Tag: immunity related disorders and problems

Questions Related to immunity related disorders and problems

Graft recognizes the recipient as foreign which can be seen in

  1. Transplantation rejection.

  2. Graft versus host disease.

  3. Passive immunization.

  4. Both A and B.


Correct Option: B
Explanation:
Graft versus host disease is a condition that might occur after an allogeneic transplant. In this, the donated bone marrow or peripheral blood stem cells view the recipient's body as foreign, and thus attack the body. 
So, the correct answer is option B.

Graft versus host disease mostly occurs after 

  1. Xenograft transplant.

  2. Allogenic transplant.

  3. Isograft transplant.

  4. None of the above.


Correct Option: B

The graft rejection takes place due to the presence of ________

  1. T cells

  2. B cells

  3. Mast cells

  4. None of the above


Correct Option: A

Consider the following four statements (A -D) regarding kidney transplant and select the two options that are true

(A) Even if a kidney transplant is proper the recipient may need to take immuno-suppresants for a long time.

(B) The cell-mediated immune response is responsible for the graft rejection.

(C) The B - lymphocytes are responsible for rejection of the graft.

(D) The acceptance or rejection of a kidney transplant depends on specific interferons.

The two correct statements are

  1. (A) and (B)

  2. (B) and (C)

  3. (C) and (D)

  4. (A) and (D)


Correct Option: A
Explanation:

Immunosuppressants are drugs/medicines that lower the immune system's ability to reject a transplanted organ. Even though the transplant is proper, it is always advised to continue taking immunosuppressant medication.
But when transplanted tissue is rejected by the recipient's immune system and destroys the transplanted tissue is called as graft rejection. Lymphocytes of specific cell-mediated immunity (T-cells) are responsible for graft rejection.

Patients who have undergone organ transplants are given anti-rejection medications to

  1. Minimize infection

  2. Stimulate B-macrophage cell interaction

  3. Prevent T-lymphocyte proliferation

  4. Adopt the $HLA$ of donor


Correct Option: C
Explanation:
  • The drugs that lower the immune system' are called immunosuppressants. 
  • These drugs are given to prevent graft rejection by lowering the immune system's ability to reject the transplanted organ. 
  • If immunity is not lowered the T lymphocytes which are the components of cell-mediated immunity destroy the transplanted tissue causing graft rejection. Thus the correct answer is option C.

Which of the following is correct for immuno-modulators?

  1. They always suppress immune system

  2. They never suppress immune system

  3. They always stimulate immune system

  4. Specific immuno-modulators stimulate the immuno response of immune system, whereas some other immuno-modulators inhibit it


Correct Option: D
Explanation:

Immuno-modulators are natural or synthetic substances that help to regulate or normalise the immune system. There are two types of immuno-modulators viz, immuno-suppressants, which cause immuno-suppression of the immune system and immuno-stimulants (immuno-stimulators) which stimulate immune system by inducing or increasing activity of any of its component. Thus the correct answer is option D.

Number of haplotypes present in an individual is 

  1. One

  2. Two

  3. Six

  4. Numerous


Correct Option: B
Explanation:

A haplotype (haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. It is used in the collection of specific alleles (that is, specific DNA sequences) in a cluster of tightly linked genes on a chromosome that are likely to be inherited together. An individual will have two haplotypes, although at a population level there may be numerous haplotypes for any given stretch of chromosomal DNA.

So, the correct answer is 'Two'.

Haplotypes are identical in

  1. Identical twins

  2. Brothers and sisters

  3. Children and parents

  4. All of the above


Correct Option: A
Explanation:

A haplotype (haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. It is used in the collection of specific alleles (that is, specific DNA sequences) in a cluster of tightly linked genes on a chromosome that are likely to be inherited together. The dizygotic twin pairs share two HLA haplotypes more often than ordinary siblings and thus might be genetically more alike.

So, the correct answer is 'Identical twins'.

Haplotype is

  1. A single genome

  2. Major histocompatability compklex

  3. Chain of HLA alleles inherited together

  4. All of the above


Correct Option: C
Explanation:

A haplotype (haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. It is used in the collection of specific alleles (that is, specific DNA sequences) in a cluster of tightly linked genes on a chromosome that are likely to be inherited together.

So, the correct answer is 'Chain of HLA alleles inherited together'.

In tissue typing for organ transplant, which of the following is matched?

  1. HLA proteins

  2. HLA alleles

  3. Human leucocyte antigens

  4. Haplotypes


Correct Option: C
Explanation:

The human leukocyte antigen (HLA) system or complex is a gene complex encoding the major histocompatibility complex (MHC) proteins in humans. These cell-surface proteins are responsible for the regulation of the immune system in humans. Tissue typing is a group of procedures that determine the type of histocompatibility antigens on a person's cells or tissues. This procedure is typically used prior to transplantation of tissues or organs. In tissue typing HLA (human leucocyte antigen) are matched.

So, the correct answer is 'Human leucocyte antigens'.