1.
Defect in integrins causing high neutrophils in blood but poor migration into tissues or defective fucosyltransferase preventing selectin-mediated rolling of leukocytes.
2.
No respiratory burst due to NADPH oxidase defect.
3.
Enzyme missing in chronic granulomatous disease.
4.
High IgM with low IgG, IgA, and IgE from failed class switching.
5.
Low antibody levels with normal B-cell count but failure to differentiate into plasma cells.
6.
Severe combined immunodeficiency with absent T-cell function and defective B-cell responses.
7.
Common cytokine receptor chain mutated in X-linked SCID.
8.
Enzyme deficiency causing toxic metabolite buildup and impaired lymphocyte DNA synthesis.
9.
Purine metabolism defect leading to decreased lymphocytes.
10.
Recombinase enzyme defect preventing VDJ recombination in developing lymphocytes.
11.
Transporter needed for peptide loading onto MHC class I.
12.
Secondary immunodeficiency caused by lack of essential nutrients.
13.
Drug exposure causing iatrogenic immunosuppression by killing dividing immune cells.
14.
Medical treatment that destroys rapidly dividing cells, including immune cells.
15.
Tyrosine kinase missing in X-linked agammaglobulinemia.
16.
No mature B cells and severely reduced antibodies due to BTK mutation.
17.
Virus that destroys CD4 T cells causing secondary immunodeficiency.
18.
Advanced stage of HIV infection with fewer than 200 CD4 T cells.
19.
Age group with immature immune system relying heavily on maternal antibodies.
20.
Age group with reduced naïve T cells and lower vaccine response.
