MHC Class 3

Question.

208. MHC class 3 Genes Encode;

1. Complement Component C3

2. Tumor necrosis factor.

3. Interleukin 2.

4. Beta 2 microglobulin.

Answer

2. Tumor necrosis factor.

Reference

Harrison's15^th Edition,Pg-1832 Chapter 306

Ananthanarayanan 5^th Edition Page 118

Ananthanarayanan 6^th Edition Page 120,121

Quality

Thinker

Status

New

QTDF

Ananthanarayanan

Discussion

Please note that Human MHC antigens are synonymous with Human Leucocyte Antigen(HLA) and MHC Complex of genes with HLA Complex

The HLA class III region is a name given to a

• cluster of genes between the class I and class II complexes,
• which includes genes
• for the two closely related cytokines
• tumor necrosis factor (TNF-alpha) and
• lymphotoxin (TNF-beta);
• the complement components
• C2,
• C4, and
• Bf;
• heat shock protein (HSP)70; and
• the enzyme 21-hydroxylase

Explanation

1. Complement Component C3 is not coded by HLA III. Instead only C2 and C4 are coded by HLA III

2. Tumor necrosis factor, is coded by HLA III.

3. Interleukin 2 is not coded by HLA III.

4. Beta 2 microglobulin is not coded by HLA III.

Comments

A question directly from Ananthanarayanan, yet could be easily missed

Tips

Immunology from Ananthanarayanan may look simple and nominal, but most questions can be answered from Ananthanarayan alone