IgG IEF Diagnosing Multiple Sclerosis

Multiple Sclerosis CNS disorder Scar formation on outside of nerve cells of brain and spinal cord Inflammation destroys covering of nerve cells leaving scar tissue Nerve cells cannot transmit impulses

Prevalence Onset at age 15 to 50 years 70% female Temperate climate predominant

Symptoms Optic neuritis Numbness / weakness in extremities Instability in walking Tremors Loss of bladder control Heat intolerance Fatigue

Diagnosis by Exclusion Encephalitis CNS Vasculitis Lyme Disease Behet Syndrome Sarcoidosis Syphilis Leukodystrophies Lupus Erythematosus Spastic Paraparesis Vitamin B-12 Deficiency Sjogren’s Syndrome Hereditary Degenerative Disorder Multifocal Leukoencephalopathy

Criteria for Diagnosis History of two attacks with positive oligoclonal bands or increased IgG in CSF

Criteria for Diagnosis History of two attacks with no laboratory abnormality

Criteria for Diagnosis History of two attacks with clinical and paraclinical evidence of lesions, oligoclonal bands, and increased IgG in CSF

Criteria for Diagnosis History of two attacks with clinical evidence of at least one lesion, and clinical or paraclinical evidence of another lesion

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field Proteins exhibit net + or – charge

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field Proteins exhibit net + or – charge Migrate toward electrode of opposite charge

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field Proteins exhibit net + or – charge Migrate toward electrode of opposite charge Rate of migration ↓ as it reaches isoelectric point

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field Proteins exhibit net + or – charge Migrate toward electrode of opposite charge Rate of migration ↓ as it reaches isoelectric point (pI) Protein focuses at pI

IEF Theory Stable pH gradient with carrier ampholytes in an electrical field Proteins exhibit net + or – charge Migrate toward electrode of opposite charge Rate of migration ↓ as it reaches isoelectric point (pI) Protein focuses at pI; some drift but regains charge and migrates back

IEF Procedure Step 1: Focus proteins

IEF Procedure Step 2: Transfer proteins to nitrocellulose membrane

IEF Procedure Step 3: React with IgG antisera

IEF Procedure Step 4: React with chromagen Step 5: Air dry Total Time: 2.5 to 3.0 hours

Interpretation Compare CSF and Serum Looking for intrathecal synthesis indicated by oligoclonal bands in CSF but not in serum

Interpretation Negative – no oligoclonal bands in CSF

Interpretation Mirror Image – same bands in CSF and serum

Interpretation Positive – Oligoclonal bands in CSF but not in serum

Interpretation Positive oligoclonal banding is not diagnosis of MS