Progress 10/01/03 to 09/30/06
Outputs
The objective of this study was to examine the effect of maternal immunization against myostatin, a negative regulator of skeletal muscle growth, in broiler hens on post-hatch broiler growth and skeletal muscle mass. Twelve 5 month-old Cobb broiler hens were divided into four groups: CON, rMYO, MYO1 and MYO2. The CON group was immunized with 1 mg of keyhole lymphet hemocyanin (KLH), rMyo with 1 mg of recombinant active form of myostatin, MYO1 with 1 mg of 24-mer myostatin peptide-KLH conjugate, and MYO2 with 1 mg of 15-mer myostatin peptide-KLH conjugate. Hens in each group were housed together with one 5 month-old Cobb rooster, and the roosters in each group were rotated weekly. Antibody titers were detected in hens' sera, yolk IgY and post-hatch chicks'sera of the rMYO, MYO1 and MYO2 groups, indicating a transfer of antibodies into fertilized eggs and post-hatch chick's circulation. Post-hatch broilers from the rMYO and MYO2 groups showed significantly enhanced
growth as compared to the CON group, resulting in 7.6% (rMYO) and 9.1% (MYO2) increase in body weight at 28 d after hatch. Similar to the body weight response, the carcass weight of the MYO2 was significantly heavier than that of the CON. The weights of breast muscle and thigh-leg of the rMYO and MYO2 groups were significantly heavier than those of the Con group. The percentages of breast muscle mass to body mass of the rMYO and MYO2 groups were significantly higher than that of the CON group, indicating that the growth-enhancing response was more selective in skeletal muscles than in other tissues of the body. In contrast, the growth of the MYO1 group was not significantly different from that of the CON group. No significant difference was also observed between the CON and MYO1 in carcass and muscle weight. The results of this study indicate that maternal immunization against myostatin is a potential means to improve skeletal muscle growth of broilers.
Impacts
Myostatin has shown to be the most potent negative regulator of skeletal muscle growth. Therefore, we examined whether immuno-neutralization of myostatin is an effective approach to increase skeletal muscle growth via suppression of myostatin's biological activity. Our results demonstrate that in-ovo administration of anti-myostatin antibody into the yolk enhances the growth of body and skeletal muscle in broiler. Furthermore, immunization of hen against myostatin improved posthatch growth of skeletal muscles. These results indicate that immuno-neutalization of myostatin is a potentail means to improve skeletal muscle growth.
Publications
- (Peer Reviewed Paper) Y.S. Kim, N.K. Bobilli, K.S. Paek and H.J. Jin. 2006. In-ovo administration of monoclonal anti-myostatin antibody improve post-hatch chicken growth and muscle mass. Poultry Science 85:1062-1071.
- (Published Abstract) N.K. Bobbili, Y.K. Lee and Y.S. Kim. 2006. Production of a polyclonal antibody against unprocessed chicken myostatin and the effects of in-ovo administration of the antibody on post-hatch broiler growth and muscle mass. J. Anim. Sci. 84(suppl. 1):30
|
Progress 10/01/04 to 09/30/05
Outputs
The objective of this study was to produce a monoclonal anti-myostatin antibody and to examine the effects of in-ovo administration of the antibody on post-hatch broiler growth and muscle mass. Mature form of myostatin was expressed in E. coli and used as an immunogen in producing monoclonal antibody against myostatin. One hybridoma clone (mAb-c134) that showed the strongest affinity to the immunogen in Western blot analysis was used in producing a large quantity of monoclonal anti-myostatin antibody. In Western blot analysis, the mAb-c134 showed a strong binding affinity to a commercially available mature myostatin. Competitive ELISA demonstrated a binding ability of the mAb-c134 to the native form of mature myostatin in solution. The mAb-c134 demonstrated certain level of cross-reactivity with recombinant human BMP2, but not with recombinant human TGF-beta3 and porcine TGF-beta1. To examine the effects of in-ovo administration of the mAb-c134, eggs were injected
once with 40 micro g mAb-c134 in 50 micro liter PBS per embryo into the albumin or yolk on 3d after incubation. After hatching, chicks were raised for 35d. Broilers injected with the mAb-c134 into the yolk had significantly heavier body (4.2 percent) and muscle (5.5 percent) mass than the control birds in both male and female. No significant difference in body and muscle mass was observed between the control and broilers injected with mAb-c134 into the albumin. The results of this study indicate that immunoneutralization of myostatin during embryonic development is a potential means to improve growth potential of broiler.
Impacts
Myostatin has shown to be the most potent negative regulator of skeletal muscle growth. Therefore, we designed an experiment to examine whether immno-neutralization of myostatin via in-ovo administration of anti-myostatin antibody would modulate post-hatching broiler growth. Our results demonstrate that in-ovo administration of anti-myostatin antibody into the yolk enhances the growth of body and skeletal muscle in broiler, suggesting that suppressing the biological activity of myostatin during embryonic development or early period after hatch would be a potential means to improve skeletal muscle growth of broilers.
Publications
- Kim, Y.S. and Jin, H.J. 2005. Effects of in-ovo administration of monoclonal anti-myostatin antibody on post-hatch chicken growth and muscle mass. J. Anim. Sci. 83(suppl. 1):26.
|
Progress 10/01/03 to 09/30/04
Outputs
Myostatin, a member of the TGF-beta superfamily proteins, inhibits the growth of skeletal muscles. In this study, we examined whether maternal transfer of anti-myostatin antibodies to the embryo affects skeletal muscle growth of the offspring. Twenty BALB/c female mice were divided into four groups: CON, IMM1, IMM2 and IMM3. The CON was immunized with adjuvant, IMM1 with 0.1 mg of myostatin peptide 1 and KLH conjugate, IMM2 with 0.1 mg of myostatin peptide 2 and KLH conjugate and IMM3 with 0.1 mg of the mixture of those two antigens. Peptide 1 and peptide 2 comprised amino acid sequence 79-103 and 50-64 of mature myostatin, respectively. The first immunization was administered at 6 wks of age, and two more booster immunizations were administered 3 wks apart after the first immunization. At 3 wks after the last immunization, the female mice were bred by pairing with male. Pups were weaned at wk 3, then sexed and raised separately for another 5 wks while monitoring body
wt. At 8 wks of age, pups were sacrificed, and weights of carcass, gastrocnemius, plantaris and soleus muscle, epididymal and parametrial fat, and brown adipose fat were measured. Anti-myostatin antibody titers were detected in maternal sera of IMM1, IMM2 and IMM3 during immunization. However, no significant differences in body wt, carcass wt, muscle wt, and fat were observed among the groups.
Impacts
Myostatin has shown to be the single most important molecule that negatively regulates skeletal muscle growth. Our hypothesis, therefore, was that suppressing myostatin activity would improve skeletal muscle growth and subsequent meat production efficiency. In support of the hypothesis, studies recently demonstrated that muscle mass can be significantly increased by the administration of neutralizing anti-myostatin antibodies to adult mice. However, injecting large quantity of antibodies to animals is not feasible for commercial application of the above findings. To circumvent the problem, we devised an approach of immunizing reproducing females against myostatin with an anticipation that the anti-myostatin antibodies delivered to the developing fetus through placental transfer would suppress the biological activity of myostatin, thus resulting in increased skeletal muscle development. The current preliminary results show that maternal immunization against myostatin
did not alter the growth potential of offspring. This suggests that we need more understanding on the process of autoimmune response for the active immunization against myostatin to suppress the biological activity of myostatin, resulting in improved skeletal muscle growth.
Publications
- Jin, H.J., Dunn, M.A., Borthakur, D. and Kim, Y.S. 2004. Refolding and purification of unprocessed porcine myostatin expressed in Escherichia coli. Protein Expression and Purification. 35:1-10.
|
Progress 10/01/02 to 09/30/03
Outputs
No progress to report. This project was initiated on October 1, 2003.
Impacts
No impact to report. This project was initiated on October 1, 2003.
Publications
- No publications reported this period
|
|