Navigation Links
Helper T cell


A helper (or TH) T cell is a T cell (a type of white blood cell) which has on its surface antigen receptors that can bind to fragments of antigens displayed by the Class II MHC molecules found on professional antigen-presenting cells (APCs).

Once bound to an antigen, the TH cell proliferates and differentiates into activated TH cells and memory TH cells.

  • Activated TH cells secrete cytokines, proteins or peptides that stimulate other lymphocytes; the most common is interleukin-2 (IL-2), which is a potent T cell growth factor. Activated, proliferating TH cells can differentiate into two major subtypes of cells, Th1 and Th2 cells. These subtypes are defined on the basis of specific cytokines produced. Th1 cells produce interferon-gamma and interleukin 12, while Th2 cells produce interleukin-4 , interleukin-5 and interleukin-13.
  • Memory TH cells are specific to the antigen they first encountered and can be called upon during the secondary immune response .

Most TH cells have present on the cell surface the protein CD4 , which is attracted to portions of the Class II MHC molecule. This affinity keeps the TH cell and the target cell bound closely together during antigen-specific activation. TH cells with CD4 surface protein are called CD4+ T cells. The decrease in number of CD4+ T cells is the primary mechanism by which HIV causes AIDS.


'"/>


(Date:7/11/2014)... The University of Chicago is creating a new ... at the University,s Institute for Molecular Engineering and ... million donation from the Millicent and Eugene Bell ... will reside within the Institute for Molecular Engineering. ... research project at the MBL,s Eugene Bell Center ...
(Date:7/11/2014)... researchers at the National Institute of Standards and ... their work more effectively, they often prove that ... was the case recently for M. Lorna De ... the growing specialization of glycomics. Glycomics is the ... glycans that are attached to proteins and lipids ...
(Date:7/11/2014)... with other group members to reduce aggression and gain ... strategy for grooming activities shows a certain pattern across ... scientific journal Biology Letters . , Grooming between ... without ulterior motives. To be groomed has hygienic benefits ... another individual can provide access to infants, mating opportunities ...
Breaking Biology News(10 mins):New professorship in tissue engineering links molecular engineering, marine biology 2Baboons groom early in the day to get benefits later 2
... EAST LANSING, Mich. With the help of a ... researcher is expanding a pilot program statewide to help ... low socioeconomic settings increase their physical activity. ... Lorraine Robbins of the College of Nursing and funded ...
... of Dental Medicine to study an isolated agent from common ... beta defensins (HBDs)nature,s way of keeping oral microbes from entering ... to create new treatments to block bacteria from entering through ... Weinberg, professor and chair of the department of biological sciences ...
... Researchers studying hand hygiene of healthcare workers in ... location and type of healthcare worker performing care, resulted ... in the November issue of Infection Control and ... Healthcare Epidemiology of America. "We found that receiving ...
Cached Biology News:$3.6 million nursing research project promotes exercise for girls 2Mother Nature's oral antibiotics research gets $2.25 million help from NIH 2Study reports predictors of poor hand hygiene in an emergency department 2
Other biology definitionOther Tags