Cytochemical study of thymocytes and T lymphocytes

Partial protective effects of melatonin on cadmium-induced changes in hematological characteristics in rats

We investigated the effects of melatonin (Mlt) on hematological characteristics to determine the percentage of alpha-naphthyl acetate esterase (ANAE) positive lymphocytes in rats chronically exposed to cadmium (Cd). We used four groups of male rats: control (C), melatonin (Mlt), cadmium (Cd) and Cd + Mlt (CdMlt). Blood samples were obtained to assess the erythrocytes (RBC), leukocytes (WBC), platelets (PLT), hemoglobin (HGB), hematocrit (HCT), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV) as well as alpha-naphthyl acetate esterase (ANAE) positive lymphocytes. We found that the number of WBC increased in the Cd group compared to the other three experimental groups. Low MCV and MCHC values caused by Cd were ameliorated by Mlt treatment in the CdMlt group. We found no significant change in the RBC, HGB, MCH, PLT and HCT values among the experimental groups. Mlt treatment also increased the percentage of ANAE positive lymphocytes. Mlt partially protects some hematological characteristics in cases of chronic Cd toxicity.

Effects of long term oral acrylamide administration on alpha naphthyl acetate esterase and acid phosphatase activities in the peripheral blood lymphocytes of rats

Acrylamide is an important industrial chemical; it also is formed in starch-rich foodstuffs during baking, frying and roasting. Most acrylamide exposure occurs by ingestion of processed foods. We investigated possible immunotoxic effects of extended administration of low doses of acrylamide in rats. To do this, we measured alpha-naphthyl acetate esterase (ANAE) and acid phosphatase (ACP-ase) activities in peripheral blood lymphocytes. Male and female weanling Wistar rats were administered 2 or 5 mg acrylamide/kg/day in drinking water for 90 days. Peripheral blood was sampled at the end of the administration period. We found ANAE staining in eosinophils and T-lymphocytes, but not in monocytes, platelets, B-lymphocytes and neutrophils. ACP-ase was found in B-lymphocytes. We found a significant reduction of the ratio of ANAE:ACP-ase in lymphocytes of the experimental animals compared to controls. We found no statistically significant differences between the doses or sexes. We found that acrylamide ingested in processed foods might affect the immune system adversely by decreasing the population of mature T- and B-lymphocytes.

Protective effect of quercetin on some hematological parameters in rats exposed to cadmium

We investigated the effects of quercetin (Q) on some hematological parameters and determined the percentage of alpha-naphthyl acetate esterase (ANAE) positive lymphocytes in rats that had been exposed to cadmium (Cd). Thirty male Wistar albino rats were divided into four groups: control (C), quercetin (Q), cadmium (Cd) and Q + Cd (CdQ). Blood samples were taken to assess erythrocytes (RBC), leukocytes (WBC), hemoglobin levels (Hb), hematocrit values (Hct), platelets (PLT), alpha-naphthyl acetate esterase (ANAE) positive lymphocytes. RBC, Hb, Hct; the number of PLT significantly decreased in the Cd group. To the contrary, these parameters were increased significantly in the CdQ group compared to the Cd group. Although we found a significant increase in total WBC count and neutrophil percentage, the number of lymphocytes decreased in the Cd group compared to the other three groups. Also, the percentage of peripheral blood ANAE positive lymphocytes decreased significantly in the Cd group (p < 0.05). Q exhibits positive effects on some hematological characteristics and the percentage of ANAE positive lymphocyte in cases of acute CD toxicity.

A study of peripheral blood in hedgehogs in Turkey

The aim of this study was to determine diameters of blood cells, differential counts of peripheral blood leukocytes, alpha-naphthyl acetate esterase (ANAE), acid phosphatase (ACP-ase) activity of some leukocyte types, and enzymatic positivity percentages of peripheral blood lymphocytes in two hedgehogs species, Hemiechinus auritus, the long-eared hedgehog, and Erinaceus concolor, the southern white-breasted hedgehog. Air-dried peripheral blood smears were stained with May-Grünwald-Giemsa stain. ANAE and ACP-ase were stained in glutaraldehyde-acetone-fixed smears. ANAE-positive lymphocytes displayed a dot-like positivity pattern characterized with 1-5 reddish brown cytoplasmic granules, whereas ACP-ase positive lymphocytes displayed a dot-like positivity pattern characterized with 1-3 pinkish cytoplasmic granules. Monocytes gave a diffuse and strong reaction while neutrophils displayed a weak positive reaction for ANAE and ACP-ase. No difference was observed in mean diameters of peripheral blood cells of these species. It was found that lymphocytes made up the majority (64.3% and 65.5%) of leukocytes, followed by neutrophils (23.9% and 23.3%), eosinophils (9.0% and 7.6%), monocytes (1.8% and 2.3%), and basophils (1.0% and 1.3%) in H. auritus and E. concolor, respectively. Mean ANAE positivity oflymphocytes was 36.6% and 51.3% and ACP-ase positivity was 32.1% and 37.5% for H. auritus and E. concolor, respectively. The ANAE positivity of lymphocytes in E. concolor was significantly (P < 0.05) higher than that of H. auritus.

Lactic acid bacteria in the prevention of pneumococcal respiratory infection: future opportunities and challenges

Lactic acid bacteria (LAB) are technologically and commercially important and have various beneficial effects on human health. Several studies have demonstrated that certain LAB strains can exert their beneficial effect on the host through their immunomudulatory activity. Although most research concerning LAB-mediated enhanced immune protection is focused on gastrointestinal tract pathogens, recent studies have centered on whether these immunobiotics might sufficiently stimulate the common mucosal immune system to provide protection to other mucosal sites as well. In this sense, LAB have been used for the development of probiotic foods with the ability to stimulate respiratory immunity, which would increase resistance to infections, even in immunocompromised hosts. On the other hand, the advances in the molecular biology of LAB have enabled the development of recombinant strains expressing antigens from respiratory pathogens that have proved effective to induce protective immunity. In this review we examine the current scientific literature concerning the use of LAB strains to prevent respiratory infections. In particular, we have focused on the works that deal with the capacity of probiotic and recombinant LAB to improve the immune response against Streptococcus pneumoniae. Research from the last decade demonstrates that LAB represent a promising resource for the development of prevention strategies against respiratory infections that could be effective tools for medical application.

Determination of acid alpha-naphthyl acetate esterase enzyme activity in peripheral blood leukocytes of gazelles (Gazella subgutturosa)

We examined gazelle peripheral blood leucocytes using the alpha-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1-2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes.

Differential cytochemical staining characteristics of channel catfish leukocytes identify cell populations in lymphoid organs

This is one of the first characterizations of channel catfish (Ictalurus punctatus) leukocytes by enzyme cytochemistry. Leukocytes demonstrated cytoplasmic staining patterns very similar to mammalian leukocytes when stained with acid phosphatase, alpha-naphthyl butyrate esterase, beta-glucuronidase, alpha-naphthyl acetate esterase, Sudan Black B and anti-immunoglobulin specific immunohistochemistry. Lymphocytes, monocytes, macrophages, neutrophils, and surface immunoglobulin positive (surface Ig+) cells were present in channel catfish renal hematopoietic tissue and spleen and demonstrated distinctive cytoplasmic foci staining patterns, cytoplasmic blushing or cell membrane staining. Monocytes, macrophages, lymphocytes and surface Ig+ cells were present in the thymus. Thymic and splenic cellular organization appeared very similar to these same mammalian tissues. In the thymus, acid phosphatase positive cells were distributed throughout the parenchyma, while alpha-naphthyl butyrate esterase and beta-glucuronidase positive cells were concentrated in the cortex and the medulla, respectively. Surface immunoglobulin positive cells occurred in the cortex. In the spleen, acid phosphatase positive cells were scattered throughout the parenchyma, while alpha-naphthyl butyrate esterase positive cells were scattered throughout the parenchyma and adjacent to splenic arterioles. Beta-glucuronidase and surface immunoglobulin positive cells were restricted to immediately adjacent to splenic arterioles. Sudan Black B positive cells were scattered throughout the parenchyma, while alpha-naphthyl acetate esterase positive cells occurred adjacent to peri-arteriole lymphoid sheaths and appear very similar to mammalian metallophils.

Light and electron microscopic studies on alpha naphthyl acetate esterase activity of the peripheral blood T lymphocytes in van cats

The purpose of this study was to determine the percentage of peripheral blood T lymphocytes and the localization of ANAE enzyme at the electron microscopic level in Van cats by using an alpha-naphtyl acetate esterase procedure. Peripheral blood samples taken from 20 Van cats were used. The percentage of ANAE positive lymphocytes was 83.0%. Neutrophilic granulocytes gave a negative reaction, whereas monocytes, eosinophilic granulocytes showed a diffuse granular positivity. In the electron microscopic examination, ANAE positive reactions were seen in lysosomal granules found in lymphocytes.

Markers of T-cell differentiation and maturation in C57BL/6 and BALB/c mice and in the calf: a comparative study

No significant differences were found between C57BL/6 and BALB/c mice in the levels of Thy 1.2 antigen (a T-cell marker) or the activities of the T-cell maturation-related enzymes adenosine deaminase (ADA, EC 3.5.4.4), serine-esterase (SE, EC 3.4.21), N-acetyl-beta-D-glucosaminidase (NABG, EC 3.2.1.30) and beta-glucuronidase (BG, EC 3.1.1.1), in either unfractionated lymphoid cells or T-lymphocyte-enriched fractions. ADA, SE, NABG and BG activities were much higher (P < 0.01) in the calf than in the corresponding populations in mice. However, the distributions of these activities among thymocyte subpopulations were very similar in mice and the calf. These results provide indirect evidence to suggest that the course of T-cell maturation is similar in mice and the calf.

Possibilities and limitations of cytochemical methods in diagnosis of acute leukemia

Accurate identification and classification of leukemic blast cells is a very important prerequisite of the precise diagnosis of acute leukemia and has a great impact on therapy and prognosis. The purpose of this review is to consider, in the broad sense of the word, the present possibilities and limitations of enzyme cytochemistry and to emphasize how cytochemistry may contribute, on integration with the other methods of study, to the final classification and differential diagnosis of acute leukemia, a highly variable hematological disorder. In this review, the role of conventional enzyme cytochemistry, either dominant or subsidiary, in the discrimination of acute leukemia subtypes is discussed. The survey confirms the absolute necessity of immunologic marker analysis in the accurate diagnosis of acute lymphoblastic leukemia, undifferentiated or minimally differentiated leukemia and mixed-lineage leukemia because in these cases, the cytochemical evaluation provides insufficiently relevant information regarding blast cell origin, specificity of leukemia subtypes and the discrete stages of leukemic cell maturation. On the other hand, cytochemical investigation is appreciated to be dominant over immunophenotyping in characterizing acute myeloid leukemia, because of the lack of specificity of the majority of immunological markers against myeloid antigens and, because of the availability of standardized and sufficiently specific cytochemical reactions. The cytogenetic, molecular biological and electron microscopic studies mentioned in this review supplement the important information for correct differential diagnosis of acute leukemia. The prognostic impact of enzyme cytochemistry in correlation to other methods is evaluated.

Immunosuppression in broilers under experimental aflatoxicosis

The effects of purified aflatoxin B1 on cell mediated immunity in broilers were carried out using 0.3 p.p.m. and 1 p.p.m. dose level. The percentage of acid alpha-naphthyl acetate esterase reacting lymphocytes was significantly (P less than 0.05) decreased in chicks fed 0.3 p.p.m. and 1 p.p.m. level of aflatoxin B1. The albumin and globulin values were also significantly decreased (P less than 0.05) at both dose levels.

Acid hydrolases in B-chronic lymphocytic leukemia (B-CLL): a comparison with normal peripheral B lymphocytes and normal B-cell subset with the phenotype of B-leukaemic cells

The acid phosphatase (AP), beta-glucuronidase (BG), and alpha-naphthyl-acetate esterase (ANAE) distribution and the morphology of stage 0 B-CLL lymphocytes were studied. The results were compared with the same hydrolase equipment and morphology of normal B-cell populations showing the B-CLL-like phenotype, and thus regardable as the possible counterpart of leukaemic cells. The functional and structural characters of the former were strikingly different from those of the latter. In fact the normal B-cell population with B-CLL-like phenotype showed an homogeneous enzyme pattern with predominant ANAE and a strictly lymphocytic cell morphology. In contrast, the leukaemic cells showed various and unrelated morphological and cytochemical features, thus forming apparent subgroups of B-CLL. The development of an irregular "switch on" mechanism in the blocked malignant cell clone, may account for these functional and structural maturation discrepancies. Moreover, the fact that in the leukaemic cells ANAE activity could be demonstrated only after the appearance of the other hydrolases, makes it a marker of functionally differentiated B lymphocytes.

The human T-cell leukemias: clinical, cytomorphologic, immunophenotypic, and genotypic characteristics

The distribution of the conventional lymphoid cell markers on T lymphocytes and the principal panels of monoclonal antibodies used to recognize distinctive T-lymphocyte-associated differentiation antigens are discussed. These reagents have been used to probe the early and late stages of T-cell differentiation, and a hypothetical schema of T-cell differentiation has been constructed. Application of these reagents to the investigation of neoplastic T cells has resulted in the determination of the subset of origin and the stage of differentiation of the neoplastic cells in T-cell-derived lymphoproliferative malignancies. Recent advances in molecular biology have made possible the Southern blot hybridization analysis of DNA extracted from neoplastic T cells for patterns of T-cell-receptor gene rearrangements. Examination of these patterns in benign and malignant T and non-T cell has provided the basis for the use of T-cell-receptor gene rearrangements as specific genetic markers of T-cell lineage, clonality, and differentiation. These and other advances have resulted in the delineation of a new category of T-cell neoplasia, the adult T-cell leukemia/lymphoma syndrome. They have also demonstrated that the majority of clinically indolent neoplasms composed of large granular lymphocytes in so-called T gamma-lymphoproliferative disease are monoclonal proliferations. Further phenotypic, functional, and genotypic analyses of the T-cell malignancies should provide better understanding of T-lymphocyte differentiation and heterogeneity. Such studies should also lead to better clinicopathologic correlations and greater understanding of the basis for the clinical diversity of the T-cell-derived lymphoproliferative malignancies.

The distribution of N-acetyl-beta-glucosaminidase, beta-glucuronidase, acid alpha-naphthyl acetate esterase and alpha-naphthyl acetate esterase in subpopulations of thymocytes, bone marrow cells and other lymphoid organs in mice

Thymocytes, bone marrow lymphocytes, as well as lymphocytes from spleen, lymphoid nodes and peripheral blood were obtained from BALB/c mice. Subpopulations of BALB/c bone marrow T-lymphocyte precursors and immature (small) and mature (large) thymocytes, as established by the percentage of terminal deoxynucleotidyl transferase (TdT) and peanut agglutinin (PNA) positive cells, were obtained by centrifugation on discontinuous density gradients. The activities of N-acetyl-beta-glucosaminidase (NAG), beta-glucuronidase (BG), acid alpha-naphthyl acetate esterase (ANAE) and alpha-naphthyl acetate esterase (NAE) were determined by enzymatic assays of cell extracts of the diverse T-lymphocyte subpopulations, in order to follow their evolution with the maturation of the T-lymphocytes in the thymus. These activities were compared with that determined in lymphocytes from spleen, lymphoid nodes and peripheral blood. The glucidases BG and NAG and the esterases ANAE and NAE present a high decrease in their activities from bone marrow T-lymphocyte progenitors to immature thymocytes. BG, NAG and ANAE activities undergo an about 3-fold increase with the evolution of the thymocytes from small to large cells. Whereas the level of the NAE activity decreases (2-fold) with that evolution of the thymocytes. Lymphocytes from spleen and lymphoid nodes exhibit activities of the glucidases and, specially, the esterases marked by higher than those of thymocyte populations. Peripheral blood lymphocytes also present NAG, ANAE and NAE activities higher than in thymocytes, but their BG activity is lower.

Ultrastructural patterns of the alpha-naphthyl butyrate esterase activity in normal and leukaemic peripheral blood leucocytes

The activity of alpha-naphthyl butyrate esterase was investigated at the ultrastructural level in normal human peripheral blood and in a few cases of hairy cell leukaemia, B-chronic lymphocytic leukaemia and acute monocytic leukaemia. A membrane reactivity was detected in most normal monocytes and lymphocytes. The activity in monocytes was very strong and was inhibited by NaF. It was NaF-resistant and less intense in lymphocytes. The reaction product was localized in the cytoplasm only in a small percentage of lymphocytes. In lymphocytes and monoblasts from pathological samples the pattern of reactivity was similar to that found in their normal counterparts, except for a lower intensity. The hairy cells showed a discrete distribution of the NaF-resistant reaction product on their cell surface. The different patterns of enzyme distribution are discussed critically.

Acid hydrolase activities in B cell chronic lymphocytic leukaemia lymphocytes: correlation of cytochemical reactions with immunological phenotype

The cytochemical reactions of 5 acid hydrolases, alpha-naphthyl acetate esterase (ANAE), acid phosphatase (AP), beta-glucuronidase, beta-glucosaminidase and dipeptidylaminopeptidase IV (DAP IV) were investigated in lymphocytes from 30 patients with B cell chronic lymphocytic leukaemia (B-CLL). Based on ANAE and AP reactivities, 4 cytochemically distinctive subgroups were identified: Group 1: AP and ANAE less than 50% positive lymphocytes (5 cases); Group 2: AP greater than 50%, ANAE less than 50% positive lymphocytes (11 cases); Group 3: AP less than 50%, ANAE greater than 50% positive lymphocytes (7 cases); Group 4: AP and ANAE greater than 50% positive lymphocytes (7 cases). beta-Glucuronidase displayed similar patterns of reactivity to AP. beta-Glucosaminidase activity was observed in the majority of lymphocytes in most patients, whereas DAP IV activity was present in less than 20% of lymphoid cells. The study failed to establish any relationship between cytochemical grouping and patients' clinical status, peripheral lymphocyte counts, E or mouse rosette values, light or heavy chain cellular immunoglobulin (Ig) class. Attempts to correlate acid hydrolase and Ig heavy chain isotype expression, putative markers of B cell maturation, were unsuccessful and indicate that within the narrow spectrum of B cell differentiation seen in B-CLL these characteristics are unrelated.

Characteristic biochemical differences in human T and B lymphocytes separated on nylon wool

T and B lymphocytes from human tonsils were separated on a nylon wool column. T. cells are enriched in the nonadherent, B cells in the adherent fraction. Several enzymes and other markers were tested in separated and non separated lymphocyte populations. Certain enzymes and other properties can be used as T or B lymphocyte markers because of their preferential occurrence and because of the advantages of their estimation (simple, quick methods, objective evaluation). The following characteristics were considered as markers on the basis of our results: (I) acid phosphatase, Na+-K+-activated ATPase, BAEE-peptidase and chromium labeling in T lymphocytes; (II) 5'-nucleotidase, FITC-IgG binding, N-acetyl-D-glucosaminidase, thymidine and valine incorporation in B lymphocytes.

Cytochemical pattern of alpha-mannosidase, alpha-fucosidase and neutral maltase in normal blood cells

The activity of alpha-mannosidase, alpha-fucosidase and neutral maltase was studied by cytochemical techniques in blood cells of 20 controls and of 4 T and B lymphocyte concentrates. All granulocytes, monocytes and platelets showed fine or coarse reaction product deposition, whereas lymphocytes were negative or showed various positivity patterns. A significant difference of the positivity between T and B subpopulations was observed only for the fucosidase reaction. It is possible that the different positivity patterns of the lymphoid cells are related to different functional activities. Further studies will probably confirm the interest of the alpha-fucosidase reaction for the characterization of normal and pathological lymphoid cells.

Non-T, non-B childhood acute lymphoblastic leukemia. Correlation between cytochemical markers and first complete remission

The positivity for four cytochemical reactions, acid phosphatase (AcP), alpha-naphtyl acid acetate esterase (ANAE), beta-glucuronidase (BG), and N-acetyl beta-glucosaminidase (NABG) was correlated to first remission duration in 120 children affected with non-T, non-B acute lymphoblastic leukemia (ALL). The percentages of patients remaining in complete remission at 72 months were always higher for children whose blasts lacked these enzymatic reactions; however, a statistical difference was found only between BG+ and BG- ALL. It also appears that more complete enzymatic patterns of leukemic cells are associated with a poorer prognosis. The percentage of patients still in their first remission was 89% for leukemias with no cytochemical markers, 59% when one reaction was present, but less than 39% when two or more enzymes were detected in the blasts. It is noteworthy that the blasts of patients with more severe prognosis demonstrated a simultaneous positivity for AcP-ANAE or BG-NABG cytochemical reactions. The possible usefulness of these cytochemical markers to detect subsets of patients with different prognostic significance among non-T, non-B ALL is discussed.

Beta-glucuronidase activity in human T and B lymphocytes and the Tmu and T gamma subpopulations

The beta-glucuronidase staining characteristics of isolated T cell populations and the Tmu and T gamma enriched fractions derived of them were studied. T gamma lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The rosette-forming cells in the pellet were referred to as T gamma lymphocytes, whereas the lymphocytes in the interface were referred to as T gamma depleted or Tmu lymphocytes. B cells were studied on rosetted mononuclear cells with either mouse erythrocytes or with Staphylococcus Aureus (Cowan I) bacteria, after a preceeding polyvalent anti-human Ig treatment of the cells. While B cells showed mostly no reactivity, Tmu and T gamma cells were respectively characterised by a "dot-like" and "granular" pattern of reactivity. These findings are in agreement with those observed by others after alpha-naphthyl-acetate esterase or acid phosphatase staining. Within the T lymphocyte fraction, the T non-mu, non-gamma lymphocytes seemed to have a granular pattern of reactivity. The same staining pattern was found in non-B, non-T lymphocytes.

Acid phosphatase and acid esterase activity in neoplastic and non-neoplastic lymphoid cells. A semiquantitative evaluation related to immunological markers in 112 cases

Acid phosphatase (AcP) and acid alpha-naphthylacetate esterase (ANAE) were examined in lymphoid cells from 104 patients suffering from various lymphoproliferative disorders and from 8 healthy controls. Enzyme activities were evaluated by means of a scoring system. Scores of AcP and ANAE were higher in normal T cells than non-T cells. In comparison, the activated T cells in infectious mononucleosis showed increased AcP and decreased ANAE reaction. Malignant T lymphoblasts had a distinct granular AcP positivity in contrast to the faint reactivity observed in cALL blasts, whereas ANAE showed negative or weak reaction in both subsets. High scores and distinct staining patterns for both enzymes were found in T CLL and T prolymphocytic leukaemia, clearly different from the weak activities seen in B CLL, B PLL and some B cell lymphomas. The latter, too, could be distinguished by mutual differences in enzyme reactions. High AcP and ANAE scores were also found in hairy cell leukaemia, and the staining patterns together with the tartrate resistance firmly established the diagnosis. Thus, simultaneous determinations of AcP and ANAE can be of great value in the diagnosis of lymphoid malignancies.

Cytochemistry of human T lymphocyte subpopulations in peripheral blood

With sequential investigation of immunological and cytochemical markers on single cells, T lymphocyte subsets defined by monoclonal antibodies were examined in the peripheral blood of healthy adults. Leu-3a+ T cells (helper/inducer) were 80.0 +/- 6.6% dot positive with unspecific acid alpha-naphthyl acetate esterase (ANAE) and 52.2 +/- 15.8% dot positive with diaminopeptidase IV (DAP IV) staining, as compared to 52.6 +/- 7.6% ANAE and 29.1 +/- 10.9% DAP IV dot positivity in Leu-2a+ T cells (suppressor/cytotoxic). Although these differences were significant (P less than 0.001 and P = 0.002, respectively), the rather high % of dot positivity in Leu-2a+ cells precludes ANAE or DAP IV staining as a simple method for the determination of T lymphocyte subsets. In acid phosphatase staining, no significant difference in focal positivity between Leu3a+ and Leu-2a+ T cell subpopulations was detected (63.3 +/- 10.9% and 52.3 +/- 10.0%, respectively; P greater than 0.1).

Characterization of two patients with lymphomas of large granular lymphocytes

Two patients with non cutaneous well-differentiated lymphocytic lymphoma with leukemic spread are reported. The large majority of their peripheral blood mononuclear cells (PBMC) formed rosettes with sheep erythrocytes, had receptors for the Fc portion of IgG, and an enzymatic profile of relatively mature T-cells. These cells were morphologically characterized as large granular lymphocytes. Studies with monoclonal antibodies in one of the cases showed an OKT3+, OKT10-, OKT4-, OKT8-, HNK-1-, OKM1+ phenotype, whereas PBMC from the other case were OKT3+, OKT10-, OKT4-, OKT8+, HNK-1+, OKM1-. PBMC from the first patient were able to suppress in vitro B-cell differentiation and were capable of a strong antibody dependent cellular cytotoxicity (ADCC) activity. Natural killer (NK) activity was reduced. Cells from the other patient who was hypogammaglobulinemic, exerted suppressor activity in immunoregulatory assays, and showed ADCC and NK activity. These data support the existence of LGL lymphomas consisting of the proliferation of mature appearing cells capable of functional activity.

The distribution of adenosine deaminase, purine nucleotide phosphorylase and 5'-nucleotidase in subpopulations of thymocytes, bone marrow cells and other lymphoid organs in mice

Lymphocyte populations of BALB/c mice were obtained from bone marrow, thymus, spleen, peripheral blood and lymphoid nodes. Subpopulations of thymocytes and bone marrow T-lymphocyte precursors were separated by density gradient centrifugation. The activity of adenosine deaminase (ADA) undergoes a marked increase during the evolution of bone marrow T-cell precursors to immature thymocytes, and a decrease with thymocytes maturation. The peripheral blood lymphocytes (PBL) present the lower activity of the enzyme, and lymphocytes from spleen (SL) and lymphoid nodes (LNL) show activity in the order of that in mature thymocytes. The activity of purine nucleotide phosphorylase (PNP) in the different lymphocytes populations experiments a very little variation with the T-lymphocyte differentiation. With the evolution of T-lymphocyte precursors to immature thymocytes the 5'-nucleotidase (5'-NT) activity experiment a 2-fold decrease. The thymocytes maturation is correlated with an increase in the activity of 5'-NT. The PBL present the maximal activity of the enzyme, whereas in spleen and LNL its levels of activity are in the range of that in mature thymocytes and bone marrow T-cell precursors respectively.

Ultrastructural cytochemistry of chronic T-cell leukaemias. A study with four acid hydrolases

The ultrastructural localization of four acid hydrolases (acid phosphatase, beta-glucuronidase, beta-glucosaminidase and alpha-naphthylacetate esterase) has been studied in lymphocytes from 16 patients with three types of chronic T-cell leukaemia, namely, T-prolymphocytic leukaemia (T-PLL), T-chronic lymphocytic leukaemia (T-CLL) and adult T-cell lymphoma leukaemia (ATLL). Different patterns of enzyme distribution were observed in the leukaemic T-cells from these disorders. In T-PLL, reactivity for the four acid hydrolases was confined to single or a few large granules. Gall bodies were reactive for beta-glucuronidase, b-glucosaminidase and alpha-naphthylacetate esterase but apparently unreactive for acid phosphatase. In T-CLL, scattered small- to medium-size cytoplasmic granules and many parallel tubular arrays were strongly reactive for acid phosphatase, beta-glucuronidase and beta-glucosidase but showed no reactivity for alpha-naphthylacetate esterase. Intermediate features were observed in ATLL. The observed differences in enzyme reactivity reflect a different content of lysosomal granules in the various types of leukaemic T-cells. They also suggest that similar differences may be found in normal T-lymphocyte subsets.

A human thymoma with prothymocyte-like infiltration

We have examined a human thymoma, round-oval epithelial-type cell with moderate lymphocytic infiltration, whose major lymphocytic component (67%), unlike the minor one (33%), did not form rosettes with sheep red blood cells (E rosettes). However, these cells were of T-cell nature as indicated by the positive staining for both acid phosphatase and beta-glucuronidase, two well-accepted cytochemical markers for T cells. The non-E-rosetting lymphocytes expressed T 10, but not T 3 and T 6 antigens. Moreover, they lacked both peanut agglutinin and Fc-IgG receptors. On the contrary, 71 and 19% of the E-rosetting cells were PNA- and Fc-IgM-receptor positive, respectively. Furthermore, the non-E-rosetting cells were phytohemagglutinin unresponsive. The non-E-rosetting lymphocytes were larger (greater than 7 micron) than the E-rosetting cells and showed a different nuclear chromatin pattern. These immunological, cytochemical, and morphological features strikingly resemble those exhibited by cells (prothymocytes) normally found only in fetal thymus. On the basis of these findings we hypothesize the existence in this thymoma of a prothymocyte-like infiltration.

Cytochemistry of normal lymphocyte subsets defined by monoclonal antibodies and immunocolloidal gold

The cytochemical reactivities of 3 acid hydrolases, alpha-naphthyl acetate esterase (ANAE), acid phosphatase and beta-glucuronidase were investigated in normal peripheral blood lymphocyte subsets defined by monoclonal antibodies OKT3, 4, 8 and FMC4 (anti-Ia). A combined monoclonal antibody-immunocolloidal gold/cytochemical staining procedure was used to determine enzyme activities and distributions of reaction product in each subset. Cytochemical profiles for each lymphocyte subset were defined. The majority (greater than 85%) of T cells (OKT3+) were positive for all 3 enzymes whereas a minority (less than 40%) of B cells (FMC4+) displayed reactivity. The cytochemical profiles of T helper/inducer (OKT4+) and T suppressor/cytotoxic (OKT8+) cells were not significantly different and corresponded to that observed for OKT3+ cells; thus none of these enzymes can be used to distinguish normal lymphocyte subsets cytochemically. ANAE reactions were further analysed, in the respective subsets, on the basis of dot-like or scattered/diffuse reactivity. The ratios of cells displaying dot-like: scattered/diffuse reactivity, in the respective subsets, were OKT3+, 5.4:1; OKT4+, 8.1:1; OKT8+, 2.4:1; FMC4+, 0.4:1. The cytochemical profiles and ANAE reactivities of T cell subsets identified by monoclonal antibodies differ from those displayed by T cell subsets defined by Fc receptors and confirms that there is little correlation between subsets defined by these two methods.

T-lymphocyte and B-lymphocyte dichotomy in anuran amphibians: I. T-lymphocyte proportions, distribution and ontogeny, as measured by E-rosetting, nylon wool adherence, postmetamorphic thymectomy, and non-specific esterase staining

We used sheep erythrocyte (SRBC) E-rosetting, nylon wool fractionation thymectomy and nonspecific esterase staining to assess T-lymphocyte characteristics in Rana pipiens during various developmental stages. T-lymphocytes appear in the spleens of premetamorphic tadpoles. We found significant levels of lymphocytes classifiable as T-cells in the peripheral blood of adults, but fewer numbers of T-cells in the thymus, jugular bodies, spleen, pronephros, mesonephros, liver and bone marrow. In addition, thymectomized Xenopus laevis showed a sharp decrease in T-cells as evidenced by E-rosetting, ANAE stain and nylon wool fractionation. The presence of T-lymphocytes in anuran amphibians and the existence of a receptor for SRBC on a population of these cells, suggest conservation of T-cells during evolution.

Cytochemical analysis of human peripheral blood lymphocyte subsets defined by monoclonal antibodies

Human blood lymphocyte subpopulations, revealed by a panel of commercially available monoclonal antibodies by means of a rosetting technique, were submitted to direct cytochemical analysis and were shown to have distinguishing characteristics. T cells reactive with OKT3 antibody (T3+) displayed higher beta-glucuronidase and dot-like alpha-naphthyl acetate acid esterase (ANAE) activity than T3- cells. Helper/inducer cells (T4+) were characterized by a high level of dot-like ANAE activity, whereas cytotoxic/suppressor cells (T8+) displayed selective naphthol-ASD-chloroacetate esterase activity. These results provide evidence for association of some cytoplasmic enzyme activities with the expression of membrane differentiation markers defined by monoclonal antibodies.

Enzyme alterations in leukemic cells

Recently, much attention has been focused on various enzyme alterations found in leukemic cells. Most of the data generated thus far has involved the study of terminal deoxynucleotidyl transferase, the purine pathway enzymes, and hexosaminidase and other lysosomal enzymes. Differences in both total enzyme activities and isoenzyme patterns have been found to occur among the various leukemia types and subtypes. These changes may prove to be useful aids in diagnosing, classifying, detecting subclinical recurrent or residual disease, and as therapeutic determinants in hematopoietic neoplasia, especially in the lymphoid malignancies.

The morphology and cytochemistry of human T-cell subpopulations defined by monoclonal antibodies and Fc receptors

Leu 2a+ (suppressor/cytotoxic) and Leu 3a+ (helper/inducer) T-cell subsets of normal peripheral blood lymphocytes, purified by fluorescence-activated cell sorting, respectively showed 50 +/- 22% (range 31-92%) and 82 +/- 9% (range 69-93%) dot non-specific esterase (NSE) and 48 +/- 20% (range 31-91%) and 79 +/- 10% (range 64-92%) dot acid-phosphatase (APase) staining. Mature T cells defined by monoclonal antibody (UCHT1) displayed 81% and 79% dot NSE and APase positivity, while E-rosetting cells not staining with UCHT1 showed only 15% and 10% dot-positivity and were generally larger cells with more abundant cytoplasm. Examination of Fc-rosetting cells within the different T-cell subsets showed that dot positivity was not directly related to microFc receptor (microFcR) expression; particularly among Leu 2a+ lymphocytes, many microFcR+ cells lacked dot staining. It is concluded that dot staining for hydrolytic enzymes is a marker of true T-cells (as defined by monoclonal antibodies), although a minority of such cells (approximately 20%) lack this staining pattern. Although Leu 3a+ cells display a higher percentage of dot positivity than do Leu 2a+ cells, the difference is not clinically useful, and the two cell populations are not readily distinguishable on morphological grounds. The previously reported association between dot staining and microFc receptor expression is shown to be an indirect one, attributable to the fact that most T-cells, defined by monoclonal antisera, possess microFcR whereas most E+ UCHT1- cells lack microFcR.

Alpha-naphthyl acetate esterase activity in human foetal lymphocytes

Human foetal mononuclear cells from thymus, spleen, liver, bone marrow and peripheral blood at 8-24 weeks of gestation were examined for cytochemical evidence of acid alpha-naphthyl acetate esterase (ANAE) activity. The focal brownish-red ANAE reaction product (T cell staining pattern) was observed in counterstained cytocentrifuged cell smears in the cytoplasm. ANAE-positive lymphoid cells were first observed in the thymus at 9 weeks of gestation. A gradual increase in frequency of ANAE-positive cells in foetal thymus was observed, from about 10% at 14-15 weeks to about 20% at 22-24 weeks of gestation. By 14 weeks of foetal age, spleen and liver contained a few ANAE-positive cells and after 15 weeks of gestation consistent occurrence of ANAE-positive cells was observed in foetal bone marrow and peripheral blood. These results demonstrate that ANAE-positive lymphocytes first appear in the foetal thymus and are subsequently found in the foetal liver, spleen, bone marrow and peripheral blood.

Phenotypic heterogeneity of human T-cell malignancies: demonstration by monoclonal antibodies and cytochemical markers

The present study sought to delineate the phenotypic heterogeneity of the human T-cell malignancies. Twenty T-cell neoplasms were investigated for reactivity with the OKT hybridoma monoclonal antibodies and expression of acid alpha-naphthyl acetate esterase (ANAE), beta-glucuronidase (BG), and acid phosphatase (AP) activity. Twelve cases (Mycosis fungoides, Sezary syndrome, cutaneous T-cell lymphoma, chronic lymphocytic leukemia) were OKT3'T4', ie, expressed the phenotype commonly associated with mature T-helper cells. These cases were further divisible into ANAE+BG+ (6 cases), ANAE-BG+ (5 cases), and ANAE-BG- (1 case) phenotypes. In contrast to the 12 OKT3+T4+ cases, the remaining 8 cases showed considerable inter- and intratumor heterogeneity with respect to reactivity with the OKT antibodies. Six of these cases (acute lymphoblastic leukemia, lymphoblastic lymphoma) expressed phenotypes consistent with various intrathymic stages of T-cell differentiation. Five of the latter 6 cases were AP+BG+ANAE-, analogous to the majority of normal cortical thymocytes; an OKT3+T4-T8+T10+ neoplasm was ANAE+, analogous to normal medullary thymocytes. Two cases expressed the previously undescribed OKT3+T4-T8-T10+ phenotype. These studies demonstrate that the T-cell malignancies are divisible into phenotypes which correspond to normal maturational stages of T-cell differentiation and functionally distinct T-cell subsets. Phenotypic analysis of the human T-cell malignancies may provide a basis for understanding their biological heterogeneity and may aid in the identification of transitional stages of T-cell differentiation and minor T-cell subsets.

T cell leukemia presenting as chronic polyarthritis

T cell leukemia was detected in a woman who suffered from chronic polyarthritis. The peripheral blood leukocytes were increased in number and consisted of lymphocytes, 95% of which could be identified as T lymphocytes. T cell infiltration was found in the bone marrow, the synovial fluid, and tissue, and in nodules macroscopically resembling rheumatoid skin lesions. Further investigation of these cells by enzyme chemistry, immunohistochemistry, electron microscopy, and cytochemistry revealed that they had irregularly indented nuclei, no alpha-naphthyl acetate esterase activity, and only faint granular acid-phosphatase activity. The cells were negative for Ia-like antigen and surface immunoglobulin. Analysis of the cell surface glycopeptides showed the presence of abnormally enlarged carbohydrate structures. These data suggest that these leukemic T cells are a malignant equivalent of immature T cells.

Acid alpha-naphthyl acetate esterase activity in nucleated red cells of human fetal liver

Acid alpha-naphthyl acetate esterase (ANAE) activity was investigated in nucleated red cells obtained from nine human fetal livers at 9-24 weeks of gestation. A strong ANAE activity was demonstrated in fetal liver erythroblasts with a staining pattern of a perinuclear ring. Occasionally some polychromatophilic normoblasts expressed a focal ANAE activity usually observed in human T-lymphocytes. Some 50-70% of erythroblasts in human fetal livers showed a ring-like staining pattern. A slight decrease of ANAE positivity was observed in cells of fetal livers after 17 weeks of gestation.