A
S t u d y
o f
the
E m p h a s i s
N a t u r e
o n
o f
"Hairy"
E n z y m a t i c
Cells,
with
M a r k e r s
L. A. ROZENSZAJN, P H . D . , A. GUTMAN, M.D., J. RADNAY, M . S C ,
E. B E N DAVID, B . S C , AND D. S H O H A M , P H . D .
From the Hematologic Laboratories, Department of Internal Medicine C, Meir Hospital, Kfar Sa
and Department of Life Sciences, Bar-llan University, Ramat-Gan, Israel
ABSTRACT
Rozenszajn, L. A., Gutman, A., Radnay, J., Ben David, E., and Shoham,
D.: A study of the nature of "hairy" cells, with emphasis on enzymatic
markers. Am J Clin Pathol 66: 4 3 2 - 4 4 1 , 1976. Studies of peripheral
blood, bone marrow, and spleen cells from three patients with hairy-cell
leukemia were performed. Two of the three patients had well-organized
cytoplasmic, ribosome-lamellar inclusions in their leukemic cells. Blast
transformation and 3 H-thymidine incorporation of lymphocytes seemed
to fall within normal ranges when the findings were related to the absolute
numbers of lymphocytes. T h e enzymatic markers demonstrated in hairy
cells—strong acid phosphatase activity in endoplasmic reticulum and
lysosomes, marked a-naphthyl acetate esterase reaction, and weak /3glucuronidase activity—as well as their phagocytosis of latex particles,
indicate a common origin with monocytes or histiocytes. No decisive results were obtained by immunofluorescence. Evaluation of the significance
of the formation by hairy cells of mouse erythrocyte rosettes, as well as
the presence of the typical hair-like projections, may require additional
knowledge concerning the membrane of these cells. (Key words: Leukemia;
Hairy-cell leukemia; Leukemic reticuloendotheliosis; cytochemistry,
ultrastructure; Phagocytosis: Cell surface markers; Lymphocyte culture.)
W E have had the opportunity to study three nuclear cell, found in bone marrow, tissues,
patients with hairy-cell leukemia, a disease and peripheral blood, that resembles a
that accounts for approximately 2% of lymphocyte but also has cytoplasmic proall leukemias. 4 Clinically, the disease is jections suggestive of reticulum cells.•'•I3'lil-characterized by chronic course, spleno- 20,33
megaly, anemia, and thrombocytopenia.
Controversial opinions have been exMorphologic features distinguishing this pressed concerning the nature of these
disease from other forms of leukemia are hairy cells: a lymphocytic origin2-"-9,11,14-24-30
connected with proliferation of a mono- or a close relationship to monocyteshistiocytes17-37 has been advocated. On the
Received August 20, 1975; received revised manu- basis of scanning electron microscopy,
script October 20, 1975; accepted for publication "hairy" cells were described as resembling
October 20, 1975.
31
Supported in part by a grant from the Research B lymphocytes12 or having the appearance
Committee, Bar-llan University.
of monocytes.
Address reprint requests to Professor Rozenszajn:
"Hairy" cells have been shown to contain
The Clinical Laboratories, Meir Hospital, Kfar
Saba, Israel.
a tartrate-resistant isozyme of acid phos432
August 1976
433
NATURE OF "HAIRY" CELLS
Table 1. Summary of Clinical and Laboratory Findings in Three Patients
Patient 1
Patient 2
Patient 3
Age (years)/sex
41/F
64/M
51/M
Presenting symptoms
4 weeks: protracted infection, progressive
headache, fatigue,
weakness, pallor,
dyspnea on exertion
4 weeks: abdominal
pain, general weakness, fatigue, pallor
8 weeks: abdominal
pain, fatigue, weakness, pallor; 3 weeks:
fever, weight loss
Hepatomegaly*
6 cm
3 cm
5 cm
Splenomegaly*
8 cm
4 cm
12 cm
Splenic aspiration
Mostly hairy cells
Mostly hairy cells
Liver biopsy
Sinusoids, portal areas
+++
+
Sinusoids, portal areas
+++
0
N.D.t
Sinusoids, portal areas
+++
+
Small submandibular
and axillary
Dry tap
None
Small axillary and
inguinal
Normocellular, 50%
hairy cells
Hypercellular, predominantly hairy
cells
N.D.
Not adequate, mostly
hairy cells
N.D.
Leukemic infiltration
Lymphadenopathy
Bone marrow aspirate
Bone marrow biopsy
Peripheral blood
Leukocytes, x 103/cu mm
Hairy cells, %
Lymphocytes, %
Neutrophils, %
Nucleated erythrocytes/
100 leukocytes
Hemoglobin, g/dl
(/a.mol/1)
Hematocrit, %
Reticulocytes, %
Platelets, x 10'Vcu mm
3.2-5.3
21-24
7.2-15
55-85
45-52
6.4-9.2
32-50
20-24
13-22
1-2
19-25
no
1-5
6.7-8.8
(1.0385-1.364)
12.1-13.0
(1.8755-2.015)
22.0-26.3
(.22-26.3)
1.2
(.012)
50-160
33.1-38.6
(.331-.386)
0.4-1.6
(.004-.016)
49-71
14-20
4-18
8.7-10.2
(1.3485-1.581)
26.3-33.3
0263-.333)
1.8-6.6
(.018-.066)
28-50
* Palpation below the costal margin.
t Not done.
phatase, a property almost exclusively
limited to reticulum cells.38
Esterase activity regularly present in
normal monocytes 27 was also found in
"hairy" cells.32 On the other hand, "hairy"
cells have been reported to possess some
properties of B lymphocytes, such as presence of surface immunoglobulins and formation of rosettes with mouse erythro-
I
cytes. 2.6.7,9.H,24 By contrast, their monocytic-histiocytic nature is suggested by
their ability for phagocytosis of bacteria
and latex particles. 10
Since diagnosis of hairy-cell leukemia
has important therapeutic and prognostic
implications, studies have been performed
in order to define more precisely the nature
of these mononuclear cells.
434
ROZENSZAJN £T/IL.
Case Reports
T h e essential features of the three cases
studied are summarized in Table 1. Results of additional tests (blood chemistry,
urinalysis and immunoglobulins) were
within normal limits.
Material and Methods
T h e material studied consisted of peripheral blood, buffy coat, and bone
marrow in all three cases, and of splenic
cells in two of the three.
Morphologic Studies. Smears of peripheral
blood, buffy coat, bone marrow, and
splenic cells were stained with May-Grunwald Giemsa (MGG). Phase-contrast microscopy was used to examine fresh preparations.
Electron Microscopy. Examinations were
performed on buffy coat obtained from
heparinized peripheral blood (250 IU/10
ml). Bone marrow and spleen cells were
fixed in 2.5% glutaraldehyde in 0.2 M
Na-cacodylate-HCl buffer (pH 7.2) containing 7% sucrose, and kept at 4 C for 2
hours. T h e samples were washed with N a cacodylate, postfixed in 1% O s 0 4 in cacodylate-HCl buffer, dehydrated in graded
ethanols followed by propylene oxide,
and embedded in Epon 812 as described
by Luft.21 Sections were made with an
LKB ultratome, stained with uranyl acetate
and lead citrate, and examined with a
Philips 300 electron microscope.
Cytochemical Studies. Unstained films of
capillary peripheral blood, bone marrow,
and spleen were stained for esterase activity using alpha-naphthyl acetate and
naphthol AS-D chloroacetate as substrates, 27 for peroxidase for general diagnosis, 23 and for azo-dye coupling methods
for alkaline and acid phosphatase with
and without L( + )-tartaric acid (0.05 M) in
the staining solutions. 18 ' 28 T h e periodic
acid-Schiff reaction was obtained before
and after ptyalin digestion. 1 " Glycogen
content and acid and alkaline phosphatases
A.J.C.P.—Vol.66
were estimated semiquantitatively. 28 T h e
enzymatic activity of /3-glucuronidase was
demonstrated by an azo-dye coupling
method using fast garnet GBC. The technic
was similar to that described for determination of acid phosphatase activity28 with
naphthol AS-BI /3-D-glucuronide serving
as substrate.
Ultrastructural Cytochemistry. In order to
demonstrate acid phosphatase activity,
buffy coat leukocytes and spleen cells were
fixed in 1% glutaraldehyde in 0.2 M N a cacodylate-HCl buffer (pH 7.2) for 15
minutes at 4 C. T h e cells were then washed
three times with the same cacodylate buffer.
T h e fixed cells were suspended in
Gomori incubation medium 26 and maintained at 37 C at pH 4.8 for two hours.
After incubation the cells were washed
three times in Na-cacodylate buffer and
postfixed by 1% O s 0 4 in cacodylate buffer
for one hour, dehydrated, and embedded
in Epon 812. 21 Thin sections were cut with
a diamond knife and double-staining with
uranyl acetate and lead citrate was performed after testing for the presence of
products of enzymatic activity on unstained sections.
As a control for specificity of the staining method, fixed cells were incubated
with the incubation solution lacking the
substrate /3-glycerophosphate.
Phagocytic Activity. T h e test was performed by incubating suspensions of peripheral blood leukocytes with latex particles (0.81 /mi, Difco).
Twenty-milliliter samples of venous
blood were obtained by means of disposable plastic syringes containing 2 5 0 500 IU heparin. The erythrocytes were
sedimented in the inverted syringe for 60
to 90 min at 37 C. The supernatant plasma
containing leukocytes was centrifuged for
15 min at 140 x g. T h e sedimented cells
were washed three times in saline solution and resuspended to a concentration
of 0.8 x 106/ml. A mixture consisting of
0.5 ml pooled human serum, 0.1 ml latex,
August 1976
435
NATURE OF "HAIRY" CELLS
rmni ~~"T"
•***'
",
i
FIG. 1. Phase-contrast microscopy of
fine hair-like cytoplasmic projections
from the surfaces of abnormal cells. \
Peripheral blood (buffy coat). x400.
I
»~*^ *• «• V
0.5 ml saline solution, and 0.3 ml cell
suspension was incubated at 37 C for two
to three hours, or at 4 C for 20 hours.
Phagocytic activity was assayed by phasecontrast microscopy.
Leukocytic Isozymes. Electrophoretic study
for acid phosphatase isozyme and tartrateresistant acid phosphatase isozyme was
performed by using disk electrophoresis
on polyacrylamide-gel columns.
T h e specimens were stained with and
without L(+)-tartaric acid in the incubation solutions. 38
Culture Method. Heparinized peripheral
blood was allowed to sediment for an
appropriate time, and the leukocyte-rich
plasma was separated. Cultures were performed by the method of Moorhead, 22
using Bactophytohemagglutinin M (PHA)
(Difco) to induce transformation of the
lymphocytes.
Additional leukocyte cultures were
made after glass-adherent cells were removed from the suspension. 25
The morphology of the cultured cells
was examined in smears stained with MGG
after 72 hr of culture, and the percentage
of transformed lymphocytes, i.e., large cells
with basophilic cytoplasm, was determined
by counting 1,000 cells in each smear.
a
H Incorporation. 3 H-Thymidine, 0.1 fxC\l
ml, was added to the culture 20 hr after
its initiation.29
Cell Surface Markers. Tests were done
for spontaneous E-rosette formation with
sheep erythrocytes (SRBC) (T cells),36 and
for rosette formation with mouse erythrocytes of strain C57B1 (MRBC) (B cells)35;
lymphocytes were tested for the presence
of membrane-associated immunoglobulin
(B cells).1
Binding of Concanavalin A-Fluorescein
Isothiocyanate (Con A-FITC). Samples of peripheral blood (20 ml) were collected in
disposable heparinized syringes. T h e
supernatant plasma containing leukocytes
was decanted and centrifuged; the cell
button was resuspended in phosphatebuffered saline solution to a final concentration of 3 - 5 x 10 6 cells/ml. T o 0.5 ml of
cell suspension, 1 /A1 of Con A-FITC (14
mg/ml, Miles/Yedda, Rechovot) was added,
and the mixture was incubated for 5 min
at37C.
T h e samples were examined for fluorescence with a Zeiss UV Photomicroscope,
vertical illuminator.
Results
Phase-contrast microscopy demonstrated
the presence of "hairy" cells, characterized
by an irregular flagellated appearance and
pseudopodic extensions of the cytoplasmic
border.
T h e nuclei, eccentric in position in
numerous cells, were oval or round, with
prominent nuclear membranes. In a few
cells nucleoli were visible (Fig. 1).
436
ROZENSZAJN£T/fL.
AJ.C.P.—Vol.
'-: '. •»•% ' 4 * ' s i r
66
~'*»
Fie. 2. Electron micrograph, illustrating the characteristic morphology of hairy cells, manifested by
many long and short cytoplasmic extensions projecting from the surfaces of the cells. N = nucleus;
G = Golgi apparatus; L = lysosonies; M = mitochondria; ER = short and long profiles of endoplasmic
reticulum; V = vacuoles, x 12,000.
Light Microscopy. T h e "hairy" cells were
large compared with lymphocytes. The
cytoplasm showed characteristic flagellalike projections, stained grayish-blue, and
contained azurophilic granules.
Electron Microscopy. "Hairy" cells contained numerous irregular, fine, long and
short cytoplasmic projections emerging
from the cell periphery. The nuclei were
oval and slighdy indented. Marginal to the
nuclear membrane a moderate amount of
heterochromatin was present, and nucleoli
were visible in some cells. T h e cytoplasm
contained numerous round or oval mitochondria, small vesicles, some lysosome
granules, and ribosomes, as well as short
and long profiles of rough endoplasmic
reticulum (Fig. 2). Thrombophagocytosis
was observed in one peripheral blood cell.
Golgi complexes were seen in only a few
cells and appeared to be of moderate size.
Samples from two of the three patients
showed well-organized cytoplasmic ribosome-lamellar inclusions, appearing in
cross sections as granular concentric circles
showing ribosomes between the lamellar
structures. In oblique sections they appeared as elliptical profiles, and in longitudinal sections as multiple parallel
lamellae (Fig. 3).
Leukocytic Acid Phosphate Isozymes. A
tartrate-resistant enzymatic band representing isozyme 5 was found in the two
samples in which the test was performed
(Table 2).
Acid Phosphatase. Azo-dye staining of
August 1976
437
NATURE OF "HAIRY" CELLS
FIG. 3. Electron micrograph of hairy cell from peripheral blood containing three cytoplasmic inclusions: two in oblique sections appearing as elliptical profiles, and one in longiiudinal section as
multiple parallel lamellae. X 17,000.
"hairy" cells revealed strong positive reacdons. From 90 to 100% of the cells showed
enzymatic activity. In the presence of
L(+)-tartaric acid in the incubation solu-
tion, the enzymatic reaction was slightly or
markedly inhibited.
Peroxidase. No enzymatic activity was
demonstrated in the leukemic cells.
Table 2. Cytochemical Findings Obtained in Three Patients with Hairy-cell Leukemia
Haii) Cells
Acid phosphatase
Acid phosphatase L(+)-tartrate
Peroxidase
/3-Glucuronidase
Esterase activity:
a-Naphthyl acetate
Naphthol AS-D chloroacetate
Alkaline phosphatase
P.A.S.
Neutrophilic
Granulocytes
Lymphocytes
Monocytes
Blood
Spleen
2+
4+
3+
1+
3+
3+
4+
+
1+
3+/4 +
I+/2 +
1+
3+
4+
2+
I+/2 +
3+
1+
2+
1+
2+
1+
1+
438
A.J.C.P.—Vol.
ROZENSZAJN ET AL.
'o'<.
66
-.?
•• -' '"-•• *;*" "'••" • ^ • • • • ' K * V ' - v ' i ^ s s s ^ - i v ' -
>••'••
If
%:Mr
¥*:•'*
•ts>,
!•
'
-USB/'
*
•" '*?V-••'•v"'.'-.:'- "V;>' : . r T ; ' / '?*:'' '
' :''"
'. . .•••••'fS'.
»i(rT'.
y •••
Fie. 4. Characteristic hairy cell from peripheral blood (unstained section) stained by enzymatic
reaction product, acid phosphatase-/? glycerophosphate. The sites of enzymatic activity are indicated by
deposits of lead phosphate. Note enzymatic reaction in profiles of endoplasmic reticulum and lysosome (mrow). x 11,000.
^-Glucuronidase. Enzymatic activity was
strong in small lymphocytes, expressed as
granules and clumps of brown color,
"Hairy" cells showed weak enzymatic ac-
tivity, expressed by fine granules scattered
throughout the cytoplasm, and present in
greater concentration in the cytoplasmic
projections.
Table 3. Blast-cell Transformation, 3 H-Thymidine Incorporation, and
Surface Markers in Hairy-cell Leukemia
Patient 1
Patient 2
Patient 3
Leukocytes
(per
cu mm
Blood)
Hairy
Cells
(%)
5,300
8,700
9,800
21
50
85
* Control cptn = fi2.500.
t SRBC = sheep erythnx'ytes.
t MRBC = mouse erythrocytes.
Lymphocytes
(%)
Lymphocytes
Blast-like
Transformation
(%)
^-Thymidine Incorporation
cpm/106
Cells*
E
Rosettes
(SRBCt)
(%)
B
Rosettes
(MRBCt)
(%)
Immunofluorescence
(%)
52
24
14
90
30
20
47,500
17,000
14,500
50
20
12
4-5
20
50
40
50
90 or more
August 1976
NATURE OF "HAIRY" CELLS
Esterase Activity with a-Naphthyl Acetate
Substrate. Strong esterase activity was
demonstrated in numerous "hairy" cells.
Esterase Activity with Naphthol AS-D Chloroacetate Substrate. No enzymatic activity
was demonstrated in the leukemic cells.
Alkaline Phosphatase. Increased enzymatic
activity was demonstrated in neutrophil
granulocytes. "Hairy" cells did not stain.
PAS Reaction. A few fine cytoplasmic red
granules and diffuse reaction were found
in some leukemic cells.
Acid Phosphatase (Electron Microscopy).
Enzymatic activity was observed to be
localized in small and large profiles of the
endoplasmic reticulum, some vesicles, and
lysosomes (Fig. 4).
Phagocytosis of Latex Particles. As studied
under the phase microscope, latex particles
appeared to be phagocytized in more than
50% of the "hairy" cells after incubation at
37 C; lesser phagocytic uptake occurred
after incubation at 4 C.
Lymphocyte Transformation and 3H incorporation. T h e percentage of transformed
lymphocytes and incorporation of :i Hthymidine appeared to be less in the
presence of a high percentage of leukemic
cells in the peripheral blood (Table 3).
Transformation of lymphocytes and
:i
H-incorporation were within the normal
ranges in the sample from Patient 1,
••if.
#5-
t
F I G . 5. Phase-contrast microscopy, illustrating
rosette f o r m e d bv hairy cell with mouse erythrocytes X'100.
439
F I G . 6. H a i r y cell, after treatment with Con A - F I T C .
e m i t t i n g fluorescence concentrated in perinuclear
zone.
who had a low percentage of "hairy"
cells, whereas abnormally low values
were found in Patient 2 and Patient 3,
who had high percentages of leukemic
cells.
Results were essentially similar when
glass-adherent cells were removed from the
total leukocyte suspension before they were
cultured and assayed.
Rosette Formation and Presence of Immunoglobulin. Spontaneous E-rosette formation
with SRBC (T cells) and rosette-forming
ability with MRBC (B cells) (Fig. 5) were
almost normal in the blood of Patient 1,
who had a low percentage of leukemic
cells. Samples from the other two patients showed 20 and 50% MRBC rosettes
(Table 3).
When characteristic irregular flagellated
projections of the cytoplasm could be
recognized u n d e r phase microscopy,
examination of MRBC rosettes showed
that erythrocytes were not attached to the
entire cell circumference (Fig. 5). A
characteristic immunofluorescence was
observed in some lymphocytes.
In typical "hairy" cells, green fluorescence was observed in the cytoplasmic
perinuclear zone.
Con A-FITC.
A marked light green
fluorescence was emitted by the cytoplasm
of "hairy" cells. T h e most intensive fluores-
440
ROZENSZAJN£T/fZ..
A.J.C.P.—Vol.
66
cent area was the perinuclear zone. In of "hairy" cells8 may indicate an abnormal
gene expression in the pathologic cells,
a few lymphocytes caps were seen.
T h e fluorescence of the "hairy" cells manifested by immunoglobulin synthesis.
T h e percentage of transformed cells was
may be due to the prominent pinocytotic
not significantly increased by removing
ability of the leukemic cells (Fig. 6).
glass-adherent cells prior to culture. This
suggests that "hairy" cells do not possess a
Discussion
strong ability to adhere to glass surfaces.
T h e presence of lysosomal enzymes,
A similar deviation from the behavior of
such as esterases, acid phosphatase, and
normal monocytes is shown by the fact
peroxidases, serves as a useful criterion
that "hairy" cells do not convert to macrofor identification of the cell series, even in
phages in liquid culture media in presthe early developmental stages of normal
ence of PHA. These observations may
leukocytes. Based on this assumption,
indicate an incomplete differentiation of
abnormal leukocytes in peripheral blood
the leukemic cells, inasmuch as they have
and/or bone marrow have been differsome, but not all, properties of monocytes.
entiated according to cytochemical propT h e phagocytic activity, together with
erties, as manifested by characteristic
15,27,34
the
cytoplasmic enzymatic markers, speaks
enzymatic markers.
Lysosomal enfor
a common origin of "hairy" cells and
zymatic activity may also be found in leumonocytes;
on the other hand, spontakemic cells, which did not show any clearneous
MRBC
rosette formation indicates
cut morphologic differentiation toward a
that
"hairy"
cells
are related to B lymphospecific hemopoietic series.
cytes.7
According to the results of the present
T h e significance of the formation of
study, the enzymatic markers demonMRBC rosettes with "hairy" cells cannot
strated in "hairy" cells indicate that they
be fully evaluated without additional
may have a common origin with monoknowledge concerning the membrane of
cytes or histiocytes. This assumption is
these cells, including the presence of the
supported by the finding of strong acid
hairlike projections.
phosphatase activity in "hairy" cells,
Cytoplasmic lamellar inclusions were
particularly localized in the endoplasmic
observed in the bloods of two of the three
reticulum, and the few lysosomes present.
patients examined, and they did not seem
In addition, the strong a-naphthyl aceto be correlated with the clinical condition
tate esterase reaction within the leukemic
of the leukemia. Similar tubular cytocells was similar to that observed in normal
plasmic structures have also been observed
27,34
and leukemic monocytes,
whereas
in other malignant hematologic dislymphocytes showed only weak enzymatic
eases, 3,5 ' 39 limiting the diagnostic value of
staining.
these ultrastructural inclusions.
A marker common to both "hairy" cell
and B lymphocyte was found in the form
Acknowledgments. Mr. Jacov Goldman and Miss Dina
of MRBC rosettes (Fig. 5). On the other Joseph provided skillful technical assistance.
hand, we failed to obtain decisive results
from assays of immunofluorescence. It
References
seems to us that the fluorescence appear1. Aisenberg AC, Bloch KJ: Immunoglobulins on
ing in both immunofluorescence and Con
the surface of neoplastic lymphocytes. N
Engl J Med 287:272-276, 1972
A-FITC assays of "hairy" cells reflects
2. Aisenberg AC, Bloch KJ, Long JC: Cell-surface
their pinocytotic ability, and that it does
immunoglobulin in chronic lymphocytic
leukemia and allied disorders. Am J Med
not conclusively prove interaction with
55:184-191, 1974
membrane markers.
3. Anday GJ, Goodman JR, Tishkoff GH: An
Studies reporting immunofluorescence
unusual cytoplasmic ribosomal structure in
August 1976
NATURE OF "HAIRY" CELLS
pathologic lymphocytes. Blood 41:439-449,
1973
4. Bouroncle BA, Wiseman BK, Doan CA:
Leukemic reticuloendotheliosis. Blood 13:
609-630, 1958.
5. Brunning RD, Parkin BS: Ribosome-lamella
complexes in neoplastic hematopoietic cells.
Am J Pathol 79:565-572, 1975
6. Burns CP, Maca RD, Hoak JC: Biochemical,
morphological and immunological observations of leukemic reticuloendotheliosis.
Cancer Res 33:1615-1621, 1973
7. Catovsky D, Papamichail M, Okos A, et al:
Formation of mouse red cell rosettes by
"hairy" cells. Biomedicine 23:81-84, 1975
8. Catovsky D, Pettit JE, Galetto J, et al: The Blymphocyte nature of the hairy cell oi
leukemic reticuloendotheliosis. Br J Haematol
26:29-37, 1974
9. Catovsky D, Pettit JE, Galton DAG, et al:
Leukaeniic reticuloendotheliosis ("Hairy" cell
leukemia): A distinct clinicopathological entity.
Br J Haematol 26:9-27, 1974
10. Daniel MT, Flandrin G: Fine structure of
abnormal cells in hairy cell (tricholeukocytic)
leukaemia, with special reference to their
in vitro phagocytic capacity. Lab Invest 30:
1-8, 1974
11. Ghadially FN, Skinnider LF: Ultrastructure of
hairy cell leukemia. Cancer 29:444-452, 1972
12. Golomb HM, Braylon R, Polliack A: "Hairy"
cell leukaemia (leukaeniic reticuloendotheliosis): A scanning electron microscopic
study of eight cases. Br J Haematol 29:
455-460, 1975
13. Gosselin GR, Hanlon DG, Pease GL: Leukemic
reticuloendotheliosis. Can Med Assoc J 74:
886-889, 1956
14. Haak HL, de Man JCH, Hijmans W. et al:
Further evidence for the lymphocytic nature
of leukaeniic reticuloendotheliosis (hairy-cell
leukemia). Br J Haematol 27:31-38, 1974
15. Hayhoe FGJ, Quaglino D, Doll R: The cytology
and cytochemistry of acute leukaemias. Spec
Rep Ser Med Res Council (Loud), 1964
16. Hayhoe FGJ, Quaglino D, Flemans RJ: Consecutive use of Romanowsky and periodicacid-Schiff technique in study of blood and
bone marrow cells. Br J Haematol 6:2325, 1960
17. Jaffe ES, Shevach EM, Frank MM, et al: Leukemic reticuloendotheliosis: Presence of a
receptor for cytophilic antibody. Am J Med
57:108-114, 1974
18. Kaplovv LS: A histochemical procedure for
localizing and evaluating leukocyte alkaline
phosphatase activity in smears of blood and
marrow. Blood 10:1023-1029, 1955
19. Katayama I, Li CY, Yam LT: Ultrastructural
characteristics of the "hairy" cell of leukemic
reticuloendotheliosis. Am J Pathol 67:361370, 1972
20. Lee SL, Rosner R, Rosenthal N, et al:
Reticulum cell leukemia. Clinical and
hematologic entity. NY State J Med 68:422429, 1969
21. Luft JH: Improvements in epoxy resin embedding methods. J Biophys Biochem Cytol
9:409-414, 1961
441
22. Moorhead PS, Nowell PC, Mellman VVY, et al:
Chromosome preparations of leukocytes
cultured from human peripheral blood.
Exp Cell Res. 20:613, 1960
23. Osgood E, Ash worth CM: In Diagnostic Laboratory Hematology. Second edition. Edited by
GE Cartwright. New York, Grime and Stralton, 1958, p 91
24. Preud'homme JL, Seligman M: Surface bound
immunoglobulin as a cell marker in human
lymphoproliferative diseases. Blood 40:
777-794, 1972
25. Rabinovich Y: Separation of lymphocytes on
glass columns, including tissue culture observations. Blood 23:81 1-828, 1964
26. Rozenszajn L, Efrati P: Cytochemical and phasecontrast observations on Gaucher cells. Acta
Haematol 25:43-48, 1961
27. Rozenszajn L, Leibovich M, Slioham D, et al:
The esterase activity in megaloblasts, leukemic
and normal haemopoietic cells. Br J Haematol
14:605-610, 1968
28. Rozenszajn L, Marshak G, Efrati P: Acid phosphatase activity in normal human blood and
bone marrow cells as demonstrated by the azo
dye method. Acta Haematol 30:310-316,
1963
29. Rozenszajn L, RadnayJ: The effect of methotrexate on transformation and mitosis of normal
human blood lymphocytes in vitro. Blood 43:
401-409, 1974
30. Rubin AD, Douglas SD, Chessin JN, et al:
Chronic reticulo-lymphocytic leukemia. Reclassification of "leukemic reticuloendotheliosis" through functional characterization
of the circulating mononuclear cells. Am J
Med 47:149-162, 1969
31. Schnitzer B, Hammack WJ: B-lymphocyte nature
of hairy cells in hairy-cell leukemia. Lancet
2:649, 1974
32. Schnitzer B, Kass L: Hairy-cell leukemia: A
clinicopathologicand ultrastructural study. Am
J Clin Pathol 61:176-187, 1974
33. Schrek R, Donnelly WJ: "Hairy" cells in blood in
lymphoreticular neoplastic disease and "flagellated" cells of normal lymph nodes. Blood 27:
199-221, 1966
34. Shaw MT, Nordquist RE: "Pure" monocytic or
histiomonocytic leukemia: A revised concept.
Cancer 35:208-214, 1975
35. Stathopoulos G, Elliott E: Formation of mouse or
sheep red-blood cell rosettes by lymphocytes
from normal and leukemic individuals. Lancet
1:600-601, 1974
36. Wybran J, Chantler S, Fudenberg HH: Isolation of normal T cells in chronic lymphatic
leukemia. Lancet 1:126-129, 1973
37. Yam LT, Castoldi GL, Garvey MB, et al:
Functional cytogenetic and cytochemical study
of the leukemic reticulum cells. Blood 32:90101, 1968
38. Yam LT, Li CY, Lam KW: Tartrate-resistant
acid phosphatase isoenzyme in the reticulum
cells of leukemic reticuloendotheliosis. N
Engl J Med 284:357-360, 1971
39. Zucker-Franklin D: Virus-like particles in the
lymphocytes of a patient with chronic lymphocyte leukemia. Blood 21:509-512, 1963