Production of viable cloned miniature pigs by aggregation of handmade cloned embryos at the 4-cell stage.

The aim of the present study was to improve the quality of handmade cloned porcine embryos by multiple embryo aggregations. Embryos derived from aggregation of three cloned embryos (3×) had a better blastocyst rate than cloned control (1×) embryos (73.6% vs 35.1%, respectively; P<0.05), but did not differ from those produced by aggregation of two cloned embryos (2×; 63.0%). Total cell numbers differed among treatments (P<0.05), with the greatest cell numbers (126) in the 3× group and the lowest (55) in the control group. The ratio of inner cell mass:total cell number was comparable in the 2× and 3× groups (25.1% vs 26.1%, respectively) and was significantly better than that in the control group (15.3%). The proportion of apoptotic cells in 2× and 3× groups was lower than that in the control group (2.7% and 2.2% vs 4.7%, respectively; P<0.05). Expression of Oct4 and Cdx2 was higher, whereas that of Bax was lower (P<0.05), in the 3× compared with non-aggregate group. Seven piglets were born to two surrogate mothers after embryo transfer of 3× aggregated blastocysts. In conclusion, aggregated embryos had greater total cell numbers and better pluripotency gene expression, with reduced expression of the pro-apoptosis gene Bax. Collectively, these improvement may be associated with the development of cloned embryos to term.

Serum acute phase proteins and swine health status.

The purpose of this study was to investigate the relationship between swine health status and the concentration of the serum acute phase proteins, haptoglobin (HP), and C-reactive protein (CRP). A total of 378 clinically healthy pigs from farms A and B, plus 20 pigs culled from farm A due to poor growth, were used in this experiment. Each pig was examined and blood samples were collected during slaughter. The HP concentration was measured by using an HP-hemoglobin binding assay. The CRP concentration was measured by using a CRP enzyme immunoassay. Gross and histopathological lesions were examined and recorded at slaughter. Representative samples were then collected in order to isolate pathogens. Swine enzootic pneumonia, found in 47.7% of the pigs, was the most common lesion. Other lesions included pleuropneumonia (32.7%), suppurative pneumonia (10.3%), fibrinous pericardititis (4.3%), Ascaris migration in the liver (33.9%), and intestinal serositis (3.0%). On farm A, the percentage of pigs with 1 or more lesions was 88.2%. For culled pigs from farm A, the mean serum concentrations of HP and CRP were 2.23 +/- 0.14 mg/mL and 252.93 +/- 11.62 microg/mL, which were significantly higher than concentrations in clinically normal pigs (1.42 +/- 0.02 mg/mL and 84.88 +/- 2.61 microg/mL, respectively, P < 0.01). Moreover, among clinically normal farm A pigs, the mean HP concentration in pigs with lesions (1.43 +/- 0.02 mg/mL) was significantly higher than in pigs without lesions (1.32 +/- 0.07 mg/mL) (P < 0.05). However, the mean serum CRP concentrations in these animals were not significantly different. On farm B, the percentage of pigs with one or more lesions was 50.0%. Interestingly, the mean serum HP concentration in clinically normal pigs with lesions was significantly lower in farm B pigs (1.23 +/- 0.07 mg/mL) than in the farm A pigs (1.43 +/- 0.02 mg/mL; P < 0.01). However, serum CRP concentrations in farm A and B pigs were not significantly different. Serum HP concentration, which is a better indicator of inflammatory reactions in pig herds than serum CRP concentration, provides an important marker for swine health status.

Protein expression of lymphocytes in HLA-DR transgenic pigs by a proteomic approach.

Matching donor and recipient human leucocyte antigen (HLA-II) could conquer cell-mediated rejection following transplantation. Transgenic pigs carrying HLA genes that "humanize" porcine organs, tissues, and cells were successfully generated. This study further clarifies the effect of HLA-DR transgenes on lymphocyte protein expression, via a proteomic approach. Lymphocytes were isolated from two HLA-DR transgenic pigs and three nontransgenic littermates on 157 d after birth. Soluble protein of 1x10(7) cells was separated using 2-DE. In total, 301 colloidal CBB-stained protein spots detected on all five 2-D gels were quantified. Thirty-three proteins were differentially expressed by a factor of 1.5. These proteins were subsequently identified by MALDI-TOF MS and MALDI-TOF/TOF MS/MS. These proteins were sorted into the following categories: chaperones, T-lymphocyte function, DNA/RNA processing, cytoskeleton-associated proteins, signal transduction, enzymes, and unknown. Previous studies have suggested that some of the identified proteins are associated with lymphocyte activation/proliferation. The identities of the unidentified spots and the systematic effect of these up- and down-regulated proteins on T-cell function in HLA-DR transgenic pigs require further exploration.