BCR TBL 11 - Pathology of Lymphoid Cells

Where do B cells mature?

Bone marrow

Where do T cells mature?

Thymus

What process eliminates self-reactive T cells?

Negative selection

What process ensures T cells recognize self-MHC?

Positive selection

What gene is essential for B-cell commitment?

Pax5

What enzyme mediates V(D)J recombination?

RAG1/RAG2

Which cytokine is crucial for T-cell development?

IL-7

What is the function of the AIRE gene?

Promotes expression of self-antigens for T-cell tolerance

What is the first stage of B-cell development?

Pro-B cell

Which transcription factor promotes T-cell lineage?

Notch1

What is a common viral cause of lymphocytosis?

Epstein-Barr virus (EBV)

Name a bacterial cause of lymphocytosis.

Bordetella pertussis

What autoimmune condition can cause lymphopenia?

Systemic lupus erythematosus (SLE)

What is a drug-induced cause of lymphopenia?

Corticosteroids

What congenital condition leads to both B and T cell deficiency?

Severe Combined Immunodeficiency (SCID)

What virus causes selective CD4+ T-cell loss?

HIV

What condition shows persistent lymphocytosis and smudge cells?

Chronic Lymphocytic Leukemia (CLL)

Which cytokines guide lymphocyte homing to lymph nodes?

CCL19 and CCL21

What is a common cause of generalized lymphadenopathy?

HIV infection

What test distinguishes clonal vs polyclonal lymphadenopathy?

Flow cytometry

What is a hallmark of malignant lymphadenopathy?

Clonal proliferation

What type of lymphadenopathy is typical in localized infection?

Localized lymphadenopathy

What type of lymphadenopathy is seen in lymphoma?

Generalized lymphadenopathy

What feature distinguishes reactive from malignant nodes?

Architecture preservation in reactive nodes

What infection is associated with posterior cervical lymphadenopathy?

EBV (Infectious mononucleosis)

What histological pattern suggests follicular lymphoma?

Nodular growth pattern

What virus is associated with Burkitt lymphoma?

Epstein-Barr virus

What lymphoma has t(14;18) translocation?

Follicular lymphoma

What lymphoma shows CD15+ and CD30+ markers?

Hodgkin lymphoma

Which lymphoma subtype presents with jaw swelling in children?

Endemic Burkitt lymphoma

What is the classic cell in Hodgkin lymphoma?

Reed-Sternberg cell

Which Hodgkin subtype is most common?

Nodular sclerosis

Which subtype of NHL is most aggressive?

Diffuse Large B-cell Lymphoma (DLBCL)

Which lymphoma has a starry sky appearance?

Burkitt lymphoma

What infection is associated with MALT lymphoma?

Helicobacter pylori

Which marker is typically positive in DLBCL?

CD20

What is the translocation in Burkitt lymphoma?

t(8;14)

Which lymphoma is CD5+ but CD23-?

Mantle cell lymphoma

Which lymphoma is indolent and presents with waxing/waning lymphadenopathy?

Follicular lymphoma

Which lymphoma can be cured by treating H. pylori?

MALT lymphoma

What cell marker is shared between CLL and mantle cell lymphoma?

CD5

What marker differentiates CLL from mantle cell lymphoma?

CD23

What chromosomal deletion indicates poor prognosis in CLL?

del(17p)

What is a common complication of CLL related to immunity?

Hypogammaglobulinemia

What syndrome describes transformation of CLL to aggressive lymphoma?

Richter's transformation

What is a typical blood smear finding in CLL?

Smudge cells

Which gender and age group is most affected by CLL?

Older males

What test confirms CLL diagnosis?

Flow cytometry

What is the most common leukemia in adults?

Chronic Lymphocytic Leukemia (CLL)

Which marker indicates better prognosis in CLL?

del(13q)

What is the hallmark finding in multiple myeloma?

Monoclonal plasma cell proliferation

What are the CRAB criteria?

Calcium elevation, Renal failure, Anemia, Bone lesions

What protein is found in urine in multiple myeloma?

Bence-Jones protein

What causes renal failure in multiple myeloma?

Light-chain cast nephropathy

What type of immunoglobulin is most common in MM?

IgG

What is a precursor to multiple myeloma?

MGUS

What percentage of plasma cells is diagnostic for MM?

10%

What condition shows M-protein but no symptoms?

MGUS

What is the typical bone imaging used in MM?

Skeletal survey (X-ray)

What syndrome is caused by IgM in Waldenström’s?

Hyperviscosity syndrome

What is the main difference between MGUS and MM?

Absence of end-organ damage in MGUS

What immunoglobulin is elevated in Waldenström?

IgM

Which plasma cell disorder does not cause bone lesions?

Waldenström macroglobulinemia

What is used to detect M-protein in plasma?

Serum protein electrophoresis

What causes blurry vision and headache in WM?

Hyperviscosity

Which plasma cell disorder causes anemia and lytic bone lesions?

Multiple myeloma

What plasma cell disorder may present with neuropathy?

Waldenström macroglobulinemia

What test is used to confirm plasma cell % in bone marrow?

Bone marrow biopsy

What is a risk factor for MGUS progressing to MM?

High M-protein level

What distinguishes smoldering MM from active MM?

No CRAB symptoms in smoldering MM

What does positive selection of T cells ensure?

Recognition of self-MHC

Where does positive selection of T cells occur?

Thymic cortex

What does negative selection of T cells prevent?

Autoimmunity

Where does negative selection of T cells occur?

Thymic medulla

Which cells mediate negative selection of T cells?

Medullary thymic epithelial cells

What transcription factor controls self-antigen expression in the thymus?

AIRE

What receptor is rearranged during early B-cell development?

Immunoglobulin heavy chain

What is the marker of immature B cells?

Surface IgM

Which lymphocyte type undergoes somatic hypermutation?

B cells

Where does somatic hypermutation occur?

Germinal centers

What process leads to isotype switching in B cells?

Class switch recombination

Which enzyme is needed for somatic hypermutation?

AID (activation-induced deaminase)

What is a key feature of mature naive T cells?

CD3+, CD4+ or CD8+

Which cell type provides help to B cells in germinal centers?

CD4+ T follicular helper cells

What cytokine is essential for B-cell survival?

BAFF

Which type of infection typically causes lymphocytosis?

Viral infection

What is the typical lymphocyte response in EBV infection?

Atypical reactive CD8+ T cells

What are Downey cells?

Reactive lymphocytes seen in EBV infection

Which test is used to confirm EBV mononucleosis?

Monospot test

What is the main cell target of EBV?

B cells

Which virus is associated with post-transplant lymphoproliferative disorder?

EBV

What type of lymphadenopathy suggests systemic disease?

Generalized

Which autoimmune disease is commonly associated with lymphopenia?

Systemic lupus erythematosus

How do corticosteroids cause lymphopenia?

Redistribution and apoptosis of lymphocytes

What is a common presentation of reactive lymphadenopathy?

Tender, mobile nodes with signs of infection

What is the typical architecture of a reactive lymph node?

Preserved

What is the architecture of a lymphoma-involved lymph node?

Disrupted

What is the most common NHL subtype in adults?

Diffuse large B-cell lymphoma

What is the function of BCL2 in follicular lymphoma?

Inhibits apoptosis

What is the translocation in mantle cell lymphoma?

t(11;14)