Workshop Case #2 (H 331/ 09)

Age 24 years

Sex male

Localization lymph node dorsal musc.

sternocleidomastoideus

Clinical data NHL?

follicle

follicle HE ; 5X

Giemsa X40

CD30 x20

KI 67

Ki-67 CD20 CD3

CD 30 KI 67 CD 20

Lambda Kappa

WÜ – case H3403-08; Fig. : 6

Microscopic findings

Preserved lymph node structure. Inconspicuous

primary and some secondary follicles with germinal

centers. Diffuse hyperplasia of paracortical pulp area

with massive increase of blast cells.

Blast cells are CD30 + , CD 20 and CD79a negative.

Areas infiltrated by these blasts are illdefined mostly

around small vessels and sinus. Very high

proliferative activity .Immunoglobulin light chains are

polytypic.

Molecular data

IgH FR3a and –FR2a PCR : polyclonal

TCR-gamma PCR : polyclonal

Differential diagnosis

Partial infiltration of l.n. by NHL (e.g.

ALCL)?

If reactive:

Functional interpretation of findings?

Etiopathogenesis?

Donkey

anti Mouse

Donkey

anti Rabbit

m K

i67

r CD

3

Goat

anti FITC

Donkey

anti Goat

m C

D79a

• CD79a ICSAT KI67

Germinal center reaction Extrafollicular reaction

Ki67 CD79a IRF-4

• Bild intrafollicular

icsat+ cells are

CD79a+ IgL+

super 15310_01

Chef spezial Mantel,

Keim,

Aussen3_Ov4Ausse

n CD79a gruen, Igl

rot, Icsat blau.jpg

CD79a IgL IRF-4

Germinal center reaction Extrafollicular reaction

H1317/01

CD79a

IgL

CD138 germinal center reaction

IgG +

CD27 +

CD138 +

IgM +

CD27 –

CD138 –

Extrafollicular pathways of the B-cell activation

„short - lived“

„long - lived“

B-cell development in lymph nodes

CD20

CD79a PAX5

CD10

BCL6

BCL2 PU1

IRF-4

CD138

IgG

Ki67

CD27

BLIMP-1

memory cell

reactive memory

plasma cell

protective memory

Etiopathogenesis

Polyclonal activation of prefollicular ( naive) B

cells due to T cell independant antigens or

superantigen ( Bacterial polysaccharides or

capsule components).

Polyclonal activation of memory B cells

(anamnestic response, Virus, immune

deficiency,BMTx ?)

Hyperimmune reaction:

Marked extrafollicular activation of lymph

node

Diagnosis Case #3

Serology of Antibody Response

IgM

IgG

time

Serum level

Antigen challenge Antigen booster

9113/01

• EFH 15310

Germinal center reaction Extrafollicular reaction

Extrafollicular activation Medullary cords Germinal center

Memory cell

Reactive Memory

Antigen Antigen

Plasma cell

Protektive Memory

CD20

CD79a PAX5

CD10

BCL6

BCL2 PU1

IRF-4

CD138

IgL

Ki67

CD27

CD30

BLIMP-1

Literature

Brighenti A, Andrulis M, Geissinger E et al. (2005) Extrafollicular

proliferation of B cells in the absence of follicular hyperplasia: a distinct

reaction pattern in lymph nodes correlated with primary or recall type

responses. Histopathology 47:90-100

Liu YJ, Zhang J, Lane PJ, Chan EY, MacLennan IC. Sites of specific B

cell activation in primary and secondary responses to T cell-dependent

and T cell-independent antigens. Eur J Immunol. 1991;21(12):2951-

2962.

Plasma-

cell

Proliferation

Affinity maturation by somatic

hypermutation and selection

Class switch

B Cell

Germinal Center

CD27-

IgM+

CD27+

IgM-

IgG/A+