Protein identified that turns off HIV-fighting T cells

November 10, 2008

In HIV-infected patients the body's immune system is unable to fight off the virus. A new study to be published online on November 10th in the Journal of Experimental Medicine shows that T cells in HIV-infected individuals express a protein called TIM-3, which inactivates their virus killing capacity. Blocking this protein, the study suggests, might one day help patients to eliminate HIV as well as other chronic infections.

Large numbers of virus-fighting T cells can be found in the blood of most chronically infected HIV patients. However these cells eventually become exhausted and cannot function. To identify the cause of this exhaustion, a team of researchers at the University of Toronto, lead by Mario Ostrowski, compared blood from healthy individuals and HIV patients. In the patients, TIM-3 was found on a large number of HIV-specific T cells, and the number of TIM-3-positive cells increased with the severity of infection.

Under normal circumstances, exposing T cells to bits of virus causes the cells to replicate and produce virus-killing chemicals. Cells expressing TIM-3, however, were unreactive and TIM-3 was to blame; disrupting its signals restored the cells' virus-fighting functions. TIM-3 normally gets expressed on T cells after they carry out their normal function, perhaps as a way to turn the cells off and thus prevent excessive inflammation. But during HIV infection, persistent TIM-3 expression may help the virus avoid T cell attack.

Whether HIV infection itself induces or sustains TIM-3 is not known. Still, blocking the protein might be a useful way to control virus that persists despite antiretroviral therapy.

Rockefeller University Press

---

---

	The San Francisco General Hospital Handbook of HIV Management: A Guide to the Practical Management of HIV-Infected Patients by P.A. Volberding (Author), Judith A. Aberg (Author) This is the long-awaited HIV-management handbook from Drs. Paul Volberding and Judith Aberg and their AIDS experts colleagues from the world-famed AIDS Division of the San Francisco General hospital. In the words of Dr. Volberding, this handbook offers concise, practical help in diagnosing and treating the major complications of HIV disease. Designed for both hospital and outpatient settings, the book gets to the heart of the matter with algorithms, drug doses and complications. It reviews the management of specific populations and includes the most rapidly growing part of the epidemic, HIV in women. Although there are several excellent and comprehensive HIV textbooks, this genuinely practical handbook should be of value to all HIV clinicians as a daily reference." Six chapters cover the...
	HIV/Aids Community Information Services: Experiences in Serving Both At-Risk and HIV-Infected Populations (Haworth Medical Information Sources) by M Sandra Wood (Author), Jeffrey T Huber (Author) Information forms the basis for education, and currently education is the only weapon available to stem the spread of HIV/AIDS and to foster empathy toward individuals already affected by the disease. HIV/AIDS and Community Information Services provides readers with insight into the information construct within the AIDS arena and how that construct affects the provision of information services to the HIV/AIDS affected population. It will serve as an irreplaceable reference as the number of individuals with AIDS increases, creating a greater demand for information and making that information increasingly difficult to provide. While directories exist to assist with practical approaches to accessing HIV/AIDS-related information, none had served as a comprehensive resource concerning...
	An Assessment of Services Provided to Children Affected and Infected by HIV/AIDS in Windhoek, Namibia (Sparrow Readers 4) by Cynthy Haihambo (Author) This study is supported by the World Forum Foundation, the University of Namibia and the Centre for Social Justice and Social Change of the University of Western Sydney. It represents a first step to corroborate research into HIV/AIDS with current knowledge about the outcome of experiences during early life, in the Namibian context. Using quantitative and qualitative data, the study provides an insight into what it means to be young, orphaned, infected or affected in other ways by HIV/AIDS.
	Treatment for HIV-infected alcohol and other drug abusers (SuDoc HE 20.418:15) by Peter A. Selwyn (Author)
	HIV-infected: Webster's Timeline History, 1987 - 2007 by Icon Group International (Author) Webster's bibliographic and event-based timelines are comprehensive in scope, covering virtually all topics, geographic locations and people. They do so from a linguistic point of view, and in the case of this book, the focus is on "HIV-infected," including when used in literature (e.g. all authors that might have HIV-infected in their name). As such, this book represents the largest compilation of timeline events associated with HIV-infected when it is used in proper noun form. Webster's timelines cover bibliographic citations, patented inventions, as well as non-conventional and alternative meanings which capture ambiguities in usage. These furthermore cover all parts of speech (possessive, institutional usage, geographic usage) and contexts, including pop culture, the arts, social...
	My life, a life story of a man infected: A Man's Life before and after HIV (Volume 1) by Mr David H Donahue (Author), David H Donahue (Author) This book is a detailed look at the life of a former Marine and electrician who grew up in an environment of abuse, alcoholism and suicide. It follows the author from a childhood of abuse to his fathers suicide and a life of struggle. From a successful stint in the U.S. Marine Corps to homelessness and success as an electrician and a final fall when diagnosed with full blown AIDS. This is a story of a man who through all of complications continued to have hope. Inspirational and heartbreaking.
	Serving Children HIV Infected Children in Day Care by Donna Pressma (Author), L. Jean Emery (Author)
	Nursing Care of the HIV-Infected Patient (Clinical Nursing Series) by Lori A DeLorenzo (Author), Connie Ingram (Author) From Wikipedia: Human immunodeficiency virus (HIV) is a lentivirus (a member of the retrovirus family) that causes acquired immunodeficiency syndrome (AIDS),[1][2] a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk. Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. The four major routes of transmission are unsafe sex, contaminated needles, breast milk, and transmission from an infected mother to her baby at birth (perinatal transmission). Screening of blood products for HIV has largely eliminated transmission through blood...
	Johns Hopkins HIV Guide 2012 by Joel E. Gallant (Author) Based On The Same Award-Winning Content As The Johns Hopkins POC-IT Center Online Database, The Johns Hopkins HIV Guide 2012 Is The Most Up-To-Date HIV Treatment And Management Resource On The Market. Written By Dr. Joel E. Gallant, World Renowned Expert In The Field Of HIV And Infectious Disease, This Concise And Well-Organized Medical Reference Is Broken Down Into Several Modules, Including: Diagnosis And Evaluation, Treatment Options, Resistance And Complications, Prophylaxis And Antiretroviral Drug Summaries. Johns Hopkins HIV Guide 2012 Contains The Most Current, Relevant And Evidence-Based Information On HIV And AIDS. Selected Topics Include: • Antiretroviral Therapy Adverse Effects • HIV Antibody Testing • Important Genotype-Resistant Patterns • Musculoskeletal And...