Severe+Combined+Immunodeficiency+(SCID)

__**Severe Combined Immunodeficiency (SCID) **__


 * Root Cause: **

Enzymatic deficiency of adenosine deaminase.


 * Affected cell types/tissues/organs/systems: **

Affects all cell types (inability to make new DNA); severely affects immune system, T- and B-lymphocyte systems.




 * Historical Background: **

In 1952, military pediatrician Colonel Ogden Bruton a case of agammaglobulinemia (inability to form antibodies). A better understanding of the disease led to it being categorized as a primary immunodeficiency disease, given the name Swiss-type agammaglobulinemia. Further research and collaboration led to an even better understanding of this disease, which is now known as severe combined immunodeficiency, or SCID [1].

The most famous victim of SCID is David Vetter, or the ‘bubble boy”. Vetter, whose brother died from SCID, was born into a sterile environment and spent the first 12 years of his life in a germ free bubble. With the advice from his doctors, David left the bubble shortly after his 12th birthday to receive bone marrow treatment. Fifteen days removed from the bubble, David died [2].


 * Common Symptoms: **

No immune system, therefore body is subject to any/all forms of infections and disease. Common life threatening infections related to SCID include pneumonia, meningitis, and various bloodstream infections [3].


 * Standard Treatments: **
 * Bone marrow transplant
 * Bubbles
 * Gene therapy


 * Current Research: **

In 2012, a study showed that retrovirus-based correction of SCID worked as an effective form of gene therapy for two types of SCID (SCID-X1 and adenosine deaminase)[4].

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">Most infants with SCID lack a family history of the disease, which raises questions whether this fatal disease should be a candidate for population based newborn screening. A 2012 study has shown that testing for T-cell receptor excision circles (TRECs), biomarkers of normal T-cell development, is a successful screening technique for SCID [5].


 * <span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">References: **

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">[1] Silverstein, A. M. (2009). A History of Immunology. (2nd ed., p. 404). New York, NY: Academic Press.

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">[2] PBS. (2006, March 06). The Boy in the Bubble. Retrieved from [].

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">[3] Ballard, B. (2010). Severe combined immunodeficiency. Retrieved from [].

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">[4] Fischer et al. (2012). Strategies for retrovirus-bases correction of severe, combined immunodeficiency (SCID). Methods in Enzymology, 507, 15.

<span style="font-family: 'Times New Roman',Times,serif; font-size: 140%;">[5] Puck, J. M. (2012). Laboratory technology for population-based screening for severe combined immunodeficiency in neonates: The winner is t-cell receptor excision circles. The Journal of Allergy and Clinical Immunology, 29(3), 607-616.