User:Emily Jean Onufer
I am a new member of OpenWetWare!
- Emily Jean Onufer
- MIT 20.109
- MIT Address: 479 Commonwealth Ave. Boston, MA 02115
- Home Address: 2756 Ocean Shore Ave. VA Beach, VA 23451
- Hometown: Virginia Beach, VA
Feel free to email me: ejonufer [at] mit.edu
http://mit.edu/Public/ejonufer/Emily%20Jean%20Onufer/ is my resume on my Athena public which gives an overview of my accomplishments as a whole. Basically, I enjoy playing tennis for MIT and being involved in various leadership positions around campus. I love traveling, being outdoors, and learning anything new. I am also adore solving puzzles.
- 2006, Princess Anne High School International Bacc. Graduate
- Present, MIT student, Sophomore
- Infectious Diseases
- Cardiovascular Research
Module 3 Research Project
Did you know that in 2007 alone, 33.2 million people lived with AIDS? Of this number, 2.1 million died, including 330,000 children.
AIDS is now a pandemic, ravaging sub-Saharan Africa and retarding economic growth. Research has been done in a multitude of labs across the country concerning HIV, its deadly retrovirus.
Recent researchers have identified antibodies in the first loop (ECL1) of CCR5 of HIV exposed but uninfected individuals. This means that these antibodies could resist the HIV infection. It would be interesting to analyze and target the specific amino acid residues in this loop to determine which amino acids are involved in antibody binding to CCR5. Studies have been done that showed that amino acid substitutions in positions Alanine-95 and Alanine-96 increased antibody-peptide binding compared to that of the wild-type peptide Aspartate-95 and Phenylalanine-96.
Because of this research and that of others, we would like analyze the binding antibodies for key characteristics that would contribute to their binding affinity. We would then like to target these same residues of Aspartate-95 and Phenylalanine-96 to determine if other types of amino acids would increase the binding affinity. We would use site-directed mutagenesis to test to see how mutating these residues would affect antibody binding to CCR5. If we can determine the residues that bind antibodies most effectively, then we can more easily prevent an HIV-positive patient from becoming infected with AIDS.
- Current Research in the Field and Sources of Information
Source: Pastori, et al. “Two amino acid substitutions within the first external loop of CCR5 induce human immunodeficiency virus-blocking antibodies in mice and chickens.” J Virol. 2008 Apr;82(8):4125-34. Epub 2008 Feb 6.
The CCR5 coreceptor is a seven-transmembrane-spanning receptor involved in chemokine signaling. With regards to our research project, it also is used as a viral coreceptor by HIV, and it presumably mediates the first contacts between HIV and target host cells in mucosal sites, as CCR5-tropic HIV strains are generally the first in pioneering new hosts. Earlier studies have found that antibodies to the first loop (ECL1) of CCR5 have been identified in HIV-exposed uninfected individuals and in HIV-positive nonprogressing subjects. Thus, these antibodies may confer resistance against HIV infection.
To define which amino acids are involved in antibody binding to CCR5, the authors of the journal performed a peptide-scanning assay and studied the immunogenicity of peptides in animal models. A panel of synthetic peptides spanning the CCR5-ECL1 region and displaying glycine or alanine substitutions was assayed for antibody binding with a pool of natural anti-CCR5 antibodies. They used mice and chickens to study the immunogenicity of mutagenized peptide. Structural characterization by NMR spectroscopy and molecular dynamics simulations were performed to better understand the structural and conformational features of the mutagenized peptide. Amino acid substitutions in positions Ala95 and Ala96 increased antibody-peptide binding compared to that of the wild-type peptide (Asp(95)-Phe(96)).
Strikingly, chicken antibodies to the Ala95-96 peptide specifically recognize human CCR5 molecules, downregulate receptors from lymphocytes, inhibit CCR5-dependent chemotaxis, and prevent infection by several R5 viruses, displaying 50% inhibitory concentrations of less than 3 ng/ml. NMR spectroscopy and molecular dynamics simulations proved the high flexibility of isolated epitopes and suggested that A(95)-A(96) substitutions determine a slightly higher tendency to generate helical conformations combined with a lower steric hindrance of the side chains in the peptides. These findings may be relevant to the induction of strong and efficient HIV-blocking antibodies.