Analysis of β -thalassemia mutations in Guizhou Province / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the spectrum of β -thalassemia mutations in Guizhou Province.</p><p><b>METHODS</b>For 542 individuals suspected to have β -thalassemia by decreased mean corpuscular volume (MCV) and corpuscle hemoglobin (MCH) by routine blood test and hemoglobin electrophoresis, reverse dot blot hybridization (RDB) was performed to detect 17 known β -thalassemia mutations, including 8 common and 9 rare mutations. For cases where no mutation was identified, the entire human β -globin gene was screened to find other rare mutations. The distribution and frequencies of detected β -thalassemia mutations were then analyzed.</p><p><b>RESULTS</b>A total of 460 individuals were diagnosed as β -thalassemia by DNA analysis, which included 352 heterozygotes, 67 compound heterozygotes and 41 mutant homozygotes. A total of 12 β -thalassemia mutations were detected in these individuals. The mutations have ranked from high to low frequency as: CD17 (40.74%), CD41-42 (33.69%), IVS-II-654 (13.76%), -28 (3.70%), β E (3.35%), CD71-72(1.94%), CD43 (1.06%), IVS-I-1 (0.71%), CD27-28 (0.35%), -29(0.35%), CAP (0.18%), and CD121 (0.18%). The former six mutations have accounted for 97.18% of all. CD121 (GAA> TAA) detected from a heterozygote, as a dominant mutation, has been firstly found in the Chinese population.</p><p><b>CONCLUSION</b>The spectrum of β -thalassemia in Guizhou Province showed certain distinct characteristics, with CD17 being the most common mutation. The newly discovered mutation of CD121 has expanded the spectrum of β -thalassemia in Chinese population. Our result may provide valuable information for the prevention and control of β -thalassemia in Guizhou.</p>

Type II enteropathy-associated T-cell lymphoma: a clinicopathologic study / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features, immunohistochemical findings, differential diagnosis and prognosis of type II enteropathy-associated T-cell lymphoma (EATL).</p><p><b>METHODS</b>Fourteen cases of type II EATL encountered in Department of Pathology, Nanjing General Hospital were retrospectively reviewed. The clinical data, histologic features, immunohistochemical findings and follow-up information were analyzed, with literature review.</p><p><b>RESULTS</b>There were altogether 12 males and 2 females. The median age of patient was 49 years. The sites of involvement included jejunum (10 cases) and ileum/colon (4 cases). The patients often presented with an abdominal mass, abdominal pain, diarrhea and constitutional symptoms such as fever, night sweating and cachexia. There was no clinical evidence of gluten-sensitive enteropathy. Histologically, the lymphoma cells showed full-thickness infiltration of the intestinal wall. They contained round hyperchromatic nuclei and pale cytoplasm. The stroma was minimally inflamed, with or without associated coagulative necrosis. A remarkable finding was the presence of villous atrophy, cryptal hyperplasia and intraepithelial lymphocytosis. Immunohistochemical study showed that the tumor cells expressed CD3, CD43 and CD8 (14/14). Some of them were also positive for CD56 (11/14) and CD30 (2/14). The staining for CD4, CD20, CD79a and myeloperoxidase was negative. A high proliferation index was demonstrated by Ki-67 immunostain. In-situ hybridization for EBER was negative. Follow-up data were available in 9 cases. The duration of follow-up ranged from 6 months to 36 months. Seven patients died within 14 months.</p><p><b>CONCLUSIONS</b>EATL is a rare type of lymphoma with intestinal involvement. Associated enteropathy is not demonstrated, in contrast to cases encountered in Nordic countries. A correct diagnosis requires evaluation of clinical manifestations, pathologic features and ancillary study results.</p>

Clinicopathologic features of intestinal natural killer/T-cell lymphoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features, diagnosis and differential diagnosis of intestinal natural killer (NK)/T-cell lymphoma.</p><p><b>METHODS</b>The clinical features, histopathology, immunohistochemical findings and follow-up data of 14 cases of intestinal NK/T-cell lymphoma were retrospectively reviewed.</p><p><b>RESULTS</b>The male-to-female ratio was 9:5. The medium age of patients was 45 years. The sites of involvement included small intestine (6 cases), colon (6 cases) or both (2 cases). The main clinical manifestations were an abdominal mass, other gastrointestinal symptoms such as abdominal pain, as well as systemic symptoms such as fever and cachexia. Intestinal perforation complicated by acute peritonitis might occur in advanced disease. Histologically, the intestinal wall showed full-thickness infiltration by medium-sized atypical lymphoid cells with pleomorphic nuclei, prominent inflammatory background, angiocentric/angiodestructive growth pattern and coagulative necrosis. Immunohistochemical study showed that the tumor cells were positive for CD3ε, CD43, CD56, granzyme B and perforin. They were negative for CD20, CD79α and MPO. In-situ hybridization for Epstein-Barr virus encoded RNA (EBER) showed negative signals. A high proliferative index was demonstrated by Ki-67 immunostaining. Follow-up data of 8 cases were available, with duration of follow up ranging from 0.5 to 36 months. Five patients died within 20 months.</p><p><b>CONCLUSIONS</b>Extranodal NK/T-cell lymphoma, nasal-type primarily involving intestine is rare and tends to carry an aggressive clinical course. The relatively non-specific clinical manifestations of intestinal NK/T-cell lymphoma may result in misdiagnosis in some cases. A comprehensive evaluation of clinical manifestations, pathologic features and immunohistochemical findings is essential for definitive diagnosis.</p>

Abnormal expression of CD43 in patients with systemic lupus erythematosus and its clinical significance / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Previous studies indicate that CD43 plays a role in regulating the adhesion of lymphocytes, cell mutation and activation, however, little is known about its effect on systemic lupus erythematosus (SLE). This study was designed to explore the clinical significance of CD43 in SLE patients.</p><p><b>METHODS</b>We used microarray and real-time PCR to detect the mRNA and protein expression of magnetic bead sorted T cells and B cells from peripheral blood mononuclear cells (PBMCs) of SLE patients, and analyzed the relationship between CD43 and the clinical indexes.</p><p><b>RESULTS</b>Both microarray and real-time PCR results showed that CD43 mRNA was significantly decreased in PBMCs of SLE patients compared with healthy controls (P < 0.001). There were no significant differences between lupus nephritis and non-lupus nephritis patients, and neuropsychiatric and non-neuropsychiatric patients. CD43 mRNA expression was significantly reduced in T cells but not in B-cells in SLE patients compared to healthy controls (P < 0.01). Compared with healthy controls, the percentage of CD43(+) cells in the PBMCs of SLE was significantly decreased (P = 0.004), and the CD43 fluorescence intensity in CD3(+)/CD43(+) cells and CD19(+)/CD43(+) cells was also significantly weaker than in healthy controls (P = 0.039 and 0.003). There was no significant difference in the percentage of CD3(+)/CD43(+) cells, CD19(+)/CD43(+) cells between the two groups. The CD43 fluorescence intensity in CD3(+)/CD43(+) cells was inversely correlated with the levels of IgG and IgM (r = -0.8 and -0.6).</p><p><b>CONCLUSIONS</b>Compared to healthy controls, both CD43 mRNA and protein expressions were reduced in T cells from patients with SLE, and were inversely correlated with IgG.</p>

Granulocytic sarcoma: a clinical and pathologic analysis of ten cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the clinical and pathological features, differential diagnosis of granulocytic sarcoma.</p><p><b>METHODS</b>The clinical manifestations, histopathological features, immunohistochemistry, treatment and prognosis were analyzed retrospectively in 10 cases of granulocytic sarcoma.</p><p><b>RESULTS</b>The age of patients ranged from 10 to 56 years (means = 35.8 years). The male-to-female ratio was 1.5:1. Histologically, the malignant cells of granulocytic sarcoma grew in a diffuse pattern. The cytoplasm was scanty, with eosinophilic fine granularity in some cells. The nuclei were round or focally irregular, and had finely dispersed chromatin. The mitotic figures were visible. Immunohistochemical stains for MPO, CD43, CD117, CD34 and CD99 were positive.</p><p><b>CONCLUSIONS</b>Granulocytic sarcoma can occur in patients of all ages with a male predominance. The diagnosis of granulocytic sarcoma is assisted by the cytochemical stain for naphthol-ASD-chloroacetate esterase and/or immunophenotypic analyses for MPO, CD43, CD117, CD34, CD99. These stains aid in the distinction of granulocytic sarcoma from: lymphoblastic lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma, small round cell tumours, particularly in children, and blastic plasmacytoid dendritic cell neoplasm.</p>

Differential expression of c-kit and CD43 in histological subtypes of adenoid cystic carcinoma of salivary gland

Adenoid cystic carcinoma [ACC] of the salivary gland is characterized by a prolonged but inevitably unfavorable clinical course. Recent studies have suggested that the transmembrane tyrosine kinase receptor, c-kit proto-oncogene is involved in ACC pathogenesis. CD43 is a sialogly-coprotein that is typically expressed by hematopoietic cells and their derivative neoplasms, although positivity in epithelial tumors has only been recognized recently. The aim of this study was to evaluate c-kit and CD43 immunoreactivity in ACCs and to compare the extent of their expression in various histologically defined subgroups of ACC, and their probable involvement in ACC pathogenesis. Formalin-fixed paraffin-embedded sections from 35 ACCs were immunostained for c-kit and CD43 using monoclonal antibodies. Cytoplasmic and membranous c-kit immunoreactivity was detected in 25/35 ACCs [71.4%] with strong immunostaining observed in solid pattern of ACC. Cytoplasmic and membranous CD43 immunoreactivity was detected in 18/35 [51.4%] of ACCs with strong immunostaining seen in the cribriform pattern. These results suggested that c-kit could be used as a prognostic marker for ACC and specific c-kit tyrosine kinase inhibitors such as imatinib, might be used in future therapeutic approaches against subgroups of ACC. CD43 appears to be preferentially expressed in salivary gland ACCs. Its expression decreased with cellular dedifferentiation and there was an inverse relationship between immunoexpression of c-kit and CD43 among ACC of salivary gland

Immunohistochemical expression of CD20, CD43, and CD79 in Burkitt's lymphoma

Burkitt's lymphoma was reported as a distinct clinicopathological entity, it is a malignant and lethal condition that affects children between 2 and 8 years of age presenting as a massive growth in one or both sides of the maxilla or the mandible, in the molar-premolar region with loosening of the deciduous teeth or with premature eruption of permanent teeth. This study aims to evaluate the immunohistochemical expression of CD20, CD43, and CD79 in Burkitt's Jaw Lymphoma in relation to clinicopathological findings. Seven children [6 boys and 1 girl] aged 4-6 years old who were examined at Department of Oral and Maxillofacial Surgery, College of Dentistry, Anbar University and were investigated to correlate between clinicopathological findings of Burkitt's lymphoma using histopathological examination including imprint cytology, H and E and immunohistochemical expression of CD20, CD43, and CD79. The maxilla involved in all cases, the mandible in 2 cases, while the abdomen and viscera involved in 1 case only. The tumor cells showed lymphoblastic cells, with a uniform degree in cell size and cell maturity, darkly stained due to high content of ribonucleic acid [RNA] and cytoplasmic vacuoles due to high content of lipid and under light microscope; the tumor composed of small round cells interspersed with histocyte as starry sky appearance; while Immunohistochemical expression was done by evaluation of CD20, CD43, and CD79 expressions; The immunohistochemical staining using CD20, CD43, andCD79 monoclonal antibodies is a principal laboratory aids has a considerable value in the diagnosis and characterization of Burkitt's lymphoma, and they provide critical information for guiding clinicians to the appropriate treatment protocol for these malignancies

Clinicopathologic features of granulocytic sarcoma: a study of 38 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features of granulocytic sarcoma.</p><p><b>METHODS</b>The clinical and pathologic findings of 38 cases of granulocytic sarcoma were retrospectively analyzed. Immunohistochemical study was performed and the literature was reviewed.</p><p><b>RESULTS</b>The age of patients ranged from 2 to 77 years (mean = 43.3 years). The male-to-female ratio was 1.5:1. Major clinical presentations included superficial lymph node enlargement and painful soft tissue mass. Follow-up data were available in 18 patients; and 14 of them died of tumor-related diseases. The average duration of survival of the patients was 16.9 months. Histologically, the tumor cells were relatively uniform in appearance and small to medium in size. The cytoplasm was scanty and pale in color. The nuclei were round or focally irregular, with fine chromatin and inconspicuous nucleoli. Mitosis figures were readily identified. Scattered immature eosinophilic myelocytes were seen. Immunohistochemical study showed that the tumor cells in all cases expressed MPO and CD43. Most cases were also positive for CD68, lysozyme, CD99 and TdT. The staining for CD3, CD20, CD79a, pan-cytokeratin and PLAP were negative.</p><p><b>CONCLUSIONS</b>Granulocytic sarcoma is a known histologic mimicker of non-Hodgkin lymphoma, Ewing sarcoma/PNET and embryonal rhabdomyosarcoma. Detailed morphologic examination, when coupled with immunohistochemical study, is useful in arriving at a correct diagnosis.</p>

Small cell variant of peripheral T-cell lymphoma, not otherwise specified: a clinicopathologic and immunophenotypic analysis / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features and differential diagnosis of small cell variant of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS).</p><p><b>METHODS</b>The clinicopathologic features of 5 cases of small cell variant of PTCL, NOS were retrospectively reviewed, with immunohistochemical study, T-cell receptor (TCR) gene rearrangement analysis and evaluation for Epstein-Barr virus (EBV) status.</p><p><b>RESULTS</b>All the 5 patients were males. The mean age was 52.6 years. The median duration before diagnosis was 1 month. Clinically, 3 patients presented in stage IV and 2 in stage III. Four of them had generalized lymphadenopathy and splenomegaly. Hepatomegaly and massive effusion were found in 1 and 2 cases, respectively. Marrow involvement was detected in 3 of the 4 patients with bone marrow biopsy performed and one of them also accompanied by lymphocytosis. Histologically, the involved lymph nodes showed partial or complete effacement of nodal architecture and replacement by a monomorphous population of small lymphoid cells. Scanty large lymphoid cells were also identified in 4 cases. Increase in number of blood vessels was noticed in two of them as well. Immunohistochemically, the lymphoma cells in all cases expressed two or more of the T-cell markers and CD43. The staining for CD20, TdT, CD56 and granzyme B was negative. CD99 expression was noted in 3 of the 4 cases. The Ki-67 index ranged from 5% to 15%. Clonal TCRgamma gene rearrangement was detected in the 4 cases studied and one of them also showed TCRbeta gene rearrangement. In-situ hybridization for EBV-encoded RNA was negative in the 4 cases studied. Follow up information was available in 3 of the 5 cases. All of the 3 patients died of the disease, with an average survival of 21.7 months.</p><p><b>CONCLUSION</b>Small cell variant of PTCL, NOS represents a rare disease entity which often presents in advanced tumor stage and carries a poor prognosis.</p>

A clinicopathologic study of mantle cell lymphoma in a single center study in India.

We present clinical features, histopathology and results of treatment in cases of mantle cell lymphoma (MCL) at our hospital. We had 93 cases (2.1%) of MCL out of total 4301 cases of non-Hodgkin's lymphoma (NHL) in a 4-year period. It included 68 cases (1.7%) of MCL from 3987 cases of NHL diagnosed on histopathology. Remaining 25 cases (7.9%) diagnosed solely on peripheral blood examination were excluded. Thirty-six (85%) patients had advanced-stage disease. Sixty-three were nodal and five were extranodal (all gastrointestinal tract). Common patterns were diffuse (64%), nodular (25%) and mantle zone type (11%). Sixty-two cases had lymphocytic while six had blastic morphology (all nodal). Tumor cells expressed CD20 (100%), CD43 (94%), CD5 (89%) and cyclin D1 (85%). Bone marrow was involved in 25 (59%) cases. Thirty-two patients could be treated. Median recurrence-free survival was 22.23 months. Diffuse pattern of nodal involvement had a lower overall survival.

Granulocytic sarcoma of breast: an aleukemic presentation.

Granulocytic sarcoma is a rare extramedullary tumor composed of immature myeloid cells. It is usually associated with leukemia or other myeloproliferative disorders but can also occur without overt hematologic diseases. The breast is an uncommon site of presentation and requires a high index of suspicion for diagnosis. We report such a case in a 45-year-old female, who presented with nontender left breast lump of 6 months' duration. A peripheral smear and bone marrow examination at that time was normal. A lumpectomy was done. An H and E diagnosis of lobular carcinoma vs. non-Hodgkin's lymphoma was entertained. Immunostains, however, revealed myeloperoxidase, naphthol AS-D chloroacetate esterase and CD43 positivity, indicating a diagnosis of granulocytic sarcoma. It appears that early initiation of systemic AML-type chemotherapy is beneficial and may delay or avert the development of AML in bone marrow and blood. Eight months later, the patient presented with an orbital mass; bone marrow and peripheral smear involvement by AML.

Skin lesions and myelodysplastic syndrome as initial manifestations of biphenotypic acute leukemia / 中国实验血液学杂志

The aim of this study was to investigate the clinical, pathological and biological features of biphenotypic acute leukemia. The morphology of tumor cells was observed by bone marrow examination; the immunophenotype was assayed by flow cytometry and immunohistochemistry; the chromosomal aberrations were detected by conventional chromosomal analysis and RT-multiplex nested PCR. The results showed that extramedullary skin lesions and myelodysplasia occurred before the onset of overt disease. At the time of diagnosis, this case had more than 30% blasts in bone marrow with meningeal involvement. Large-sized tumor cells predominated morphologically over other cells. Flow cytometry revealed the co-expression of myeloid antigens (cMPO, CD33 and CD117) and T-lymphoid antigens (cCD3, CD5, CD7, dual expression of CD4 and CD8). Immunohistochemical staining showed that CD43 and CD99 were strong positive which define the earliest hematopoietic progenitors. Partial tandem duplication of the MLL gene could be detected with normal cytogenetic method. All above-mentioned results led to the diagnosis of biphenotypic acute leukemia. It is concluded that the biphenotypic acute leukemia is an uncommon type of leukemia which may be preceded by myelodysplastic syndrome and has aggressive clinical and biological behavior. Immunophenotype, cytogenetics and molecular analysis can contribute to early diagnosis of BAL and evaluation of prognosis.

CD43 cross-linking increases the Fas-induced apoptosis through induction of Fas aggregation in Jurkat T-cells

CD43 (sialophorin, leukosialin) is a heavily sialylated surface protein expressed on most leukocytes and platelets including T cells. Although CD43 antigen is known to have multiple and complex structure, exact function of CD43 in each cell type is not completely understood. Here we evaluated the role of CD43 in Fas (CD95)-induced cell death in human T lymphoblastoid cell line, Jurkat. Crosslinking CD43 antigen by K06 mAb increased the Fas-mediated Jurkat cell apoptosis and the augmentation was inhibited by treatment with caspase inhibitors. Further, CD43 signaling of Jurkat cells induced Fas oligomerization on the cell surfaces implying that CD43 ligation have effects on early stage of Fas-induced T cell death. These also suggest that CD43 might play an important role in contraction of the immune response by promotion of Fas-induced apoptosis in human T cells.

Clinicopathologic and immunophenotypic analysis of myeloid sarcoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features of myeloid sarcoma and to evaluate the role of immunohistochemical study in diagnosis of this entity.</p><p><b>METHODS</b>Eighty-two cases of myeloid sarcoma were retrieved from the archives of Department of Pathology, West China Hospital of Sichuan University during the period from January, 1990 to February, 2005. The morphologic features were reviewed and classified according to the 2001 WHO classification for hematopoietic and lymphoid tissue tumors. Immunohistochemical study using a panel of 11 antibodies was performed on 73 cases. The survival data were collected and analyzed by SPSS 10.0.</p><p><b>RESULTS</b>The median age of patients was 35.5 years. The male-to-female ratio was 1.4:1. The sites of occurrence included lymph node (43.1%), skin (16.7%), nose (7.8%), soft tissue (7.8%) and bone (6.9%). Fifty-one cases (62.2%) represented myeloid sarcoma associated with an underlying myeloproliferative disorder and 25 cases (30.5%) represented solitary myeloid sarcoma. As for the morphology, 79 cases (96.3%) were granulocytic sarcoma, including 41 cases (51.9%) blastic type, 25 cases (31.6%) immature type and 13 cases (16.5%) differentiated type. The other 3 cases (3.7%) were monoblastic sarcoma. Immature eosinophils were found in 51 cases (64.6%) of granulocytic sarcoma, among which 13 cases (31.7%) were of blastic type. Immunohistochemical study showed that 95.9% cases (70/73) were positive for myeloperoxidase, 95.5% (63/66) for lysozyme, 95.2% (60/63) for CD68 (KP1), 90.8% (59/65) for leukocyte common antigen, 85.7% (54/63) for CD43, 77.8% (49/63) for CD117, 58.7% (37/63) for CD99, 54.0% (34/63) for CD15, 22.2% (14/63) for CD34, and 4.7% (3/64) for CD68 (PG-M1). Proliferation index, as demonstrated by Ki-67 positivity, was 0.49+/-0.22. Follow-up data was obtained in 59 of the 82 patients. The two- and five-year survival rates were 36.1% and 17.3% respectively. No significant prognostic factors were found in the survival analysis.</p><p><b>CONCLUSIONS</b>Myeloid sarcoma may precede, develop in a background of myeloproliferative disorder or even after remission of the disease. The presence of immature eosinophils is an important morphologic clue and immunohistochemical study plays an essential role in arriving at a correct diagnosis. Immunopositivity for myeloperoxidase is specific for granulocytic differentiation, while CD68 (PG-M1)-positivity suggests monocytic differentiation. Detailed clinicopathologic correlation is also helpful.</p>

Clinicopathologic study of 369 B-cell non-Hodgkin lymphoma cases, with reference to the 2001 World Health Organization classification of lymphoid neoplasms / 中华病理学杂志

<p><b>OBJECTIVE</b>To describe the relative frequency, morphologic features, immunophenotype and clinical data of different types of B-cell non-Hodgkin lymphoma (B-NHL) and to evaluate the practical application of the 2001 World Health Organization (WHO) classification of lymphoid neoplasms.</p><p><b>METHODS</b>369 documented cases of B-NHL were further subtyped according to the 2001 WHO classification of lymphoid neoplasms, on the basis of hematoxylin and eosin staining, immunohistochemistry and in-situ hybridization techniques.</p><p><b>RESULTS</b>Amongst the 369 cases of B-NHL studied, 353 cases could be further classified into 11 subtypes. Diffuse large B-cell lymphoma, extranodal marginal zone lymphoma and follicular lymphoma were the commonest subtypes, accounting for 51.2% (189 cases), 14.9% (55 cases) and 10.6% (39 cases) of all cases respectively. Tumors in lymph nodes were seen in 158 cases (42.8%) and in extra node in 211 cases (57.2%). B-cell prolymphocytic leukemia and hairy cell leukemia were not identified. When comparing the diagnosis based on morphologic examination alone with the diagnosis based on both morphology and immunophenotype, there was a 80% concordance rate. Immunohistochemical study was helpful in reaching the correct diagnosis in many cases and could improve the overall diagnostic accuracy by about 20%.</p><p><b>CONCLUSIONS</b>Amongst cases of B-NHL, diffuse large B-cell lymphoma is the commonest subtype, followed by MALToma and follicular lymphoma. While morphologic examination forms the basis for lymphoma diagnosis, immunohistochemical study also plays an important role in further subtyping. A combination of both modalities are sufficient for arriving at an accurate diagnosis in most cases of B-NHL, in keeping with the recommendation of the 2001 WHO classification of lymphoid neoplasms.</p>

Expression of CD43 in Colorectal Adenocarcinom

BACKGROUND: CD43 is a sialoglycoprotein that is highly expressed on most leukocytes, except on B lymphocytes and dendritic cells. CD43 has been reported to be involved in the adhesion and apoptosis of lymphocytes. Although the aberrant expression of CD43 antigen in non-lymphoid tissues has been reported, the expression of the CD43 antigen in gastrointestinal malignancies is not well studied. Here, we studied the expression of CD43 in colon adenocarcinoma using the anti-CD43 monoclonal antibody developed in our laboratory. METHODS: Thirty patients who had undergone surgical resection for colorectal carcinoma were recruited. The expression of CD43 molecule was determined by analyzing the formalin-fixed, paraffin-embedded specimens immunohistochemically using our newly developed anti-CD43 mAb (K06). The results obtained by the immunohistochemical analysis correlated to the clinicopatho-logical parameters. RESULTS: The expression of CD43 were found in 20 out of 30 colorectal carcinoma cases. The expression of CD43 antigen is higher in well differentiated adenocarcinomas than poorly or moderately differentiated adenocarcinomas. CONCLUSIONS: The new anti-CD43 mAb might be helpful for the detection of the expression of CD43 on colorectal carcinoma cells. Further studies are required to assess the relationship between the CD43 expression and the colorectal carcinogenesis.