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Results for “Immunophenotyping”

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PubMed1997

The immunophenotypic characterization of bovine lymphomas.

A prospective analysis of 38 cases of bovine lymphoma was performed. Thirty-five of the lymphomas were considered enzootic because of serologic or molecular biologic association with the bovine leukemia virus (BLV). The three remaining cases were in cattle < 1 year of age and were not associated with BLV and hence were considered sporadic lymphomas. Utilizing the national cancer Institute Working Formulation for the morphologic classification of human non-Hodgkin's lymphoma, 54.3% (19/35) of the enzootic lymphomas were classified as the diffuse large cleaved cell type. The cells of the 35 enzootic lymphomas expressed a consistent immunophenotype represented by MHCII+, gamma-heavy chain+, and lambda-light chain+; this constellation of markers indicated a mature B-cell phenotype. The three sporadic lymphomas failed to express MHCII antigen despite the presence of other B-cell antigens. There was no correlation between morphologic cell type and immunophenotype in these bovine lymphomas.

Animals↗

PubMed2002

Clinical impact of the differentiation profile assessed by immunophenotyping in patients with diffuse large B-cell lymphoma.

To analyze the relationship between immunophenotyping profile and main clinicopathological features and outcome in diffuse large B-cell lymphoma (DLBCL), we studied 128 patients (59 men, 69 women; median age 65 years) consecutively diagnosed with de novo DLBCL in a single institution. Cells from each patient were immunostained with CD20, CD79a, CD5, CD10, bcl-6, MUM1, CD138, bcl-2, p53, p27, and Ki-67 antibodies. Four immunophenotyping profiles were distinguished according to the pattern of differentiation: germinal center-CD10(+) (GC-CD10(+); CD10(+)/Bcl-6(+)/MUM1(-)/CD138(-)), germinal center-CD10(-) (GC-CD10(-); CD10(-)/Bcl-6(+)/ MUM1(-)/CD138(-)), post-germinal center (pGC; CD10(-)/bcl-6(+/-)/ MUM1(+)/CD138(-)), and plasmablastic (CD10(-)/bcl-6(-)/MUM1(+)/CD138(+)). Rearrangement of bcl-2 was studied by polymerase chain reaction (PCR) in 57 patients. Single-antigen expression was as follows: CD5, 2%; CD10, 21%; bcl-6, 72%; MUM1, 54%; CD138, 2%; bcl-2, 59%; p53, 28%; p27, 40%. Distribution according to differentiation profiles was as follows: GC-CD10(+), 24 patients, GC-CD10-, 30 patients; pGC, 60 patients; plasmablastic, 2 patients; other patterns, 12 patients. The pGC profile was associated with primary nodal presentation and immunoblastic morphology, whereas GC-CD10(+) tumors showed disseminated disease, centroblastic morphology, bcl-2 rearrangement, and lower Ki-67 proliferative index. GC-CD10(-) patients more often presented with primary extranodal origin, early stage, normal lactic acid dehydrogenase (LDH) levels, and low or low/intermediate International Prognostic Index (IPI) scores than the others. However, no significant difference was found in terms of response or overall survival (OS) according to these profiles. Expression of bcl-2 was associated with advanced stage, high or high-intermediate IPI, and poor OS. Expression of bcl-2 maintained predictive value in multivariate analysis, with stage and LDH. In conclusion, differentiation profile was associated with particular clinicopathological features but was not essential to predicting outcome in DLBCL patients.

Adult↗

PubMed2004

Unusual immunophenotype of CD8+ T cells in familial hemophagocytic lymphohistiocytosis.

Familial hemophagocytic lymphohistiocytosis (FHL) is an inherited, fatal disorder of infancy. We report here a 17-day-old female infant who presented with high fever, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, thrombocytopenia, and liver failure. Leukocytosis was detected with circulating "atypical" lymphoid cells. Flow cytometric studies revealed expanded subpopulations of CD8+ T cells with unusual immunophenotypic features, including a subset that lacked CD5 expression. A liver biopsy showed hemophagocytic lymphohistiocytosis with exuberant infiltrates of CD8+ T cells that lacked perforin. Mutational studies revealed a 666C-->A (H222Q) missense mutation in the perforin gene. T-cell receptor studies on flow-sorted T-cell subpopulations revealed no evidence of monoclonality. Analysis of T-cell receptor excision circle levels indicated long proliferative history in the aberrant CD8+ T-cell subsets. This case provides an instructive example of uncontrolled reactive proliferation of CD8+ T cells in FHL, resulting in atypical morphology and unusual immunophenotypic features that might suggest malignancy in other clinical settings.

Biopsy↗

PubMed2005

AIDS-related B-cell lymphoma (ARL): correlation of prognosis with differentiation profiles assessed by immunophenotyping.

This study was undertaken to analyze the differentiation profiles assessed by immunophenotyping in AIDS-related B-cell lymphoma (ARL) and their relation to the clinical course. Paraffin-embedded sections of 89 ARL cases during 1989 to 2004 were stained immunohistochemically with antibodies to CD3, CD10, CD20, CD38, CD138/Syndecan-1 (Syn-1), multiple myeloma-1/interferon regulatory factor-4 (MUM1/IRF4), B-cell lymphoma protein-2 (BCL-2), BCL-6, latent membrane protein-1 (LMP-1), and Ki-67. Expression of CD10 and CD20 were associated with better overall survival (OS; P = .009 and P = .04, respectively). Expression of CD20 was associated with longer disease-free survival (DFS; P = .03), whereas expression of CD138/Syn-1 was associated with shorter DFS (P = .03). OS and DFS were worse in patients with immunophenotypic profiles related to post-germinal center (GC) differentiation (BCL-6 and CD10 negative, MUM1/IRF4 and/or CD138/Syn-1 positive) when compared with GC differentiation (P = .01). When controlled for age-adjusted International Prognostic Index (IPI), prior AIDS-defining illness (ADI), and year of ARL diagnosis, a post-GC differentiation remained significantly associated with poor OS and DFS. Expression of CD10 was associated with a preserved immunocompetence, whereas CD20 was less frequent in patients developing ARL while on highly active antiretroviral therapy (P = .04). In summary, lack of CD20 or CD10 expression and a post-germinal center signature are associated with a worse prognosis in ARL.

Adult↗

PubMed2001

Early immunophenotypical evaluation of minimal residual disease in acute myeloid leukemia identifies different patient risk groups and may contribute to postinduction treatment stratification.

Early response to therapy is one of the most important prognostic factors in acute leukemia. It is hypothesized that early immunophenotypical evaluation may help identify patients at high risk for relapse from those who may remain in complete remission (CR). Using multiparametric flow cytometry, the level of minimal residual disease (MRD) was evaluated in the first bone marrow (BM) in morphologic CR obtained after induction treatment from 126 patients with acute myeloid leukemia (AML) who displayed aberrant phenotypes at diagnosis. Based on MRD level, 4 different risk categories were identified: 8 patients were at very low risk (fewer than 10(-4) cells), and none have relapsed thus far; 37 were at low risk (10(-4) to 10(-3) cells); and 64 were at intermediate risk (fewer than 10(-3) to 10(-2) cells), with 3-year cumulative relapse rates of 14% and 50%, respectively. The remaining 17 patients were in the high-risk group (more than 10(-2) residual aberrant cells) and had a 3-year relapse rate of 84% (P =.0001). MRD level not only influences relapse-free survival but also overall survival (P =.003). The adverse prognostic impact was also observed when M3 and non-M3 patients with AML were separately analyzed, and was associated with adverse cytogenetic subtypes, 2 or more cycles to achieve CR, and high white blood cell counts. Multivariate analysis showed that MRD level was the most powerful independent prognostic factor, followed by cytogenetics and number of cycles to achieve CR. In conclusion, immunophenotypical investigation of MRD in the first BM in mCR obtained after AML induction therapy provides important information for risk assessment in patients with AML.

Acute Disease↗

PubMed2001

Immunophenotypic profiles in families with autoimmune lymphoproliferative syndrome.

Autoimmune lymphoproliferative syndrome (ALPS) type Ia is caused by inherited defects in apoptosis and is characterized by nonmalignant lymphoaccumulation, autoimmunity, and increased alpha/beta(+) double-negative T cells (alpha/beta(+)-DNT cells). This study reports immunophenotypic findings in 166 members of 31 families with ALPS type Ia, associated with genetic mutations in the TNFRSF6 gene encoding Fas. The ALPS type Ia probands (n = 31) and relatives having both a Fas mutation and clinically proven ALPS (n = 28) showed significant expansion of CD8(+) T cells, alpha/beta(+)-DNT cells, gamma/delta(+)-DNT cells, CD3(+)/ HLA-DR(+) T cells, CD8(+)/CD57(+) T cells, and CD5(+) B cells. Relatives with Fas mutations, but without all the required criteria for ALPS (n = 42), had expansions of CD8(+) T cells, alpha/beta(+)-DNT cells, and gamma/delta(+)-DNT cells. Interestingly, relatives without a Fas mutation and with no features of ALPS (n = 65) demonstrated a small but significant expansion of CD8(+) T cells, both DNT cell subsets, and CD5(+) B cells. As compared to unrelated healthy controls, lymphocyte subset alterations were greatest in the probands, followed by the relatives with mutations and ALPS. Probands and relatives with mutations and ALPS also showed a lower number of CD4(+)/CD25(+) T cells that, in combination with an independent increase in HLA-DR(+) T cells, provided a profile predictive of the presence of clinical ALPS. Because quantitative defects in apoptosis were similar in mutation-positive relatives regardless of the presence of clinical ALPS, factors, other than modifiers of the Fas apoptosis pathway, leading to these distinctive immunophenotypic profiles most likely contribute to disease penetrance in ALPS.

Adult↗

PubMed2004

Flow cytometric immunophenotyping analysis of patterns of antigen expression in non-Hodgkin's B cell lymphoma in samples obtained from different anatomic sites.

Multiparametric clinical flow cytometry has evolved from two-parameter quantitative assessment of lymphocytes to assessment of many qualitative parameters of suspensions obtained from bone marrow, peripheral blood, and lymph nodes for hematopathology. Nowadays, lymphoma immunophenotyping is a necessary complement to morphology and molecular parameters in the diagnosis and monitoring of human hematopoietic malignancies. The aim of the present study was to determine whether immunophenotypic differences could be used to distinguish between non-Hodgkin's B cell lymphoma (NHL-B) and the normal B cell subpopulation by assessing the variability in the patterns of expression of some lymphoid antigens (CD5, CD19, FMC7, CD23, CD20, CD79b, CD38, CD22, CD10, sIgkappa, sIglambda, mIgA, mIgG, mIgM, and mIgD) in specimens obtained from patients with NHL-B. We have studied peripheral blood samples, lymph node suspensions, and bone marrow specimens from 20 patients with malignant lymphoma and from controls without oncohematologic disease. Some patients showed stable patterns of antigen expression that remained unchanged over time and were consistent from one specimen to another. Other patients showed more variability in the pattern of antigen expression from different specimens. The two-way cluster analysis of antigens revealed three patterns of expression: (1) most cells in most cases positive (CD5, CD19, CD20, CD23, CD45); (2) most cells in most cases negative (CD10, mIgG, CD22, CD23,CD38); and (3) a mixed pattern with a variable number of positive cases and a variable percentage of positive cells in individual cases (CD22, CD38, CD79b, FMC7, mIgD, mIgM, mIgA, mIgG, sIgkappa, sIglambda). The expression of several antigens was strongly interdependent, even when antigens belonged to entirely different gene families. Such antigen pairs were CD19/CD45; CD19/CD79b; CD23/Igkappa; and CD45/CD79b. Our results suggest that different factors may determine the stability or the variability of such multiantigen expression, particularly the biology and function of the different antigens and the mechanisms of disease dissemination and progression.

Aged↗

PubMed1993

Expression of P-glycoprotein and glutathione-S-transferase in recurrent lymphomas: the possible role of Epstein-Barr virus, immunophenotypes, and other predisposing factors.

PURPOSE: We previously have reported the poor prognoses of recurrent peripheral T-cell lymphoma (PTCL) and Epstein-Barr virus (EBV)-associated PTCL (J Clin Oncol 7:725-731, 1989; Blood 77:799-808, 1991). To study the role that drug resistance plays in this scenario, we conducted a retrospective study of 23 adult patients. PATIENTS AND METHODS: All patients had recurrent lymphoma tissue available for immunophenotyping and screening for the existence of EBV DNA in tumor cells by Southern blot analysis and in situ hybridization. Expression of a multidrug resistance P-glycoprotein ([P-gp]mdr-1) and a glutathione redox cycle-related glutathione-S-transferase pi (GST-pi) was determined by an immunohistochemistry method. RESULTS: Expression of mdr-1 or GST-pi was found in 11 (48%) and 12 (52%) cases, respectively. Most (11 of 12) of the GST-pi expression occurred simultaneously with mdr-1. Prechemotherapy tumor tissues were available in 11 cases; only two (18.2%) of these cases expressed mdr-1. Four (36%) of 11 cases that expressed mdr-1 (mdr-1(+)) and nine (90%) of 10 cases that did not express mdr-1 (mdr-1(-)) responded to second-line chemotherapy (P < .05). The survival-after-recurrence (SAR) curves significantly favored mdr-1(-) recurrent lymphoma (P < .05). The mdr-1 expression was further correlated with the immunophenotype and EBV association. All six cases of EBV-associated lymphoma (PTCL, five cases; Hodgkin's disease, one case) had significant simultaneous expression of mdr-1 and GST-pi in their recurrent tumor tissues. CONCLUSION: (1) mdr-1 expression is a significant prognostic factor in recurrent lymphomas; (2) high expression of mdr-1 is observed in recurrent EBV-associated PTCL; and (3) GST-pi usually expresses simultaneously with mdr-1 in recurrent lymphomas. The role of EBV in the development of mdr-1 and the biologic significance of the simultaneous expression of mdr-1 and GST-pi in recurrent lymphomas are well worth further exploration.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1993

Immunophenotypes and karyotypes of leukemic cells in children with Down syndrome and acute lymphoblastic leukemia.

PURPOSE: Immunophenotypes and karyotypes of leukemic cells were analyzed in a large series of Down syndrome patients with acute lymphoblastic leukemia (ALL) to examine the frequency of adverse prognostic features in comparison with other patients with ALL. PATIENTS AND METHODS: Presenting features and leukemic cell characteristics were compared for 76 patients with Down syndrome and 4,733 other patients with newly diagnosed ALL treated on protocols of the Pediatric Oncology Group (POG) and St Jude Children's Research Hospital (SJCRH). Treatment outcome was analyzed for the patients with non-T-cell disease enrolled on a single trial, for whom adequate follow-up data were available. RESULTS: Down syndrome patients had lower platelet counts (P < .01) and were less likely to have an anterior mediastinal mass (P < .01) or CNS leukemia (P = .01). They were significantly more likely to have the pre-B immunophenotype (49% v 25.5%, P < .01) and less likely to have T-cell ALL (5.5% v 16%, P = .01). There was a notable absence among patients with Down syndrome of the t(4;11), t(1;19), and t(9;22), which are chromosomal translocations associated with an adverse prognosis in ALL. Treatment outcome did not differ significantly between patients with Down syndrome and the other children with non-T-cell ALL (P = .21); a third of the treatment failures in the former group resulted from treatment-related toxicities. CONCLUSION: Children with Down syndrome and ALL had a low frequency of adverse clinicobiologic features at diagnosis. However, these findings did not translate into a superior outcome, apparently because of treatment-related toxicity in this group. Future trials should focus on pharmacokinetics and other strategies to reduce toxicity in these compromised patients.

Adolescent↗

PubMed1996

Heterogeneity in the origin and immunophenotypes of "histiocytic" cells in transplantable rat malignant fibrous histiocytoma.

To clarify the origin and nature of "histiocytic" cells in malignant fibrous histiocytoma (MFH), immunoreactivities to rat macrophage/histiocyte-specific monoclonal antibodies (ED1 and ED2) and monocyte chemoattractant protein-1 (MCP-1) production were investigated using rat transplantable MFH-derived cloned cells (undifferentiated MT-8 and fibrohistiocytic MT-9). In different cultures, the positive rates for ED1 and ED2 ranged from 2.5% to 26.0% in MT-8, and from 6.0% to 40.0% in MT-9. In homotransplants, ED1-positive cells were frequently observed in MT-9 tumors, but barely seen in MT-8 tumors. In both MT-8 and MT-9 tumors, ED2-positive cells were not detected within tumors. Immunophenotypic characteristics of MT-8 and MT-9 to these antibodies seemed to be easily altered depending on in vitro and in vivo conditions. By ELISA, MCP-1 was hardly detected in culture supernatants of MT-8 and MT-9, but its level was very high in sera of MT-8- and MT-9-tumor-bearing rats. In rats with these tumors, the number of circulating monocytes was significantly increased and the presence of factors stimulating macrophage proliferation was demonstrated by the colony formation assay using rat bone marrow cells. Histiocytic cells in MT-8 and MT-9 tumors that were produced in nude mice reacted only with antibody to mouse macrophage-associated antigen. This suggests the existence of non-neoplastic, infiltrated macrophages of host origin that were induced probably by MCP-1 and factors stimulating macrophage proliferation. The present studies indicate the presence of heterogeneities in the origin and immunophenotypes of "histiocytic" cells in rat MFH.

Animals↗

PubMed2006

Morphologic and immunophenotypic analysis of angioimmunoblastic T-cell lymphoma: Emphasis on phenotypic aberrancies for early diagnosis.

The morphologic features and immunophenotype of diagnostic nodal and bone marrow biopsy specimens were reviewed in 29 well-established cases of angioimmunoblastic T-cell lymphoma (AILT). All cases showed a characteristic polymorphous lymphoid and inflammatory cell infiltrate along with stromal-vascular changes. Perivascular aggregation or clustering of neoplastic clear cells was seen in only 41% of cases. Unique architectural changes, including extranodal extension (83%), follicular dendritic cell proliferation (93%), and a distinctly marginalized distribution of residual B cells (67%) were observed. Subsets of T cells with immunophenotypic abnormalities (CD10 coexpression or loss of pan-T-cell antigens CD3 and CD7) were identified in a majority of cases (96%). Significantly, these morphologic and phenotypic features were seen irrespective of the presence of an overt lymphomatous pattern. Bone marrow involvement was present in 90% of patients with available biopsy specimens. Our results indicate that unique morphologic alterations and subsets of phenotypically aberrant T cells are present consistently in nearly all cases of AILT, including morphologically less definitive biopsy specimens.

Adult↗

PubMed2005

Immunophenotypic profile of lymphoplasmacytic lymphoma/Waldenström macroglobulinemia.

We retrospectively reviewed the immunophenotypic profile of 75 cases of lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) analyzed by flow cytometry. All patients had monoclonal IgM (median, 2,100 mg/dL [21 g/L]) in serum and were considered clinically to have WM. The neoplastic cells, in all cases, expressed monoclonal immunoglobulin light chain (k, 55; l, 20) and CD19, and every case assessed was positive for CD20 (n=68) and CD52 (n=60). The results for other antigens assessed in decreasing frequency of positivity were as follows: surface IgM (26/28 [93%]), CD79b (11/13 [85%]), CD11c (13/16 [81%]), CD25 (5/7 [71%]), CD23 (17/28 [61%]), CD38 (24/50 [48%]), FMC7 (11/29 [38%]), CD22 (4/12 [33%]), CD5 (3/65 [5%]), and CD10 (1/38 [3%]). These results show that the immunophenotype of LPL/WM is variable and overlaps with other B-cell lymphoproliferative disorders. CD23, usually of dim intensity, and CD11c are expressed commonly in LPL/WM. Rare CD5+ and CD10+ cases of LPL/WM also exist.

Adult↗

PubMed2007

Stability of leukemia-associated immunophenotypes in precursor B-lymphoblastic leukemia/lymphoma: a single institution experience.

Essentially all cases of precursor B-lymphoblastic leukemia/lymphoma (B-ALL) demonstrate multiple immunophenotypic aberrancies relative to normal maturing B-cell precursors (hematogones). The stability of these aberrancies has relevance to follow-up minimal residual disease analysis. We compared the immunophenotypes at diagnosis and relapse in 51 childhood and adult B-ALLs with flow cytometry (FC) using broad antibody panels. A total of 446 aberrancies were present at diagnosis (median, 9 per case; range, 2-14). All cases retained multiple aberrancies at relapse (median, 8 per case; range, 2-14). Antibody panels at relapse allowed assessment of 383 (85.9%) of the initial 446 aberrancies. Of these, 299 (78.1%) were persistent and 84 (21.9%) were lost at relapse. Overall, 73% of cases showed a loss of at least 1 aberrancy at relapse. However, new aberrancies were detected in 60% of cases. These findings suggest that FC is suitable for the detection of residual B-ALL, provided that follow-up studies are not too narrowly targeted.

Adolescent↗

PubMed2000

A relational database for diagnosis of hematopoietic neoplasms using immunophenotyping by flow cytometry.

A relational database was developed to facilitate the diagnosis of hematopoietic neoplasms using results of immunophenotyping by flow cytometry. This database runs on personal computers and uses backward-chaining search to arrive at conclusions. Results of immunologic marker studies are processed by the database to obtain a set of differential diagnoses. The current version of this database includes diagnostic immunophenotyping pattern for 33 hematopoietic neoplasms. We tested this database using 92 clinical cases from 2 tertiary care medical centers. The database ranked the actual diagnosis as 1 of the top 5 differential diagnoses in 93% of the cases tested. The user can modify the database contents to suit individual needs. This database has been posted on the World Wide Web for direct access. We propose that this user-friendly database is a potential tool for computer-assisted diagnosis of hematopoietic neoplasms.

Antigens, CD↗

PubMed2002

Transient stress lymphocytosis: an immunophenotypic characterization of the most common cause of newly identified adult lymphocytosis in a tertiary hospital.

We prospectively evaluated 52 consecutive cases of newly identified absolute lymphocytosis to determine the hematologic and immunophenotypic features of transient stress lymphocytosis (TSL). The lymphocytosis in all cases was associated with an acute stressful event and ranged from 4,000 to 10,400/microL (4.0-10.4 x 10(9)/L). Compared with healthy individuals, patients with TSL showed an increase in the total WBC, absolute lymphocyte (ALC), absolute neutrophil (ANC), and platelet counts with no difference in hemoglobin levels. Immunophenotypic analyses of 38 cases revealed increases in absolute numbers of T B, and natural killer cells. Both CD4+ and CD8+ T cells were increased, predominantly accountedfor by an increase in memory cell subsets, with no change in gamma/delta T cells. Follow-up studies showed a significant reduction in the ALC with a concurrent increase in the ANC and reduction in hemoglobin values. The reduction in lymphocytes at resolution was accompanied by reduction in all broad Iymphocyte subsets. However, naive and memory subsets showed different patterns of alteration within the CD4+ and CD8+ populations, suggesting that acute stress differentially affects the in vivo distribution of these subsets.

Adolescent↗

PubMed2005

Flow cytometric immunophenotyping of adult T-cell leukemia/lymphoma using CD3 gating.

Adult T-cell leukemia/lymphoma (ATLL) is a lymphoproliferative neoplasm of helper T lymphocytes caused by human T-cell leukemia virus type-1 (HTLV-1). The disease was first described in Kyushu, in southwestern Japan, and most frequently occurs in endemic areas, such as Japan, the Caribbean basin, West Africa, Brazil, and northern Iran. ATLL is essentially a disease of adults, characterized clinically by generalized lymphadenopathy, hepatosplenomegaly, skin lesions, and hypercalcemia. The prognosis of most patients is quite poor, with a median survival time of only 13 months, even if multiagent combination chemotherapy is given. In the present study, flow cytometric immunophenotyping with CD3 gating was performed on 30 samples from 26 patients who had been given a diagnosis of ATLL. The records of these patients also were reviewed retrospectively. In 14 of the 30 samples, an abnormal CD3(low) T-cell population was distinguishable from the normal T-cell populations by flow cytometric analysis. Herein we report a novel strategy for flow cytometric immunophenotyping of ATLL facilitated by CD3(low) gating.

Adult↗

PubMed2001

High resolution immunophenotypic analysis of chronic lymphocytic leukemic cells by enzymatic amplification staining.

Immunophenotypic analysis of chronic lymphocytic leukemia (CLL) cells is essential for the diagnosis of this disorder. Unfortunately, surface immunoglobulin light chains and CD79b are expressed faintly or not at all by CLL cells from many patients. We developed an enzymatic amplification staining procedure that amplifies the fluorescent signal by 10- to 100-fold. By using this technology, we have been able to resolve immunoglobulin light chain exclusion and CD79b expression on the cells from most cases. This new capability can be used for high-resolution immunophenotypic analysis of leukemias and lymphomas.

Antigens, CD↗

PubMed2002

Terminal deoxynucleotidyl transferase-positive lymphoid cells in reactive lymph nodes from children with malignant tumors: incidence, distribution pattern, and immunophenotype in 26 patients.

The presence of terminal deoxynucleotidyl transferase (TdT)-positive lymphoid precursors in benign lymph nodes from children has been characterized insufficiently. By using single- and double-labeling immunohistochemical analysis, we examined the frequency, distribution, morphologic features, and immunophenotype of TdT-positive cells in benign lymph nodes from 26 consecutive pediatric patients (4 boys, 22 girls; age, 10 weeks-17 years; median, 4.5 years), 23 of whom had a history of malignant neoplasm. We identified TdT-positive lymphoid cells in all 26 cases. These cells were found adjacent to medullary and cortical sinuses, with a frequency of 1 to 180 cells per high-powerfield (median, 20 cells), and were present singly and in small clusters. They were morphologically heterogeneous and showed a precursor B-cell immunophenotype including colocalization with CD34 by single-antibody immunohistochemical analysis and coexpression of variable levels of CD79a and CD10 and lack of CD3 expression by double immunostaining. These features should aid in the evaluation of pediatric lymph nodes for partial involvement by lymphoblastic lymphoma/leukemia.

Adolescent↗