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Epithelial membrane antigen (EMA) or MUC1 expression in monocytes and monoblasts

Leong CF, Raudhawati O, Cheong SK, Sivagengei K, Noor Hamidah H

Pathology, 2003 Oct;35(5):422-7.
PMID: 14555387

AIMS: Epithelial membrane antigen (EMA) or MUC1 belongs to a heterogeneous group of heavily glycosylated proteins and is expressed in most normal and epithelial neoplastic cells. EMA is also expressed in plasma cells, anaplastic large cell lymphoma (Ki-1 antigen), malignant histiocytosis and erythroleukaemia. In 1996, Cheong et al. (Hematology 1996; 1: 223) demonstrated the positive expression of EMA in monoblasts. Since there were very few useful markers for differentiating subtypes of acute myeloid leukaemia with a monocytic component from the those without, a study was conducted to evaluate the prevalence of EMA expression and its relationship with known markers for monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68) in monocytes and monoblasts.
METHODS: EMA detection was performed by flow cytometry in monocytes and monoblasts. EMA expression was compared with other known markers of monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68). Samples of purified monocytes were obtained from 20 healthy volunteers. Twenty-two cases of monocytic AML (M4 and M5) were studied and controls were selected from 20 cases of acute lymphoblastic leukaemia (ALL) and 18 cases of non-monocytic AML (M0, M1, M2, M3, and M7).
RESULTS: EMA was shown to be expressed strongly on the surface of all purified monocytes. EMA expression was observed on blast cells in 18/22 (81.8%) cases of AML M4 and M5, but not in that of non-monocytic AML or ALL. In this study EMA monoclonal antibody has demonstrated a strong association (P<0.001) with all the other known markers of monocytic-macrophage lineage in acute leukaemia subtypes. EMA had also shown 100% specificity and 81.8% sensitivity in the diagnosis of AML M4 and M5.
CONCLUSIONS: The monoclonal antibody EMA (clone E29) is a useful marker in the classification of acute myeloid leukaemia and can be used as a supplementary analysis for the diagnosis of acute leukemia with monocytic involvement.

Matched MeSH terms: Immunophenotyping
Fulltext Nasal and nasal-type natural killer (NK)/T-cell lymphoma: immunophenotype and Epstein-Barr virus (EBV) association

Peh SC, Danielle Quen QW

Med J Malaysia, 2003 Jun;58(2):196-204.
PMID: 14569739

Epstein-Barr virus (EBV) is believed to have a pathogenic role in lymphomas of the upper-aerodigestive tract. This study aims to elucidate the virus association pattern in nasal and nasal-type NK/T-cell lymphomas, and in sequential biopsies of these tumours. A total of 31 cases of previously diagnosed as lethal midline granuloma. Stewart's granuloma, nasal T-cell non-Hodgkin's lymphoma (T-NHL) and NK/T-cell lymphomas from all anatomical sites were retrieved from the files for the study. Reviews of these cases confirm 8 nasal T-NHL, 19 nasal and 4 extranasal lymphomas of NK/T-cell phenotype from 10 Malays, 18 Chinese, 2 Indian and 1 Kadazan. The male: female ratio was 2.4: 1. All T- and NK/T-cell lymphomas strongly expressed TIA-1 and 63% expressed CD2. The majority of NK/T-cell lymphoma occurred in Chinese (13/23), of which 12/13 (92%) of these cases were associated with EBV. Of the 15 nasal and 9 tonsillar B-cell lymphomas included for a comparison study, only 3 (20%) of the nasal cases were associated with EBV (1 male Chinese, 1 female Chinese and 1 male of other ethnic group). Eight cases of NK/T-cell tumours with sequential biopsies show persistence of EBV, irrespective of the interval and sites of subsequent presentations. This study confirms the cytotoxic nature of NK/T-cell tumour and that EBV is strongly associated with the disease regardless of the anatomical site of presentation and ethnicity. However, nasal and paranasal lymphomas of all phenotypes appear to show higher predilection of EBV association in the ethnic Chinese when compared to non-Chinese.

Matched MeSH terms: Immunophenotyping
Fulltext The immunophenotypic patterns of follicle centre and mantle zone in Castleman's disease

Peh SC, Shaminie J, Poppema S, Kim LH

Singapore Med J, 2003 Apr;44(4):185-91.
PMID: 12952030

Castleman's disease is an uncommon disease and the histopathogenesis is poorly understood. This study aims to investigate their clinicopathological and immunophenotypic profile.

Matched MeSH terms: Immunophenotyping*
Fulltext Sézary syndrome in a Malay--case report and literature review

Yuen P, Chan HL, Lee YS

Singapore Med J, 2001 May;42(5):224-7.
PMID: 11513062

Sézary syndrome is a rare form of primary cutaneous T cell lymphoma. It is a distinct systemic variant of mycosis fungoides, marked by erythroderma, lymphadenopathy and circulating cerebriform lymphocytes in the peripheral blood. We report a case of Sézary syndrome in a 61-year-old Malay man with a five-year history of indurated plaques, ulcers and tumours on the head and trunk, with characteristic findings on physical examination, skin biopsy, electron microscopy, immunophenotyping and peripheral blood film. A literature review on Sézary syndrome is presented.

Matched MeSH terms: Immunophenotyping
Clinical features and treatment outcome of children with myeloid antigen coexpression in B-lineage acute lymphoblastic leukemia: a study of 151 Malaysian children

Ng SM, Ariffin WA, Lin HP, Chan LL, Chin YM

J Trop Pediatr, 2000 Apr;46(2):73-8.
PMID: 10822932

The purpose of the study was to evaluate the incidence of myeloid antigen coexpression and its prognostic significance in childhood acute lymphoblastic leukemia (ALL) in Malaysia. A retrospective study was conducted of all ALL cases (< or = 12 years old) diagnosed and treated in University Hospital, Kuala Lumpur, Malaysia between 1 January 1992 and 30 May 1995, with available immunophenotype data. Presenting features and treatment outcome of 39 B-lineage ALL patients with myeloid antigen coexpression (My+B) were compared with 112 B-lineage ALL patients without myeloid antigen coexpression (My-B) for similarity in demographic, clinical and laboratory features and their treatment outcome. My+B and My-B patients were treated with a uniform treatment protocol. Myeloid antigen coexpression was defined as more than 30% isolated leukemic cells positive for CD13 and/or CD33. The ages at diagnoses ranged from 2 months to 12 years. Median age was 4 years. The incidence of myeloid antigen coexpression was 23 per cent. Univariate analyses showed that presenting features were similar between My+B and My-B with regard to age, sex, race, FAB morphology, white cell count, hemoglobin level, platelet count, liver/spleen size, central nervous system or mediastinal involvement, presence of lymphadenopathy, and proportion of blast cells detected in the marrow. Treatment outcome were not significant between the two groups. The 2-year event free survival was achieved in 44 per cent of My+B and 57 per cent of My-B (p = 0.11). The 2-year overall survival rates were 62 per cent for My+B vs. 77 per cent for My-B (p = 0.08). This study demonstrates that myeloid antigen coexpression is fairly common and constitutes 23 per cent of childhood ALL within the Malaysian population and that it is not an adverse risk factor in childhood ALL.

Matched MeSH terms: Immunophenotyping
Immunophenotyping pediatric leukemias in Kelantan, Malaysia

Menon BS, Dasgupta A, Jackson N

Pediatr Hematol Oncol, 1998 Mar-Apr;15(2):175-8.
PMID: 9592844

This study reviewed the immunophenotyping results of children with acute leukemia in Kelantan, Malaysia. In the 3.5-year period (January 1994 to June 1997), 45 cases were identified. All children were under the age of 12 years and the predominant ethnic group was Malay. Thirty-six cases (80%) were acute lymphoblastic leukemia (ALL) and 9 cases (20%) were acute myeloblastic leukemia (AML). Of the ALL cases, 3% were of B-cell and 22% of T-cell origin, and 96% of the B-lineage ALL were CD10 positive. All the AML cases expressed CD33 and 78% were positive for CD13. The incidence of mixed-lineage leukemias was 13.8% for My+ ALL and 11.1% for Ly+ AML.

Matched MeSH terms: Immunophenotyping*
Age- and sex-related changes in lymphocyte subpopulations of healthy Asian subjects: from birth to adulthood

Lee BW, Yap HK, Chew FT, Quah TC, Prabhakaran K, Chan GS, et al.

Cytometry, 1996 Mar 15;26(1):8-15.
PMID: 8809475

Flow cytometric analysis of lymphocyte subsets were evaluated in 391 healthy Asian subjects ranging in age from birth to 40 years. Lymphocyte subsets were analysed using specific monoclonal antibodies: CD20 (B cells), CD3 and CD2 (T cells), CD16 and CD56+ (NK cells), CD4/CD3+ (helper-inducer T cells), CD8/ CD3+ (suppressor/cytotoxic T cells), HLA-DR expression on CD3 and CD25 (Tac) on CD3. The total white cell count, absolute lymphocyte counts, and B cell percentages peaked in infancy and declined steadily with age. Absolute counts of each subset, which were derived from absolute lymphocyte counts, also followed this trend. Increases with age were seen in the NK, T cell (CD2, CD3), and CD8 percentages. Males tended to have higher NK and CD8 percentages than females, and, conversely, females had higher CD3 and CD4 percentages than males. Comparison of our results with studies involving Caucasian subjects indicated higher NK percentages in our Asian population and lower CD4 absolute counts in the males of our population. These results indicate the presence of age, sex, and probable racial differences in lymphocyte subset expression. Our results may serve as reference standards for the Asian population.

Matched MeSH terms: Immunophenotyping*
Fulltext Concordant childhood acute lymphoblastic leukemia in monozygotic twins

Chin YM, Wan Ariffin A, Lin HP, Chan YS

Med J Malaysia, 1996 Mar;51(1):145-8.
PMID: 10967997

Two 4-year-old monozygotic Chinese, female twins developed concordant childhood acute lymphoblastic leukemia (ALL) within an interval of about 2 weeks. Based on morphology and cytochemistry findings of the bone marrow blast cells, a diagnosis of ALL, L1 was made. Immunophenotyping showed the blast cells of both twins expressed similar antigens, i.e. HLA-DR, CD10, CD13, CD19, CD22 and CD34. Identical blood group, same HLA (human leucocyte antigen) genotype, sex and similar appearance suggest that the twins are monozygotic. Since the bone marrow leukemic cells of both twins were identical in morphology and expressed the same antigens with almost similar percentages of positivity, it is likely that the blast cells were derived from the same single clone. Based on the single clone hypothesis, the leukemogenic event must have arisen in utero in one twin and the cells from the abnormal clone then spread to the other twin via shared placental anastomoses.

Matched MeSH terms: Immunophenotyping
An immunohistochemical study of the lining epithelium of odontogenic keratocyst

Siar CH, Ng KH

J Nihon Univ Sch Dent, 1995 Sep;37(3):163-9.
PMID: 7490610

The lining epithelium of 15 cases of odontogenic keratocyst (OKC) was evaluated immunohistochemically. The peroxidase-antiperoxidase technique was applied to study the distribution of polyclonal keratin and S-100 protein while the indirect method was used to examine monoclonal vimentin and desmin reactivity. Consistent positive keratin staining was revealed in the lining epithelium of all 15 OKCs with additional intense staining in the stratum corneum. None of the cases showed vimentin or desmin reactivity within the lining epithelium elements. One of the 15 cysts studied showed positive S-100 protein staining in the nuclei of the lining epithelial cells. The pertinent literature on the immunophenotyping of the lining epithelium of OKC is reviewed.

Matched MeSH terms: Immunophenotyping
Fulltext Reference ranges for lymphocyte subsets in a defined Malaysian population

Dhaliwal JS, Balasubramaniam T, Quek CK, Gill HK, Nasuruddin BA

Singapore Med J, 1995 Jun;36(3):288-91.
PMID: 8553095

The aim of this study was to establish the lymphocyte subset reference ranges in a defined Malaysian population as well as to determine inter-racial differences for these values. Normal blood obtained from 152 subjects (55.9% Malay, 26.3% Chinese and 17.7% Indian) was immunophenotyped. Results obtained (expressed as mean +/- SD %), absolute count (x 10(6) cells/mm3) were as follows: CD3:66.5 +/- 8.6%, 2,066; CD4:33.2 +/- 8.5%, 1,028; CD831.6 +/- 8.9%, 982; CD19:12.0 +/- 0%, 5,374, and CD56+CD16:20.9 +/- 9%, 1,638. There were no significant differences between the percent lymphocyte subsets of the three racial groups. However, the absolute number of CD4 cells and CD19 cells in Chinese was significantly lower (p < 0.05) compared to the Indian and the Indian and Malay groups respectively. Comparison of our results with other reports showed that the percentage of Natural Killer cells in this population is higher than that reported for Caucasian population.

Matched MeSH terms: Immunophenotyping
Intracellular antigen determination by flow cytometry in leukaemic cells

Chin SF, Cheong SK

Malays J Pathol, 1994 Jun;16(1):69-73.
PMID: 16329579

Several fixation and permeabilization techniques that enable the flow cytometric analysis of the cell contents have been introduced in recent years. These methods allow sensitive detection of intracellular antigens that facilitates the diagnosis of certain diseases. We have undertaken in this study to evaluate a simple method of fixation and permeabilization using 2% paraformaldehyde and Tween 20. Intracellular antigens in three different leukaemia cases were analysed. We found that the method was reliable and easy. Intracellular kappa light chains were found in abundance in a case of plasma cell leukaemia. CD3 and CD22 were found in greater amount intracellularly than on the surface in pre-T-ALL and pre-pre B-ALL respectively.

Matched MeSH terms: Immunophenotyping/methods*
Immunophenotyping of peroxidase-negative acute leukaemias using immunoalkaline phosphatase (APAAP) method

Cheong SK, Lim YC, Ainoon O, Hamidah NH

Malays J Pathol, 1991 Dec;13(2):119-21.
PMID: 1823093

Immunophenotyping of acute leukaemias has become an important diagnostic tool in haematology laboratories as it is now well recognised that the presence of certain surface markers has prognostic significance. In 1988, we experimented with the alkaline phosphatase anti-alkaline phosphatase (APAAP) method for immunophenotyping of leukaemic cells in our laboratory. 48 cases of peroxidase-negative acute leukaemias were studied. Our study showed that 2 peroxidase-negative cases carried myeloid surface markers, 44% were negative for the markers studied and 5% were unclassified due to technical problems. We concluded that the APAAP method is a useful technique for demonstrating cell markers in leukaemic cells as the reaction is reddish and usually intense. We failed to demonstrate surface markers in 44% of the cases probably because of the choice of a limited panel of monoclonal antibodies.

Matched MeSH terms: Immunophenotyping/methods*
The spectrum of lymphoma in Malaysia: a histopathological study utilizing immunophenotyping

Mancer K

Malays J Pathol, 1990 Dec;12(2):77-88.
PMID: 2102968

A retrospective study was made to determine relative incidence of lymphoma subtypes in Malaysia. High grade non-Hodgkin's lymphoma was found to be common. Low grade non-Hodgkin's lymphoma and Hodgkin's disease were relatively rare in this Malaysian series. Non-Hodgkin's lymphoma of B-cell immunophenotype was four times as common as that of T-cell lineage. There was a high incidence of primary extranodal non-Hodgkin's lymphoma.

Matched MeSH terms: Immunophenotyping*