Immunology

Steps

1. 1Innate and adaptive immunity15 min · Tell innate from adaptive immune cells by their receptors and memory · Name where lymphocytes develop and where they first meet antigen · Match MHC class I and class II presentation to the CD8 or CD4 T cell they activate · Explain how a secondary antibody response differs from a primary response
2. 2Antibody structure and classes13 min · Match Fab and Fc fragments to antigen binding and effector function · Match an immunoglobulin class to its distribution and immune function · Distinguish single-site affinity from total binding avidity
3. 3Lattices, prozone and agglutination16 min · Recognize antibody excess as a cause of weak agglutination · Recognize antigen excess as a cause of a falsely low immunoassay result · Read direct and inhibition agglutination using the assay's controls
4. 4Complement16 min · Distinguish classical, lectin, and alternative complement initiation · Match a complement fragment to its principal immune effect · Interpret paired CH50 and AH50 results to locate a complement defect · Check that a CH50 or AH50 specimen was separated and frozen promptly before accepting it
5. 5Labeled immunoassays and immunofluorescence15 min · Predict labeled-assay signal direction from the binding format · Distinguish direct from indirect immunofluorescence by the labeled reagent · Distinguish cytokine concentration from counts of cytokine-secreting cells
6. 6Tolerance, ANA and systemic autoimmunity16 min · Distinguish central from peripheral mechanisms of self-tolerance · Interpret an ANA pattern and titer without assigning an unmeasured specificity · Match systemic autoantibodies such as ANA, anti-dsDNA, and anti-Sm to their diseases
7. 7Thyroid, rheumatoid and organ-specific autoantibodies15 min · Choose the antibody tests that fit a suspected organ-specific disease · Tell thyroid antibody results from thyroid function, and TRAb binding from stimulation · Tell a nonspecific rheumatoid factor result from a more specific anti-CCP result
8. 8Hypersensitivity and allergy testing15 min · Classify a hypersensitivity reaction by its main effector mechanism · Distinguish allergen sensitization from clinical allergy · Compare an acute tryptase with the patient's own baseline
9. 9Plasma cell disorders, cryoglobulins and tumor immunity16 min · Tell MGUS from myeloma by M protein, marrow plasma cells, and myeloma-defining events · Reject a cryoglobulin specimen that was not kept warm until separation · Predict how tumor-antigen or HLA class I loss changes T-cell and NK-cell attack
10. 10Immunodeficiency16 min · Choose first tests for a suspected antibody, T-cell, or phagocyte deficiency · Recognize when low immunoglobulins or lymphocytes need tests for an inherited deficiency · Send a low TREC newborn screen for lymphocyte subsets and confirmatory testing
11. 11HLA typing and crossmatching17 min · Calculate sibling HLA-haplotype sharing probabilities · Distinguish recipient attack on a graft from graft-versus-host injury · Report HLA typing only to the allele resolution the typing method reached · Tell single-antigen bead HLA antibody results from a donor-cell crossmatch
12. 12Hepatitis B, C and D serology16 min · Read HBsAg, anti-HBs, and anti-HBc together to classify hepatitis B status · Choose RNA follow-up to determine current hepatitis C infection · Distinguish HDV exposure from current infection in a person with HBV · Apply each infection's own IgM and paired-titer timing rules to a serology result
13. 13EBV, CMV and varicella serology15 min · Call EBV infection recent or past from VCA IgM, VCA IgG, and EBNA antibody · Choose the CMV test for past exposure, current replication, or congenital infection · Choose lesion PCR or VZV IgG to tell current infection from past immunity
14. 14The HIV testing algorithm16 min · Choose the next laboratory test in the HIV diagnostic algorithm · Recognize when recent exposure or antiretroviral use limits HIV detection · Choose virologic testing for an infant with possible perinatal HIV exposure
15. 15Viral load and CD4 counts14 min · Distinguish what an HIV viral load measures from what a CD4 count measures · Calculate a CD4-to-CD8 ratio from comparable absolute counts
16. 16Syphilis testing16 min · Choose the next test for a reactive treponemal screen with a nonreactive RPR · Call a fourfold RPR or VDRL titer change only between results from one method · Report a negative CSF VDRL without excluding neurosyphilis
17. 17Lyme and tuberculosis testing15 min · Read Lyme two-tier results, counting an IgM blot only in the first 30 days of illness · Interpret an IGRA with its controls and limits for active tuberculosis

What you'll be able to do