Featured Research

from universities, journals, and other organizations

Antibodies that may cut risk of HIV infection better understood

Date:
March 19, 2014
Source:
NIH/National Institute of Allergy and Infectious Diseases
Summary:
What immune response should a vaccine elicit to prevent HIV infection? Two studies bring scientists closer to answering this question by identifying previously unrecognized attributes of antibodies that appear to have reduced the risk of HIV infection in the only clinical trial to show efficacy, albeit modest, of an experimental vaccine regimen in people.

What immune response should a vaccine elicit to prevent HIV infection? Two studies published online today bring scientists closer to answering this question by identifying previously unrecognized attributes of antibodies that appear to have reduced the risk of HIV infection in the only clinical trial to show efficacy, albeit modest, of an experimental vaccine regimen in people.

Earlier analyses of the results of that trial, known as RV144, suggested that antibodies to sites within a part of the HIV envelope called V1V2 correlated with reduced risk of HIV infection. These antibodies belong to a class called immunoglobulin G, or IgG. The new studies by two independent laboratories both found that only one subclass of V1V2-directed IgG antibodies -- the IgG3 subclass -- is associated with antiviral responses linked to the reduced risk of HIV infection seen in RV144. The experiments were led by Georgia D. Tomaras, Ph.D., of the Duke Human Vaccine Institute, and Galit Alter, Ph.D., of the Ragon Institute, with funding in part from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

In the study led by Dr. Tomaras, scientists found that V1V2-specific IgG3 antibodies correlated with a decreased risk of infection in RV144 vaccinees and were linked to HIV-eliminating activity. The researchers also discovered that the level of V1V2-specific IgG3 antibodies in vaccinees' blood waned rapidly, as did the efficacy of the investigational vaccines tested in the RV144 trial (from 60 percent efficacy at 12 months post-vaccination to 31.2 percent efficacy at 42 months). The study led by Dr. Alter demonstrated that RV144 vaccination induced antibodies able to direct multiple, coordinated HIV-eliminating activities, and that these activities were conducted primarily by V1V2-specific IgG3 antibodies.

More research is needed to determine whether V1V2-directed IgG3 antibodies actually protected some vaccinees from HIV infection, as well as whether there was a relationship between the fast decline in IgG3 antibodies and the sharp drop in efficacy of the investigational RV144 vaccines. Information from the current and ongoing studies will help scientists refine their efforts to design and test HIV vaccines that build on the success of RV144.


Story Source:

The above story is based on materials provided by NIH/National Institute of Allergy and Infectious Diseases. Note: Materials may be edited for content and length.


Journal References:

  1. A. W. Chung, M. Ghebremichael, H. Robinson, E. Brown, I. Choi, S. Lane, A.-S. Dugast, M. K. Schoen, M. Rolland, T. J. Suscovich, A. E. Mahan, L. Liao, H. Streeck, C. Andrews, S. Rerks-Ngarm, S. Nitayaphan, M. S. de Souza, J. Kaewkungwal, P. Pitisuttithum, D. Francis, N. L. Michael, J. H. Kim, C. Bailey-Kellogg, M. E. Ackerman, G. Alter. Polyfunctional Fc-Effector Profiles Mediated by IgG Subclass Selection Distinguish RV144 and VAX003 Vaccines. Science Translational Medicine, 2014; 6 (228): 228ra38 DOI: 10.1126/scitranslmed.3007736
  2. N. L. Yates, H.-X. Liao, Y. Fong, A. deCamp, N. A. Vandergrift, W. T. Williams, S. M. Alam, G. Ferrari, Z.-y. Yang, K. E. Seaton, P. W. Berman, M. D. Alpert, D. T. Evans, R. J. O'Connell, D. Francis, F. Sinangil, C. Lee, S. Nitayaphan, S. Rerks-Ngarm, J. Kaewkungwal, P. Pitisuttithum, J. Tartaglia, A. Pinter, S. Zolla-Pazner, P. B. Gilbert, G. J. Nabel, N. L. Michael, J. H. Kim, D. C. Montefiori, B. F. Haynes, G. D. Tomaras. Vaccine-Induced Env V1-V2 IgG3 Correlates with Lower HIV-1 Infection Risk and Declines Soon After Vaccination. Science Translational Medicine, 2014; 6 (228): 228ra39 DOI: 10.1126/scitranslmed.3007730

Cite This Page:

NIH/National Institute of Allergy and Infectious Diseases. "Antibodies that may cut risk of HIV infection better understood." ScienceDaily. ScienceDaily, 19 March 2014. <www.sciencedaily.com/releases/2014/03/140319165208.htm>.
NIH/National Institute of Allergy and Infectious Diseases. (2014, March 19). Antibodies that may cut risk of HIV infection better understood. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2014/03/140319165208.htm
NIH/National Institute of Allergy and Infectious Diseases. "Antibodies that may cut risk of HIV infection better understood." ScienceDaily. www.sciencedaily.com/releases/2014/03/140319165208.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins