Dr. Ralph M. Steinman was awarded Nobel Prize for his discovery on:
role of dendritic cells in adaptive immunity
Ralph M. Steinman's Nobel Prize Discovery
Dr. Ralph M. Steinman was a pioneering immunologist whose work significantly advanced our understanding of the immune system. He was awarded the Nobel Prize in Physiology or Medicine in 2011 for his groundbreaking discoveries.
The question asks about the specific discovery for which he received this prestigious award. Let's look at the options provided:
- acquired immunological tolerance: This relates to how the immune system learns not to react to certain substances. While important in immunology, it's not Steinman's Nobel-winning discovery.
- role of major histocompatibility complex in antigen recognition by T-cells: The MHC's role in presenting antigens to T-cells is a fundamental concept, but the primary discovery related to this was by others, leading to a Nobel Prize in 1980.
- chemical structure of antibody: The detailed chemical structure of antibodies was determined by separate research efforts, also recognized with a Nobel Prize in 1972.
- role of dendritic cells in adaptive immunity: This option directly relates to Dr. Steinman's most famous discovery.
Dendritic Cells and Adaptive Immunity
In 1973, Ralph Steinman and his colleague Zanvil Cohn discovered a new type of cell in the immune system which they named "dendritic cells" because of their branched shape resembling dendrites of nerve cells. Initially, their function was unclear.
Through subsequent research, Steinman demonstrated that these dendritic cells are crucial in initiating and regulating the adaptive immune response. They act as professional antigen-presenting cells (APCs).
Here's why their role is vital:
- Dendritic cells reside in tissues exposed to the external environment (like skin, mucous membranes).
- They capture antigens (foreign substances like parts of bacteria or viruses).
- Upon capturing antigens, they migrate to lymph nodes.
- In the lymph nodes, they present these captured antigens to T-cells, particularly naive T-cells.
- This presentation process is critical for activating T-cells, which then coordinate the adaptive immune response to specifically target the invading pathogen.
- Without effective antigen presentation by dendritic cells, the adaptive immune system struggles to mount a proper defense.
Dr. Steinman's work revealed that dendritic cells are the primary initiators of the adaptive immune response, linking the innate (first line of defense) and adaptive (highly specific) parts of the immune system. This discovery revolutionized the understanding of how adaptive immunity is controlled and has had significant implications for the development of vaccines and immunotherapies.
Therefore, Dr. Ralph M. Steinman was awarded the Nobel Prize in Physiology or Medicine in 2011 specifically for his discovery of the dendritic cell and its role in adaptive immunity.
Important Questions from Immune System
Bacterial infections are generally divided into two broad classes: intracellular and extracellular bacterial infections. Given below are some of the properties which are applicable for bacterial infections.
A. Humoral immune response is the main protective response against extracellular bacteria.
B. Innate immunity is not effective against intracellular bacterial pathogens.
C. Bacterial endotoxins do not induce an innate immune response.
D. Intracellular bacterial infections generally induce a cell-mediated immune response resulting in secretion of cytokines which activate macrophages.
Which one of the following combination of statements is correct?
The immunoglobulin heavy-chain that is rearranged first and is displayed on the surface of early stages of B-cell development is associated with:
Which one of the following systems forms a chemical mediator that is involved in the mechanism of pain during inflammation?
Suresh was bitten by a poisonous snake and was immediately treated with anti-venom human immunoglobulin and was saved. A year later he was bitten by the same type of snake second time. Predict his response to the venom from second bite from the following:
An antigen was injected into a mouse. Macrophages and antigen primed TH cells were isolated from this mouse to perform the following in vitro experiments:
A. Macrophages were treated with the antigen for an hour and then incubated with TH cells.
B. Macrophages were treated with paraformaldehyde first and then treated with the antigen for an hour. These macrophages were then incubated with T H cells.
C. Macrophages were treated with paraformaldehyde first then treated with the digested (proteolytically cleaved) antigen for an hour. These macrophages were then incubated with T H cells.
D. Macrophages were treated with the antigen for an hour and then treated with paraformaldehyde. These macrophages were then incubated with TH cells.
Which of the above experiments would lead to TH cells proliferation?
