Expression of a new human THY-1 related antigen in Ewing's sarcoma and peripheral neuroectodermal tumors

Ewing's sarcoma (ES), peripheral neuroectodermal tumor (PNET) and Askin's tumor of the chest wall share a reciprocal chromosomal translocation between the long arms of chromosomes 11 and 22 (q23-24; q12). In the absence of other distinguishing features this specific translocation is regarded as marker of a common and neuroectodermal origin for these rare tumors. A monoclonal antibody (HBA-71) developed in our laboratory has been found to recognize an unique ES and PNET associated antigen, which is also expressed in some normal tissues, including thymus, bone marrow, islets of Langerhans, ependyma and adenohypophysis. It is shown in this study that this HBA-71 antigen is closely related to the murine THY-1 antigens, major cell surface glycoproteins of thymocytes and brain in mice and rat. Both antigens have similar molecular ratios (18,000), amino acid compositions and sensitivity to tryptic digestion, show high cell surface expression, and binding of the appropriate antibodies to HBA-71 antigen triggers proliferation in thymocytes. The HBA-71 epitope may represent a primitive neuroectodermal marker of ES/PNET, or its expression may be directly linked to the reciprocal translocation invariably associated with HBA-71-positive ES and PNET tumors, which maps to the same region of chromosome 11 (q23-24) as the human Thy-1 gene.     

Expression of CD56 (NKH-1) differentiation antigen in human thyroid epithelium.

Leu-19 (CD56) MoAb is well known to recognize gp220 expressed on natural killer (NK) cells and is widely used as a NK cell marker. The expression of CD56 antigen was tested by means of sensitive alkaline phosphatase-anti-alkaline phosphatase (APAAP) immunohistochemical technique and the above mentioned MoAb as a primary antibody, on frozen sections of various fresh human tissues. Out of 11 organs examined only thyroid gland provided a distinct reaction confined to cell membranes of epithelial follicular cells. The reaction had a diffuse pattern in cases of Graves' disease and colloidal goitre while in Hashimoto's thyroiditis presented as a focal pattern. Other anti-NK cell MoAbs such as VD4 (CD16) and Leu-7 (CD57) reacted only with single cells of thyroid stroma. The results of APAAP staining were confirmed by the cytofluorimetric assessment of isolated thyroid cells. It is speculated that CD56 expression on thyroid cells may have a functional significance, perhaps related to neural-endocrine interactions.     

Proliferating cell nuclear antigen and S phase fraction in endometrial stromal sarcoma.

AIMS: To investigate the value of immunohistochemical staining for the cell cycle protein proliferating cell nuclear antigen (PCNA) and flow cytometric S phase fraction in determining prognosis in endometrial stromal sarcoma, graded according to mitotic count. METHODS: Seventeen endometrial stromal sarcomas from 13 patients treated at the Royal Marsden Hospital were analysed. Serial 5 microns sections were cut for haematoxylin and eosin and immunohistochemical staining for PCNA, performed using the murine monoclonal antibody PC10. PCNA positivity was expressed as a percentage of the total number of cells (PCNA index). Flow cytometric analysis was performed on nuclei extracted from paraffin wax sections. RESULTS: In the five patients who died of disease within five years, PCNA index varied between < 1% and 60% (mean 21%) and S phase fraction ranged from 11.3 and 20.1 (mean 13.8). Four patients who were apparently cured showed PCNA indices ranging from < 1% to 5% (mean 1.75%) and S phase fraction ranging from 1.4 to 3.5 (mean 2.3); and three patients alive with disease showed PCNA indices ranging from 1% to 15% (mean 8.6%) and S phase fraction ranging from 1.4 to 3.5 (mean 2.3). One patient who died from indolent local disease after nine years showed a PCNA of 1 or less and an S phase fraction of 0.9. CONCLUSIONS: PCNA staining was variable and therefore not a reliable prognostic indicator, but a high PCNA index was only found in those patients dying of disease within five years. A stronger association was seen between S phase fraction and prognosis; this also correlated well with histological grade determined by mitotic count. In individual borderline cases that are between low and high grade categories, these procedures may be useful.     

Seroepidemiology of human bocavirus in Apulia,Italy

A serological survey was performed to determine the prevalence of antibodies against human bocavirus in an Apulian population. Anti-hBoV IgG antibodies were analysed in 1206 inhabitants (age range, 1 month–84 years) using a standardized ELISA test based on the use of recombinant hBoV VP2 virus-like particles. In total, 1075 (89.1%) of 1206 participants (mean age 32 ± 24.8 years) displayed anti-hBoV-IgG. The seroprevalence increased significantly (p < 0.0001) in children from 2–4 years (64.2%) to 5–9 years (96.4%). A similar trend was observed in both male and female subjects. In conclusion, our results show that hBoV infection is common in this population, especially in children.     

Seroepidemiology of human parvovirus B19 in Taiwan

In order to determine the prevalence and risk factors of human parvovirus B19 (B19) infection in Taiwan, a seroepidemiological study was carried out in 19 townships. Serum samples were collected from 862 healthy residents, who were selected by stratified random sampling from various study areas. They were chosen from four different ethnic groups including aborigines, Fukien Taiwanese, Hakka Taiwanese, and mainland Chinese. Serum samples were screened for B19 IgG antibody by indirect antibody capture enzyme-linked immunosorbent assay (ELISA) and B19 IgM by IgM antibody capture (MAC)-ELISA, respectively. The overall prevalence of anti-B19 IgG and anti-B19 IgM was 32.8% and 0.35%, respectively. The anti-B19 seropositive rate in females was significantly higher than that of males (36.4% vs. 29.4%, P < .001). The age-sex-adjusted seropositive rate in urban townships (39.9%) was higher than that in aboriginal townships (30.5%, P < .001). The seropositive rate increased significantly with age showing a dose–response relationship (P = 0.0001 based on a trend test). Blood transfusion was found to be associated with an increased seropositive rate showing a multivariate-adjusted odds ratios of 1.6. J. Med. Virol. 57:169–173, 1999. © 1999 Wiley-Liss, Inc.     

Cross-linking of the CAMPATH-1 antigen (CD52) triggers activation of normal human T lymphocytes

The CAMPATH-1 (CD52) antigen is a 21–28 kDa glycopeptidewhich is highly expressed on lymphocytes and macrophages andis coupled to the membrane by a glycosylphosphatidylinositol(GPI) anchoring structure. The function of this molecule isunknown. However, it is an extremely good target for complement-mediatedattack and antibody-mediated cellular cytotoxicity. The humanizedCAMPATH-1H antibody, which is directed against CD52, is veryefficient at mediating lymphocyte depletion in vivo, and iscurrently being used in clinical trials for lymphoid malignancyand rheumatoid arthritis. It is therefore important to examinethe functional effects of this antibody on different lymphocytesub-populations. Because several other GPI-linked moleculesexpressed on the surface of T lymphocytes are capable of signaltransductlon resulting in cell proliferation, we have investigatedwhether the CAMPATH-1 antigen can also mediate these effects.In the presence of phorbol esters and cross-linking anti-lgantibodies, mAbs specific for CD52 induced proliferation andlymphokine production in highly purified resting CD4⁺ and CD8⁺T lymphocytes. The ret lgG2c YTH 361.10 anti-CD52 antibody,however, was able to activate resting CD4⁺ and CD8⁺ T cellsdirectly without cross-linking or phorbol myristate acetatein the absence of Fc-bearlng cells. Anti-CD52 antibodies alsoaugmented the anti-CD3 mediated proliferatlve response of CD4⁺and CD8⁺ T cells when the two antibodies were co-immobilizedonto the same surface or cross-linked in solution by the samesecond antibody. Both CD4⁺CD45RA and CD4⁺CD45RO T cells werestimulated to proliferate by anti-CD52 antibodies in the presenceof appropriate co-stimulatory factors. Antl-CD52 mAbs did not,however, synerglze with anti-CD2 or CD28 mAb to induce CD4⁺T cell proliferation. The activation of CD4⁺ T cells by antl-CD52antibodies was inhibited by cyclosporin A, suggesting a rolefor the calcineurin-dependent signal transduction pathways.Although CD52 could transduce a signal In T cells, anti-CD52antibodies did not inhibit antigen-specific or polyclonal Tcell responses, suggesting this molecule does not play an essentialco-stimulatory role in normal T cell activation.     

Monoclonal antibody (F5) to human prostate antigen

Hybridoma culture F5 has been developed which secretes monoclonal antibody (McAb) directed to an epitope of a prostatic glycoprotein of Mr 34 kD (Prostate Antigen, PA). Tissue levels of PA have been evaluated using a competitive-binding enzyme-immunoassay based upon the inhibition of McAb binding activity to purified antigen. Results indicated the specific occurrence of high antigen concentrations in extracts prepared from prostatic tissues. The antigenicity of epitope F5 is resistant to tissue fixation and embedding protocols, and has been demonstrated upon immunoperoxidase staining procedures. Immunoperoxidase data strongly indicate that McAb F5 possesses a singular specificity towards prostatic epithelial cells. Other tissues, whether normal or cancerous, fail to express this determinant. Specimens examined included epithelial and nonepithelial tissues along with a panel of carcinomas and sarcomas. The antibody was able to detect tumor cells at extra-prostatic sites and represents a powerful probe for the detection and differential diagnosis of metastatic cancer of the prostate.     

Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus

The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation indexes of greater than or equal to 2.00 to productively infected antigens had stimulation indexes of less than or equal to 2.00 to early antigens. Viral polypeptides with molecular weights of 83,000, 72,000, 62,000, 56,000, and 40,000 were identified in early antigen preparations.     

Generic human leukocyte antigen class II (DRB1 and DQB1) alleles in patients with paracoccidioidomycosis.

Human leukocyte antigen (HLA) class II alleles are involved in antigen processing and in the presentation of antigens to T lymphocytes. Few studies have investigated HLA genes in paracoccidioidomycosis. In the present investigation, we analyzed the distribution of the HLA class II alleles DRB1 and DQB1 in 45 healthy volunteers and in 80 patients with paracoccidioidomycosis. The patients presented with various clinical forms of the disease, and allele distribution was evaluated individually in each presentation type. In patients with the unifocal chronic form of the disease, a mild clinical presentation in which lesions are restricted or localized, the HLA allele most commonly seen was DRB1*11 (p<0.039). This suggests that the participation of HLA antigens may influence the outcome of the host-parasite interaction in paracoccidioidomycosis, regulating the immune response to Paracoccidioides brasiliensis antigens.     

Immunohistochemical detection of the human herpes virus 8 (HHV8) latent nuclear antigen-1 in Kaposi's sarcoma

AIMS: The molecular genetics of the human herpes virus 8 (HHV8) has now been characterised and the virus appears to be important in the pathogenesis of Kaposi's sarcoma (KS). This study attempts to determine the rate of HHV8 infection in KS in an Australian cohort. METHODS: Routine streptavidin-biotin-peroxidase immunostaining with diaminobenzidine was performed on paraffin-embedded archival tissues of 37 KS cases using a murine monoclonal antibody directed against the C-terminus of the latent nuclear antigen-1 molecule of HHV8 (clone 13B10; Novocastra) at 1:50 dilution. RESULTS: Positive HHV8 nuclear staining was detected in the nuclei of the spindle cells and endothelial cells of the vascular channels in about 78% (29/37) of all cases. HHV8 staining was absent in the non-neoplastic vessels in the adjacent tissue (P=0.0001, chi(2)=44.46; chi(2)-test with continuity correction) and the negative control cases of Merkel cell carcinoma (P=0.02, chi(2)=5.07; chi(2)-test with continuity correction). HHV8 staining was detected in 80% (8/10 cases) of the patch stage, 88% (7/8 cases) of the plaque stage and 74% (14/19 cases) of the late stage. No significant difference was found between HHV8 positivity and HIV status, age, gender, tumour recurrence, multiplicity or site of the lesions. CONCLUSIONS: The latent nuclear antigen-1 of HHV8 can be detected by immunohistochemistry in the majority of human KS lesions, raising the possibility of its future potential use as an adjunct for the diagnosis of KS in problematic cases.     

Seroepidemiology of group I human coronaviruses in children.

BACKGROUND: Recently, several new human coronaviruses have been identified. OBJECTIVES: To define the seroepidemiology of group I human coronaviruses. STUDY DESIGN: A recombinant protein enzyme linked immunosorbent assay (ELISA) based on portions of the nucleocapsid protein of group I human coronaviruses was developed and was used to screen serum from 243 children and young adults. RESULTS: For HCoV-229E, the percentages of seropositive individuals were 57.1% for infants <2 months old; 38.9% for infants 2-3 months old; 4.7% for infants 4-5 months old; 42.9-50.0% for infants 6-12 months old; 34.8-62.5% for individuals 1-20 years old. For HCoV-NL63, the percentages of seropositive individuals were 45.2% for infants <2 months old; 11.1% for infants 2-3 months old; 4.7% for infants 4-5 months old; 28.6-40.0% for infants 6-12 months old; 25.0-70.3% for individuals 1-20 years old. CONCLUSIONS: Infection with these viruses is common in childhood though the prevalence of these viruses may vary from year to year.     

Seroepidemiology of human group C rotavirus in South Africa

Sera from three separate healthy population cohorts were used to determine the incidence of group C rotavirus infections in 1,356 South Africans. Using an enzyme-linked immunosorbent assay based on a recombinant group C rotavirus VP6 protein, the total percent positivity was found to be 34.4% (range, 33 to 38%), with almost half of the population infected after the age of 20 years.     

Seroepidemiology of HTLV-III (LAV) in the Federal Republic of Germany

Summary In 1984 10,281 sera were collected in the FRG and examined for antibodies to HTLV-III (LAV) with an enzyme-linked immunosorbent assay and confirmative tests. Of the German AIDS patients 81% have antibodies. Individuals belonging to AIDS risk groups, homosexuals, haemophiliacs and i.v. drug abusers, have antibody frequencies between 25%–72%. The detection of HTLV-III antibodies in blood donours indicates that the virus is being transmitted by blood transfusions.Abbreviations AIDS acquired immunodeficiency syndrome - LAS lymphadenopathy syndrome - ARC AIDS related complex - LAV lymphadenopathy associated virus - HTLV-III human T-lymphotropic virus type III - HBV hepatitis B virus     

Seroepidemiology of human group C rotavirus in the UK

The gene coding for the major inner capsid protein VP6 of human group C rotavirus was cloned into baculovirus using the pBlueBac2^TM vector and expressed in insect cells. When cultured in High Five^TM cells, VP6 was expressed at a high level and exported to the cell culture medium. Purified VP6 was used to immunise rabbits. Hyperimmune rabbit serum, which reacted with native human group C rotavirus in infected cells, was used to develop and optimise an EIA for the detection of antibodies to group C rotavirus using the recombinant VP6 as a source of antigen. In a local epidemiological survey of 1000 sera grouped by age, an average of 43% of samples were found to have antibodies to human group C rotavirus with the highest proportion (66%) in the 71–75 year age group. In comparison, 97% of adults and 85% of children had antibodies to recombinant VP6 from the bovine RF strain of group A rotavirus. These results suggest that infection with human group C rotavirus is a common occurrence despite the apparent rarity of reports of human group C rotavirus in clinical samples from patients with gastroenteritis. J. Med. Virol. 52:86–91, 1997. © 1997 Wiley-Liss, Inc.