Which of the following monoclonal antibodies is a humanized antibody?
**Core Concept**
Humanized antibodies are a type of monoclonal antibody that has been modified to reduce the risk of immune responses against the antibody. They are produced by replacing most of the non-human parts of a murine antibody with human sequences. This process involves grafting the complementarity-determining regions (CDRs) of the murine antibody onto a human antibody framework.
**Why the Correct Answer is Right**
The correct answer is a humanized antibody, meaning that it has been engineered to minimize the risk of an immune response against the antibody. Humanized antibodies are created by replacing most of the non-human parts of a murine antibody with human sequences, which helps to reduce the risk of immune responses and increases the antibody's half-life in the human body.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify whether the antibody is humanized or not. Without more information, it is impossible to determine whether this antibody is humanized or not.
* **Option B:** This option is incorrect because it refers to a chimeric antibody, not a humanized antibody. Chimeric antibodies are created by combining murine and human sequences, but they are not as humanized as humanized antibodies.
* **Option D:** This option is incorrect because it refers to a murine antibody, not a humanized antibody. Murine antibodies are derived from mice and are not humanized.
**Clinical Pearl / High-Yield Fact**
Humanized antibodies are often used to treat autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis, where the immune system is overactive and attacks the body's own tissues. By reducing the risk of immune responses against the antibody, humanized antibodies can provide long-term treatment and improve patient outcomes.
**Correct Answer:** C.