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High Resolution Protein Electrophoresis A Clinical Overview with Case Studies By Lawrence M. Killingsworth, Ph.D. Human Proteins Only ~200 of the vast array of human proteins have been characterized. Clinical knowledge is limited to 25 – 30 relatively high concentration components of plasma, CSF, urine and other fluids. Of these, 15 or so can be visualized by high resolution agarose electrophoresis. Normal Control Pre-albumin 1-Acid Glycoprotein -Lipoprotein 1-Antichymotrypsin Haptoglobin Albumin 1-Antitrypsin 2-Macroglobulin Transferrin -Lipoprotein C-3 Fibrinogen IgA IgG IgM Monoclonal Gammopathies Uncontrolled proliferation of a single clone of plasma cells at the expense of other clones. Protein analysis is valuable in diagnosing and monitoring lymphoproliferative diseases. Evaluation of Monoclonal Gammopathies 1. Serum and Urine High Resolution Protein Electrophoresis (24-hour urine preferred) 2. Quantitative Serum Immunoglobulins 3. Serum and Urine IFE SPIFE ImmunoFix IFE is the method of choice to identify suspicious serum or urine electrophoretic bands. Periodic evaluation by serum and urine electrophoresis and by quantitative Ig assay can help monitor therapy. Monoclonal Gammopathies Variable mobility and band appearance. Case 1: IgG Kappa Monoclonal Patient: 78 year-old male History & Physical: Severe pain right leg and right lumbar region. SPE: Monoclonal band in gamma region. IFE: IgG Kappa. Control Hospital Course: Bulging disk surgically decompressed; referred to hematologist/ oncologist for follow-up & treatment. Patient Case 2: IgG Kappa Monoclonal Patient: 78 year-old male History & Physical: Recent chemotherapy for lymphadenopathy. SPE: Hypoalbuminemia and monoclonal band in 2 region. IEP: IgG Kappa. Control Patient Hospital Course: Treated with transfusions and plasmapheresis. Symptomatic improvement. Discharged for outpatient re-evaluation. Case 3: IgA Lambda Monoclonal Patient: 74 year-old female History & Physical: Myeloma. Pain in lower thoracic and upper lumbar spine, right shoulder and left anterior ribs. SPE: Large monoclonal band in 2 region. IEP: IgA Lambda. Control Patient Hospital Course: Radiation therapy. Transferred to hospital closer to home for continued radiation and chemotherapy. Case 4: IgM Kappa Monoclonal Patient: 68 year-old male History & Physical: Anemia, elevated IgM, edema in ankles, petechiae. SPE: Marked M-component in 2 region; also in urine. IEP: IgM Kappa in serum; free Kappa light chains in urine. Control Patient Hospital Course: Bone marrow biopsy non-diagnostic. Discharged for outpatient treatment and followup for possible macroglobulinemia, chronic lymphatic leukemia or lymphoma. Case 5: Lambda Light Chain Patient: 78 year-old male History & Physical: Anemia, azotemia; admitted for dialysis. SPE: 1AT and Hp, pre-albumin, albumin & transferrin (consistent with acute inflammation); 2 small M-proteins in region. Urine: albumin,1AT, transferrin; large M-protein in region and smaller cathodal band. IEP: Monoclonal lambda light chain in urine and serum. No heavy chain. Control Patient Hospital Course: Bone marrow biopsy confirmed multiple myeloma. Hemodialysis, plasmapheresis and chemotherapy improved symptoms. Case 6: Lambda Light Chain Patient: 82 year-old male History & Physical: Fractured left hip, suspected frontal lobe infarction. SPE: albumin, acute inflammation, Hp (consistent with in-vivo hemolysis or RBC turnover), mild hypogammaglobulinemia. Urine: Several small monoclonal bands in region. IEP: Monoclonal free lambda light chain in urine; no monoclonal proteins in serum. Serum Control Urine Patient Hospital Course: Acute left cerebral infarction confirmed. B12 anemia treated. Died due to post-operative pneumonia following hip surgery. Multiple Myeloma Clinical Presentation Bone pain, especially in spine, pelvis or ribs Renal failure of unknown etiology Recurrent bacterial infections Physical exam usually unremarkable – no lymphadenopathy or hepatosplenomegaly Macroglobulinemia Clinical Presentation Fatigue Generalized weakness Skin and mucosal bleeding Visual disturbances Headache Other neurological signs and symptoms Cardiopulmonary abnormalities due to increased plasma volume and viscosity Recurrent bacterial infections Physical exam may reveal purpura, lymphadenopathy and hepatosplenomegaly Genetic Deficiencies 1-Antitrypsin Deficiency Linked to hepatitis and cirrhosis in neonates; chronic obstructive pulmonary disease and hepatic cirrhosis in adults Electrophoresis useful in initial evaluation Quantitative immunochemical assays and phenotyping required Genetic Deficiencies Immunoglobulin Deficiencies Isolated IgA deficiency Isolated IgM deficiency X-linked immunodeficiency with IgM Wiskott-Aldrich Syndrome Transient hypogammaglobulinemia of infancy Ataxia Telangiectasia Severe combined immunodeficiency (SKID) Common variable immunodeficiency –Pan hypogammaglobulinemia –IgG and IgA deficiency –Isolated IgG deficiency Inflammatory Response ACUTE SUBACUTE CHRONIC Pre-albumin Albumin ALPHA-1 -lipoprotein 1-acid glycoprotein 1-antitrypsin ALPHA-2 Cerulopasmin Haptoglobin BETA-1 Transferrin or N BETA-2 C-3 Fibrinogen or N IgA GAMMA IgM IgG CRP Liver Diseases Chronic Hepatocellular Disease & Cirrhosis Most common pattern includes diffuse increase in IgG with proportionally greater increases in IgA and sometimes IgM 1-antitrypsin is the most sensitive indicator for hepatocellular disease Pre-albumin is the most sensitive monitor in cirrhosis; 2-macroglobulin and ceruloplasmin also very elevated All other proteins usually normal or decreased Case 7: Chronic Hepatocellular Disease Patient: 39 year-old male Pre-albumin Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin C-3 Immunoglobulins Normal Patient History & Physical: Long-term alcohol abuse; ascites, leg swelling, shortness of breath, right side pain, enlarged liver and spleen. SPE: Hypoalbuminemia with normal migration. pre-albumin, -lipoprotein and transferrin, consistent with chronic disease. Diffuse IgA, IgG . Hospital Course: Ascites , right lung abcess treated. Liver tests normal at 4 weeks. Discharged in good condition. Liver Diseases Hepatitis Often associated with acute phase inflammatory response in the early stages Diffuse elevations in one or more of the immunoglobulins with chronic disease Case 8: Cirrhosis Pre-albumin Albumin Patient: 54 year-old female -Lipoprotein History & Physical: Chronic alcoholism; deeply jaundiced, rapid pulse, hepatomegaly, splenomegaly. 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin -Lipoprotein C-3 Immunoglobulins Normal Patient SPE: Hypoalbuminemia ( anodic mobility due to bilirubin binding). pre-albumin, -lipoprotein and transferrin, consistent with chronic disease. Diffuse IgA, IgG . Hospital Course: Rehydrated and stabilized. Discharged in good condition. Protein Losing Disorders Selective Protein Loss Nephrosis can result in elevations in serum concentrations of large proteins with decreases in smaller components. Serum pattern shows: – Increased 2-macroglobulin, -lipoprotein and polymeric forms of haptoglobin. – Decreased pre-albumin, albumin, 1-acid glycoprotein, 1-antitrypsin, transferrin. – IgM usually elevated, IgG usually decreased. Case 9: Acute Renal Failure Patient: 57 year-old male Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin -Lipoprotein C-3 Immunoglobulins Normal Patient History & Physical: Rapid onset abdominal pain and enlargement, edema, decreased urine output. SPE: albumin, 2-macroglobulin and -lipoprotein, consistent with selective protein loss due to glomerular-type proteinuria. Hospital Course: Received albumin and hemodialysis. Discharged in improved condition with limited outpatient dialysis. Final diagnosis: Acute renal failure due to tubular necrosis, possibly of a toxic nature. Protein Losing Disorders Nonselective Protein Loss Whole blood loss Congestive heart failure Liver failure Hemodilution Malnutrition Protein-losing enteropathies – greater decrease in immunoglobulins than other plasma proteins Pregnancy & Hyperestrogenism* Moderate decreases in prealbumin, albumin, 1-acid glycoprotein and IgG Large relative increases in 1-antitrypsin, ceruloplasmin, transferrin and fibrinogen Moderate increase in -lipoprotein Slight increase in 2-macroglobulin and hemopexin Haptoglobin and C-3 essentially normal *Hyperestrogenism (i.e. contraceptive pills, estrogen medications) can mask pathological changes Case 10: Infant w/ Hepatic Involvement Patient: 5 month-old female Pre-albumin Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin C-3 Immunoglobulins Normal Patient History & Physical: Previously healthy; 104º fever/24 hrs, jaundice, hepatomegaly. SPE: Hypoalbuminemia ( anodic mobility due to bilirubin binding), 1-AT, Hp, -lipoprotein, transferrin; consistent with acute inflammation. Age-appropriate hypogammaglobulinemia. Hospital Course: Blood culture positive for gram negative rods. Treated with antibiotics and discharged. Case 11: Acute Renal Failure Pre-albumin Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin C-3 Immunoglobulins C-reactive protein Normal Patient Patient: 52 year-old male History & Physical: Weakness, progressive shortness of breath, tachycardia, anemia, azotemia, mild hepatomegaly, edema. SPE: Hypoalbuminemia, 1-AT, Hp, -lipoprotein, transferrin; consistent with acute inflammation. Low normal gammaglobulins. CRP? Hospital Course: Blood culture positive for Staph aureus. Vigorous antibiotic therapy. Died 5 days postadmission. Case 12: Chronic Renal Failure Patient: 68 year-old male Pre-albumin Albumin -Lipoprotein 1Antitrypsin 2-Macroglobulin Haptoglobin Transferrin -Lipoprotein C-3 Immunoglobulins Normal Patient History & Physical: Chronic bladder outlet obstruction; abdominal pain, hematuria, urinary or bladder infection. SPE: Hypoalbuminemia with anodal mobility; 1-AT, Hp, transferrin; consistent with acute inflammation. Random urine pattern consistent with mixed glomerular-tubular proteinuria. Hospital Course: Continued antibiotics, hemodialysis. Case 13: Acute & Subacute Inflammation Pre-albumin Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin -Lipoprotein C-3 Immunoglobulins Normal Patient Patient: 74 year-old male History & Physical: Pneumonia, 2 weeks duration. SPE: Hypoalbuminemia with anodal mobility; 1-AT, Hp, transferrin, a-lipoprotein, and C-3; consistent with acute and subacute inflammation. Hospital Course: Antibiotics, discharged in good condition. Case 14: Diffuse Hypergammaglobulinemia with Lymphoma Pre-albumin Albumin -Lipoprotein 1-Antitrypsin 2-Macroglobulin Haptoglobin Transferrin -Lipoprotein C-3 Immunoglobulins Normal Patient Patient: 63 year-old female History & Physical: Pruritis, sweats and fatigue, multiple dermal nodules. SPE: Non-specific findings – diffuse increase in immunoglobulins, suggesting chronic inflammation. Hospital Course: Biopsy reports consistent with lymphoma; patient discharged for outpatient treatment and followup. Urinary Proteins of Plasma Origin Normal Urinary Protein < 150 mg/day Albumin Primarily Filtered Plasma Proteins – albumin, low MW species, immunoglobulin components Sometimes Transferrin Remainder – derived from urinary tract Urine Serum Electrophoretic pattern of normal urine – trace albumin, sometimes transferrin Urinary Proteins of Plasma Origin Proteinuria Glomerular – results from increased passage of proteins through the glomerulus; characterized by loss of plasma proteins the size of albumin or larger Tubular – results from decreased capacity of tubules to reabsorb proteins; characterized by inceased excretion of very small proteins such as 2-microglobulin Systemic – exercise, postural, pregnancy, overflow Urinary Proteins of Plasma Origin High Resolution protein electrophoresis developed with a sensitive protein stain Excellent analytical technique Easily distinguishes & characterizes the various types of proteinuria Provides useful insight on specific functions within the nephron “Biochemical biopsy” Differential diagnosis & monitoring of patients with renal dysfunction Urinary Proteins of Plasma Origin Glomerular Proteinuria Renal glomeruli are ultrafilters for macromolecules Damage to renal glomeruli leads to increased urinary excretion of proteins (30,000 to 100,000 daltons) which are normally retained Some selectivity remains – very large proteins (>500,000 daltons) still retained by glomerulus In early disease, very LMW proteins (<15,000 daltons) are still reabsorbed by tubules and absent from urine Urinary Proteins of Plasma Origin Glomerular Proteinuria Urine Protein Pattern - strong band of albumin - strong, broad 1 zone due to 1-acid glycoprotein and 1-antitrypsin - strong band of transferrin (1) Serum Protein Pattern - marked decrease in albumin - marked decrease in 1-acid glycoprotein and 1-antitrypsin - increases in large proteins: 2-macroglobulin, -lipoprotein Urinary Proteins of Plasma Origin Severe Proteinuria / Nephrotic Syndrome Total Protein > 3.5 g/day Hypoalbuminemia and hyperlipidemia Massive edema Urinary Proteins of Plasma Origin Disorders Associated with Nephrotic Syndrome Glomerular diseases Proliferative glomerulonephritis Other diseases - Infections - Neoplasia - Miscellaneous - Drugs - Multisystem diseases - Hereditary disorders Case 1: Nephrotic Syndrome with Glomerular Proteinuria Patient: 45 year-old white male Albumin Albumin 1 acid glycoprotein 1AT 2-Macro 1 AT HP Transferrin Transferrin -Lippo C-3 IgA IgM IgG Normal Serum Urine History & Physical: Diabetes mellitus / nephrotic syndrome. SPE: pre-albumin, albumin and transferrin with 2-macroglobulin and -lipoprotein; consistent with selective renal protein loss. Urine Elp: albumin, 1-antitripsin and transferrin with trace pre-albumin and 2-components; consistent with sieving glomerular-type protein loss. Urinary Proteins of Plasma Origin Tubular Proteinuria Normal tubules reabsorb and catabolize 95 to 99% of proteins from glomerular filtrate Tubular disease reduces capacity to reabsorb and catabolize, resulting in increased urinary excretion Causes of tubular proteinemia: - Chronic metal exposure (cadmium, gold, lead, mercury) - Acute and chronic pyelonephritis - Renal transplant rejection - Toxicity due to aminoglycoside therapy - Balkan nephropathy - Uremic medullary cystic disease Urinary Proteins of Plasma Origin Tubular Proteinuria Serum Protein Pattern - little or no change since LMW proteins are present in very low levels Urine Protein Pattern - faint albumin band - double band in 2 area due to 2-microglobulin - strong band in mid- region due to 2-microglobulin - diffuse background in region due to free light chains Urinary Proteins of Plasma Origin Mixed Glomerular/Tubular Proteinuria Chronic renal disease or renal failure Combined pattern with both “glomerular-type” and “tubular-type” proteins in the urine Case 2: Heavy Metal Toxicity with Tubular Proteinuria Albumin Albumin 1-AT 2-Macro 2Microglobulin HP 2Microglobulin Transferrin -Lipo Patient: 52 year-old black male History & Physical: Metal worker. SPE: Essentially normal. Urine Elp: Trace albumin, 2-microglobulin and 2-microglobulin; consistent with tubular-type proteinuria. C-3 IgA IgM IgG Normal Serum Urine Urinary Proteins of Plasma Origin Other Conditions with Increased Urinary Protein Excretion Exercise Proteinuria – strenuous muscular exercise increases excretion of HMW and LMW proteins Postural or Orthostatic Proteinuria – present/upright, absent/recumbent – benign or underlying cause? Pregnancy – usually transitory, may be associated with toxemia, delivery, UTI, or asymptomatic Overflow Proteinuria – increased plasma concentration of LMW proteins, e.g. BJP, myoglobin, hemoglobin, acute phase reactants Case 3: Septicemia with Overflow Proteinuria Patient: 65 year-old white female Albumin Albumin 1-acid glycoprotein 1AT 1-AT 2-Macro Acute phase reactants HP Transferrin -Lipo C-3 IgA IgM IgG Normal Serum Urine History & Physical: High fever, chills, sweats, joint and muscle aches. SPE: pre-albumin, albumin, -lipoprotein and transferrin, 1-antitrypsin, haptoglobin, C3 & C-reactive protein; consistent with acute inflammation. Urine Elp: Trace albumin and transferrin, 1-acid glycoprotein, faint acute phase reactants; consistent with overflow proteinuria Cerebrospinal Fluid Proteins CSF Proteins versus Plasma Proteins CSF Total Protein: Much less than in plasma 150 – 450 mg/L, ages 10 – 40 years, lumbar Slightly higher, ages 40+ Slightly higher for verticular & cisternal specimens CSF Production: Primarily ultrafiltration and active transport of proteins, ions, water and other components through the choroid plexus. Small amount produced within CNS Cerebrospinal Fluid Proteins CSF Protein Composition Pre-albumin Albumin – major protein present, 55 – 75% of the total Albumin 1-Antitrypsin 1 – primarily 1-antitrypsin, -lipoprotein absent Haptoglobin Transferrin CSF 2 – essentially absent TF 1 – transferrin detectable 2 – carbohydrate-deficient “CSF-specific” transferrin Oligoclonal Bands Normal CSF Abnormal Patient CSF – almost exclusively IgG, faint “-trace” Cerebrospinal Fluid Proteins Permeability of Blood-CSF Barrier Increased permeability caused by - bacterial or viral menigitis - neoplastic infiltration of meninges - polyneuropathies - disk herniations - cerebral infarctions Integrity of blood-CSF barrier - Total CSF protein - 2-macroglobulin - Protein ratios Cerebrospinal Fluid Proteins Abnormal CNS Protein Production Demyelinating Diseases Increased IgG synthesis in Multiple Sclerosis and Subacute Sclerosing Panencephalitis IgG as Percentage of Total Protein Considers increased permeability vs. synthesis. IgG >10% suspicious; >13% abnormal production likely. CSF/Serum Ratios Considers increased plasma concentration. 86% of MS patients show values above reference range. Oligoclonal Banding Indicative of MS; new more sensitive procedure is IEF. Cerebrospinal Fluid Proteins Oligoclonal Banding Multiple, restricted bands in the gamma fraction Detectable by high resolution electrophoresis and IEF methods 90% of MS patients exhibit oligoclonal banding New CSF IEF methods have become the gold standard for diagnosing MS in Europe. Cerebrospinal Fluid Proteins Isoelectric Focusing IEF followed by immunoblotting Oligoclonal banding in unconcentrated CSF but not serum is diagnostic of MS Gold Standard in Europe S = Serum C = CSF Cerebrospinal Fluid Proteins Laboratory Protocol to Rule Out MS 1. Draw both CSF and serum samples. 2. Note CSF color and appearance. Determine total protein, glucose, white cell count, differential, red cell count. 3. Perform high resolution protein electrophoresis on concentrated CSF. 4. Perform high resolution protein electrophoresis on serum for presence or absence of banding. 5. In borderline cases, determine CSF and serum albumin and IgG ratios. Cerebrospinal Fluid Proteins Laboratory Findings in Multiple Sclerosis CSF Appearance: Clear NSC Patient Serum Leukocytes: Usually normal Total Protein: Usually normal Glucose: Normal Patient CSF Electrophoresis: Oligoclonal banding in 90% of cases Normal CSF IgG Ratio: Elevated in 90% of cases Cerebrospinal Fluid Proteins Clinical Manifestations of MS 40% of patients present with optic neuritis 60 to 70% present with evidence of spinal cord or brainstem lesion Case 1: Multiple Sclerosis Patient: 33 year-old female Normal CSF Patient CSF Patient Serum NSC History & Physical: left-side numbness - 9 months; fuzzy vision - 2 weeks. SPE: Normal. CSF: Clear, colorless. Cell count, differential, glucose and total protein all normal. CSF Elp: Increased gamma globulins, strong oligoclonal banding. Consistent with demyelinating disease. Case 2: Multiple Sclerosis Patient: 31 year-old male Normal CSF Patient CSF History & Physical: Unsteady walk, leg numbness, inability to concentrate, irritability, slurred speech, disturbed vision, urinary urgency. SPE: Normal. Patient Serum NSC CSF: Clear, colorless. Normal glucose. 29 WBC/mm3 (9% lymphocytes, 1% moncytes). Total Protein 55 mg/dL. CSF Elp: Gamma globulin increase, strong oligoclonal banding; consistent with MS. Case 3: Multiple Sclerosis Patient: 36 year-old female Normal CSF Patient CSF History & Physical: numbness in legs – 1 month; urinary urgency and blurred vision – 4 months; tires easily. SPE: Normal. Patient Serum NSC CSF: Clear, colorless. Normal total protein, WBC count, and glucose. CSF Elp: Profound gamma globulin increase, very strong oligoclonal banding. (IgG & ratios markedly elevated.) Consistent with MS. Case 4: Suspected Viral Meningitis Patient: 25 year-old white female Normal CSF Patient CSF Patient Serum NSC History & Physical: Progressive headache, lethargy, altered mental status; “flu” – 4 weeks prior. SPE: Borderline hypoalbuminemia. CSF: Clear, colorless. Normal glucose. 158 WBC/mm3 (1oo% moncytes). Total Protein 83 mg/dL. CSF Elp: Increased gamma globulins, prominent oligoclonal banding. Considering total protein; consistent with viral encephalitis. Discharged for outpatient followup. Case 4: Suspected Viral Meningitis (cont’d) Patient: Readmitted 8 days later with redeveloped headache. Normal CSF Patient CSF Patient Serum NSC Normal CSF Patient CSF CSF: Clear, colorless. Normal glucose and protein. 103 WBC/mm3 (90% lymphocytes, 10% neutrophils). CSF Elp: Gamma globulins and oligoclonal banding decreased from previously. Transient increase consistent with CNS infection / inflammation. SPIFE 3000 Analyzer Automated sample application, separation and staining of visible analytes Automated reagent application for enzymatic assays On-board cooling for excellent separation and resolution On-board availability of two stains SPIFE Assays Cholesterol Profile Serum Proteins Split-Beta SPE Urine Proteins Immunofixation Urine Immunofixation Hi Resolution Proteins Alkaline Hemoglobins Acid Hemoglobins CK* & LD Isoenzymes Alk Phos Isoenzymes* CSF IgG IEF* Lipoproteins *Pre-market approval pending 4/02 SPIFE Hi Res Proteins Excellent separation Active cooling preserves pattern integrity Acid violet stain for added sensitivity Urine SPIFE IFE 15, 9, 6 & 3 Up to 210 profiles in 8 hours Highest sensitivity antisera Acid violet for best sensitivity Built in QC wells An educational service of: 1-800-231-5663 www.helena.com