Immunodeficiency (SCID):


Serves combine immunodeficiency

Describe and explain.
SCID (serves combine immunodeficiency) means you are missing your body defense system. They are caused by a mutation a gene that affects the immune system. Each parent carries a normal copy of the gene and an abnormal copy. So the children how has this disease are going to have two abnormal copy of gene.


Severe defect in T cell production and function, with defects in B-Lymphocytes are always the defining characteristic for SCID and, in some genetic type, in NK cell production as well.


Some types of SCID are caused by a mutation of a gene on the X chromosome, which comes from the mother. (x-scid) A female with the mutated gene will not have the disease but will be a carrier. This means she may pass the mutated gene on to her children.


About T and B cell
When a foreign antigen comes into your body, the T-helper cell direct B-cell will make some antibodies to against it.
There are 3 main forms of T-Lymphocytes: Helper, cytotoxic and regulatory T cells.
  • Helper: makes all other immune cells to attack foreign antigens.
  • Cytotoxic: kills the unwanted antigens
  • Regulatory: the off- switch to an attack.


Serves combine immunodeficiency is a very rare congenital disorder.

There are T-, B+ SCID; T-, B+, NK- SCID; AND T-, B-, NK- SCID. Among all these, the ‘T-, B+, NK- SCID’ is the most common one.

According to the inheritance pattern, T-, B+, NK- SCID can divided into two types: x-linked and autosomal recessive


Autosomal recessive inheritance
When a baby inherits 2 defective copy of the same autosomal gene causes the Autosomal recessive forms of SCID. The parents of the baby who has the disease each carry one normal copy of the gene and one abmormal copy. And the baby inherits the 2 abnormal copies.
ADA deficiency is a form of SCID. ADA deficiency is a lack of enzyme which can helps cells to get rid of toxic byproducts. The predominance patients of ADA deficiency are male, but actually, ADA deficiency has an AR inheritance pattern affects male and female equally.


X-SCID
X-SCID only occurs in males. X-SCID is caused by a mutation of a gene on the X chromosome, which comes from the mother. A female with a mutated gene will not have the disease, but will be the carrier, and pass the defective gene to her child.


Limitation

Patient of SCID will die of opportunistic infections before their first or second birthday.
Patient may have otitis media, pneumonia, sepsis, diarrhea and skin infection after a few months after birth.


Experts cost of prolonged ICU admissions in connection with SCID total $1 million or more. They spent a lot of money to learn about SCID, and found out a lot of way to treat it, so this helped our society a lot. Bone marrow transplantation, bubbles and gene therapy, those are all the treatments for SCID. The most common way is bone marrow transplantation. And the costs of bone marrow transplantation are really high, so this also does something to the economic.
SCID_Gene_Therapy.jpg





"The SCID Homepage." The SCID Homepage. Web. 12 Mar. 2012. <http://www.scid.net/>.

"Learning About Severe Combined Immunodeficiency (SCID)." National Human Genome Research Institute (NHGRI). Web. 12 Mar. 2012. <http://www.genome.gov/13014325>.

"联合免疫缺陷." 联合免疫缺陷疾病概述. Web. 12 Mar. 2012. <http://www.jkwhy.cn/ailment/neike/1743.htm>.