lessen the risk of antibiotic resistant bacteria developing. We investigated the effect of oral feeding of probiotic Bacillus subtilis (BS) C-3102 strain on the onset of mastitis in dairy cows with a previous history of mastitis. BS feeding significantly decreased the incidence of mastitis, the average number of medication days and the average number of days when milk was discarded, and maintained the mean SCC in milk at a level substantially lower than the control group. BS feeding was associated with lower levels of cortisol and TBARS and increased the proportion of CD4+ T cells and CD11c+ CD172ahigh dendritic cells in the blood by flow cytometry analysis. Parturition increased the migrating frequency of granulocytes toward a milk chemoattractant cyclophilin A in the control cows, however, this was reduced by BS feeding, possibly indicating a decreased sensitivity of peripheral granulocytes to cyclophilin A. These results reveal that B. subtilis C-3102 has potential as a probiotic and has preventative capacity against mastitis in dairy cows.

Phenotypic and functional analysis of bovine peripheral blood dendritic cells before parturition by a novel purification method.

Dendritic cells (DCs) are specialized antigen presenting cells specializing in antigen uptake and processing, and play an important role in the innate and adaptive immune response. A subset of bovine peripheral blood DCs was identified as CD172a+ /CD11c+ /MHC (major histocompatibility complex) class II+ cells. Although DCs are identified at 0.1%-0.7% of peripheral blood mononuclear cells (PBMC), the phenotype and function of DCs remain poorly understood with regard to maintaining tolerance during the pregnancy. All cattle used in this study were 1 month before parturition. We have established a novel method for the purification of DCs from PBMC using magnetic-activated cell sorting, and purified the CD172a+ /CD11c+ DCs, with high expression of MHC class II and CD40, at 84.8% purity. There were individual differences in the expressions of CD205 and co-stimulatory molecules CD80 and CD86 on DCs. There were positive correlations between expression of cytokine and co-stimulatory molecules in DCs, and the DCs maintained their immune tolerance, evidenced by their low expressions of the co-stimulatory molecules and cytokine production. These results suggest that before parturition a half of DCs may be immature and tend to maintain tolerance based on the low cytokine production, and the other DCs with high co-stimulatory molecules may already have the ability of modulating the T-cell linage.

[Cerebral artery lesion in a patient with infective endocarditis: serial MRI and MRA findings of cerebral artery stenosis].

We reported a case of infective endocarditis (IE) complicated with bacterial meningitis and cerebral artery stenosis. A 22-year-old man was admitted to our hospital because of IE. Although benzylpenicillin administration was continued, he abruptly developed consciousness disturbance on the seventh day. His cerebrospinal fluid indicated bacterial meningitis. MRI with gadolinium (Gd) enhancement showed septic embolism in the left parietal lobe and bi-linear enhancement on the right middle cerebral artery (MCA). MRA demonstrated narrowing of the MCA at the same site as the bi-linear Gd enhancement. We considered that these findings show narrowing of the MCA was due to cerebral arteritis. Intravenous administration of ampicillin and cefpirome gradually improved both IE and cerebral artery stenosis. We wish to emphasize that combination of MRI with Gd enhancement and MRA may be useful not only for diagnosis of cerebral artery stenosis but also for evaluation of treatment effect.

[Two cases of myelitis associated with Sjögren syndrome without xerosis: characteristic MRI findings].

We report two cases of myelitis associated with Sjögren syndrome without xerosis. Case 1: A 30-year old woman developed dysesthesia on both upper extremities and weakness of the right arm. A T2-weighted MRI examination showed a high-intensity signal and a swollen lesion between the first and seventh cervical vertebral levels. She was diagnosed as having primary Sjögren syndrome based on the positive finding of a Saxon test, typical salivary gland scintigraphy findings, and an elevated anti-SS-A antibody titer. We suspected that her myelitis was associated with Sjögren syndrome and treated her using steroid therapy. Although her symptoms were alleviated, her myelitis relapsed at the same location after the cessation of steroid therapy. Case 2: A 31-year-old woman developed dysesthesia on her neck and both upper extremities and exhibited tonic spasm. A T2-weighted MRI examination showed a high-intensity signal and a swollen lesion between the first and sixth cervical vertebral levels. She was diagnosed as having primary Sjögren syndrome based on the positive findings of a Rose Bengal test, a Schirmer's test, and a Saxon test as well as typical salivary gland scintigraphy findings and elevated titers of anti-SS-A and anti-SS-B antibodies. We suspected that her myelitis was associated with Sjögren syndrome and treated her using steroid therapy. Her symptoms improved after steroid therapy. Based on these two cases, we concluded that MRI findings for myelitis associated with Sjögren syndrome are characterized by a swollen lesion of more than three vertebral segments in length, and the relapse tends to occur at the same location.