Gel electrophoretic analysis of nuclear matrix fractions isolated from different human cell lines

The nuclear matrix is operationally defined as the structure that remains after nuclei are extracted with nonionic detergent and with high salt and are digested with nucleases. Thus the nuclear matrix protein composition is critically dependent on the isolation conditions. We have compared nuclear matrices isolated from human cell lines by two different methods. First, isolated nuclei were extracted as above to obtain a matrix fraction. This method showed a substantial contamination by cytoplasmic intermediate filaments but immunization of mice resulted in antibodies recognizing nuclei and the mitotic spindle apparatus. Second, a nuclear matrix fraction was made by extracting whole cells as above and dissolving the residue in urea and dialysing against an assembly buffer to precipitate intermediate filament proteins (Fey, E. G. and Penman, S., Proc. Natl. Acad. Sci. USA 1988, 85, 121-125). Such fractions showed complex protein patterns in silver-stained two-dimensional gels for four cell lines: HeLa, MCF-7, SW13 and the U333CG/343MG glioma line. While some proteins in the nuclear matrix fraction were common to all cell lines, others appeared cell-line specific. Two-dimensional gels and the immunoresponse in mice again showed contamination of these preparations with cytoplasmic proteins. These results clearly show the difficulties associated with protein chemical analysis of nuclear matrices: the preparations have substantial cytoplasmic contamination, the polypeptide composition is extremely complex and the yield of individual polypeptides is low. Thus, without further experiments one cannot say which proteins are true nuclear matrix components.(ABSTRACT TRUNCATED AT 250 WORDS)

p53 protein and vimentin in invasive ductal NOS breast carcinoma--relationship with survival and sites of metastases

p53 protein and vimentin status were available from immunocytochemical studies of 253 formalin-fixed paraffin-embedded invasive ductal not otherwise specified (NOS) carcinomas from patients for whom follow-up data was also on file. For the 127 node-negative patients, multivariate analysis showed a highly significant correlation between p53 and vimentin (P < 0.001), a strong correlation between vimentin and probability of survival to 90 months but only a weak association between p53 and survival to 90 months. p53 also never entered trees of prognostic indicators derived using stepwise regression with Kaplan-Meier statistics for node-negative and node-positive subgroups, while vimentin status dominated the node-negative trunk. In addition, p53 and vimentin status were analysed versus the site of the first distant metastasis for node-negative and node-positive patients. Analysis by p53 status showed no significant effect on visceral metastases. In contrast, vimentin-positive primaries metastasised twice (and in node-negative patients, 3.5 times) as often to lung, liver and brain as did the vimentin-negative primaries. Both p53-positive and vimentin-positive tumours showed a significantly lower tendency to metastasise to the bone than did their negative counterparts.

Immunohistochemical profile of invasive lobular carcinoma of the breast: predominantly vimentin and p53 protein negative, cathepsin D and oestrogen receptor positive

Vimentin, p53 protein and cathepsin D positivity were assessed by immunohistochemistry, and oestrogen receptor (ER) by an enzyme immunoassay, in invasive lobular carcinomas (LC) of the breast. While vimentin was positive in only 5% (3/57) and p53 protein was positive only in 3% (2/63), cathepsin D was expressed in 86% (48/56) and ER in 78% (25/32). Classical LC were negative for p53 protein and all except one were cathepsin D positive. These results are in contrast to invasive ductal breast carcinomas (DC), where the reported average incidence of vimentin and p53 protein is much higher (19% and 33% respectively) and that of cathepsin D and ER lower (63% and 67% respectively). Thus lack of expression of vimentin and lack of p53 positivity together with high incidence of expression of cathepsin D and ER are more often associated with lobular than with ductal differentiation of invasive breast cancer. The results show that LC, distinguished morphologically, can further be defined by its immunohistochemical profile. This in turn may point to underlying biological differences between LC and DC.

Increased PCNA/cyclin index correlates with severity of duodenitis defined by histological criteria

The proliferative activity of crypt epithelial cells was studied in 64 duodenal biopsies using immunohistochemistry and proliferating cell nuclear antigen (PCNA)/cyclin monoclonal antibodies in alcohol-fixed paraffin-embedded sections. A positive correlation between duodenitis as defined by histological criteria and increased mean percentage of PCNA positive crypt cell nuclei (PCNA index) was found. The mean PCNA index in normal mucosa was 11.8 +/- 2.7% (mean +/- SD), in mild (grade 1) duodenitis 17.3 +/- 3.9%, in moderate (grade 2) 30.6 +/- 6.9%, and in severe (grade 3) duodenitis 41.1 +/- 8.5%. The inclusion of PCNA index, which is easily measured in paraffin-embedded sections, in the existing histopathological grading systems of duodenitis may improve their clinical relevance.

In Situ Observations of Aerosol and Chlorine Monoxide After the 1991 Eruption of Mount Pinatubo: Effect of Reactions on Sulfate Aerosol

Highly resolved aerosol size distributions measured from high-altitude aircraft can be used to describe the effect of the 1991 eruption of Mount Pinatubo on the stratospheric aerosol. In some air masses, aerosol mass mixing ratios increased by factors exceeding 100 and aerosol surface area concentrations increased by factors of 30 or more. Increases in aerosol surface area concentration were accompanied by increases in chlorine monoxide at mid-latitudes when confounding factors were controlled. This observation supports the assertion that reactions occurring on the aerosol can increase the fraction of stratospheric chlorine that occurs in ozone-destroying forms.

Psychiatric morbidity and compulsory admission among UK-born Europeans, Afro-Caribbeans and Asians in central Manchester

Psychiatric admissions in Central Manchester of Europeans, Afro-Caribbeans, and Asians (within three age-bands) were studied over four years. Among the Afro-Caribbean group there were more single or unemployed persons than in either the Asian or European groups, which suggested greater socio-economic disadvantage. Rates for first admissions and readmissions among Afro-Caribbeans were greater; among Asians they were similar except for the 16-29-year age-group, who tended to have lower rates than Europeans. A higher proportion of Afro-Caribbeans and Asians were psychotic. In the Afro-Caribbean group, the raised rates of admission were largely attributable to increased rates of schizophrenia. The highest rate occurred in second-generation (UK-born) Afro-Caribbeans and was nine times that among Europeans. The police were more frequently involved in the admissions of Afro-Caribbeans compared with Europeans or Asians. Higher proportions of Afro-Caribbeans and Asians who were readmitted were detained under the Mental Health Act 1983, when compared with Europeans.

Nuclear p53 protein accumulates preferentially in medullary and high-grade ductal but rarely in lobular breast carcinomas

Striking differences were found between different histological types of breast cancer when 263 invasive breast carcinomas were tested for nuclear p53 accumulation in formaldehyde-fixed paraffin sections. Nuclear p53 accumulation was found in > 10% of tumor cells in 61% of medullary carcinomas (22/36), 37% of grade 3 ductal not otherwise specified carcinomas (32/86), 4% of lobular carcinomas (2/47), and 0% (0/7) of mucinous carcinomas. Strong cytoplasmic p53 staining was noted in 32% of lobular carcinomas. High percentages of medullary and high-grade ductal breast carcinomas accumulate nuclear p53, but these tumors have favorable and poor prognoses, respectively. Thus, whereas nuclear p53 accumulation can be associated in these tumors with high morphological malignancy grades in general and with tumor cell proliferation in particular, p53 accumulation is not necessarily correlated with biological aggressiveness. Overall incidence of p53-positive tumors in a particular series of breast carcinomas (in our study 28%) will depend on the ratio of ductal not otherwise specified, medullary, and lobular carcinomas.

Microinjection of a monoclonal antibody against SPN antigen, now identified by peptide sequences as the NuMA protein, induces micronuclei in PtK2 cells

Several high molecular mass proteins which relocate from the interphase nucleus to the spindle poles during mitosis have been defined by antibodies. Microinjection experiments have shown that at least the antigen defined by SPN antibody plays a functional role during mitosis. Recently the cDNA sequence for human NuMA antigen was established and epitopes for antibodies to centrophilin, and to 1F1 and 1H1 antigens were found to be included in the NuMA protein. Here we show that immunoprecipitated SPN antigen reacts with an autoimmune human NuMA serum. In addition three peptides derived from immunoprecipitated human SPN by cyanogen bromide cleavage and covering more than fifty amino acids show a perfect fit with the sequence predicted for NuMA protein. Thus SPN antigen and NuMA are the same protein. Injection of SPN-3 antibody into interphase or mitotic PtK2 cells results in cells with micronuclei. For cells injected in prophase, prometaphase or metaphase 90%, 78% and 77% display defective cytokinesis or yield daughter cells with micronuclei. In contrast only 16% of cells injected in anaphase are abnormal. Thus SPN/NuMA antigen may be required during early, but not during later, stages of mitosis. Surprising parallels are seen between the effects of microinjecting SPN-3 antibody and treatment with colcemid and taxol of PtK2 and HeLa cells. Our results identify an important role during mitosis for the SPN/NuMA antigen.

The tight association of the tyrosine kinase substrate annexin II with the submembranous cytoskeleton depends on intact p11- and Ca(2+)-binding sites

Annexin II, a member of the annexin family of Ca(2+)- and lipid-binding proteins, is a major substrate of the pp60src kinase. It is unique within the annexin protein family, since it can form a tight heterotetrameric complex with the cellular protein ligand p11, a member of the S100 protein family. Within the cell, the annexin II2p11(2) complex is localized at the cytoplasmic surface of the plasma membrane in the submembranous cytoskeleton. This intracellular localization is thought to be the consequence of a typical annexin II property observed in vitro, its Ca(2+)-dependent binding to phospholipids and cytoskeletal elements (F-actin, non-erythroid spectrin). We employed site-directed mutagenesis to create mutant annexin II molecules with defects either in the p11-binding site or in the Ca(2+)-binding sites present in repeats 2, 3 and 4. The mutated annexin II derivatives were expressed in HeLa and RMCD cells by transfection of the appropriate DNA constructs in order to analyze the importance of p11- and Ca(2+)-binding for the intracellular localization of annexin II. Immunofluorescence microscopy with a monoclonal antibody that specifically detected the transfected annexin II derivatives indicated that the Ca(2+)-dependent incorporation of annexin II into the submembranous network depended on its ability to form the annexin II/p11 complex and on the presence of intact Ca(2+)-binding sites. Neither monomeric annexin II lacking an intact p11-binding site, nor the annexin II mutant with defects in the Ca(2+)-binding sites in repeats 2, 3 and 4 were associated with the Triton X-100-resistant network of the submembranous cytoskeleton.

Cathepsin D in invasive ductal NOS breast carcinoma as defined by immunohistochemistry. No correlation with survival at 5 years

Cathepsin D expression was assessed by immunohistochemistry in 59 node-negative and 77 node-positive infiltrative ductal not otherwise specified (NOS) breast carcinomas and compared with overall survival at 90 months. Cancer cells in 60% (81/136) of the tumors expressed cathepsin D. In the stroma of 33% (18 of 55) cathepsin D negative tumors, numerous strongly cathepsin D positive, benign macrophage-like cells were found. Multivariate analysis showed no significant correlation of cathepsin D expression and overall survival for all patients for node-negative and node-positive patients and for patients with vimentin-positive and -negative tumors. However, in node-negative but not in node-positive patients, a trend for better survival for patients with cathepsin-positive vimentin-negative tumors and worse survival for those with cathepsin-positive vimentin-positive tumors was noted. Due to the low number of patients in these subgroups, neither trend reached significance. Cathepsin D expression was independent of patient age, size, and histologic grade of tumor, and vimentin expression. However, in the node-positive group, negative correlation of cathepsin D and vimentin expression was found. We suggest that prognostic significance of cathepsin D in infiltrative ductal NOS breast carcinomas may be associated with the pathway of its synthesis rather than with its mere presence in tumor cells.

Ability to organize microtubules in taxol-treated mitotic PtK2 cells goes with the SPN antigen and not with the centrosome

The SPN antigen plays an essential role in mitosis, since microinjection of antibodies causes mitotic arrest. Here we show, by examination of the relative locations of SPN antigen, the centrosomal 5051 antigen and tubulin in normal mitotic, and in taxol-treated mitotic cells, that the SPN antigen is involved in organizing the microtubules of the spindle. The 210 kDa protein defined as SPN antigen relocates from the nuclear matrix to the centrosome at prophase, remains associated with the poles at metaphase and anaphase, and dissociates from the centrosomes in telophase. In taxol-treated mitotic cells, SPN staining shows a striking redistribution while 5051 antigen remains associated with centrosomes. SPN antigen is seen at the plasma membrane end of the rearranged microtubules. SPN antigen is always at the center of the multiple microtubule asters (5 to 20 per cell) induced by taxol, whereas 5051 again remains associated with the centrosomal complex (1 to 2 foci per cell). Microtubule nucleation is associated with the SPN antigen rather than with the 5051 antigen. Microinjection of SPN-3 antibody into taxol-treated mitotic PtK2 cells causes disruption of the asters as judged by tubulin staining of the same cells. Finally, SPN antigen extracted in soluble form from synchronized mitotic HeLa cells binds to, and sediments with, pig brain microtubules stabilized by taxol. This association of SPN antigen with microtubules is partially dissociated by 0.5 M NaCl but not by 5 mM ATP. Thus SPN antigen binds to microtubules in vitro and seems to act as a microtubular minus-end organizer in mitotic cells in vivo.

A shared epitope in the acetylcholine receptor-alpha subunit and fast troponin I of skeletal muscle. Is it important for myasthenia gravis?

The monoclonal antibody MAb 155, isolated by Tzartos et al, recognizes the alpha subunit of acetylcholine receptor (AChR) and stains type II skeletal muscle fibers but does not decorate heart muscle. In addition it reacts with most myasthenia gravis-associated thymomas. The authors show by immunoblotting techniques that the myofibrillar antigen is a 23 kd protein and by partial protein sequence data identify it as fast troponin I. Fast troponin I from various species contains the sequence EEKSGMEGRK close to the C-terminal end at positions 165 to 174. The first lysine (K) is crucial for MAb 155 reactivity since its substitution by methionine and leucine in slow troponin I and cardiac troponin I, respectively, abolishes MAb 155 reactivity. The epitope identified on troponin I is homologous in sequence with the MAb 155 epitope on the AChR alpha subunit established by direct peptide binding as KSAIEGIK (positions 373-380). The authors consider whether fortuitously shared epitopes can be responsible for the high level of autoantibodies to AChR and to muscle proteins seen in many MG patients.

Neurofilament epitopes in thymoma and antiaxonal autoantibodies in myasthenia gravis

Expression by neoplastic thymic epithelial cells of acetylcholine-receptor (AChR) epitopes is associated with the presence of AChR autoantibodies and the development of myasthenia gravis. We studied thymic tumours from patients with and without myasthenia gravis for the expression of neurofilament epitopes by immunohistochemistry with four monoclonal antibodies. There was very little antibody binding in control samples (healthy thymus, or thymitis) or in medullary and mixed thymomas, but neurofilament epitopes were strongly expressed in all cortical thymomas and thymic carcinomas. In addition, the frequency of serum autoantibodies against axons was significantly higher among myasthenic patients with thymic epithelial tumours than among age-matched controls (7/10 vs 3/50; p less than 0.01).

Keratin-positive reticulum cells in fine needle aspirates and touch imprints of hyperplastic lymph nodes. A possible pitfall in the immunocytochemical diagnosis of metastatic carcinoma

Fine needle aspirates and touch imprints of 36 hyperplastic (reactive) lymph nodes were tested for the presence of keratin and desmin. Keratin-positive cells with morphologic characteristics corresponding to extrafollicular (fibroblastic) reticulum cells were found in 18% of the fine needle aspirates and 42% of the touch imprints. The number of keratin-positive reticulum cells varied from 1 to greater than 30 per slide. Desmin-positive cells with similar morphology were found in 23% of fine needle aspirates and 37% of touch imprints, and the number of such cells per slide ranged from 2 to greater than 70. The relatively frequent occurrence of keratin-positive reticulum cells in these preparations from hyperplastic lymph nodes should be taken into account if keratin antibodies are used to search for carcinoma micrometastases.

Microinjection of IFA antibody induces intermediate filament aggregates in epithelial cell lines but perinuclear coils in fibroblast-like lines

The murine monoclonal IFA antibody recognizes a conserved sequence present in almost all intermediate filament (IF) proteins. When IFA antibody was injected into 13 different primary or established cell lines, striking differences were detected between epithelial and fibroblastic cell lines. In epithelial cells keratin IFs were broken down within 4 h into numerous spheroid aggregates scattered throughout the cytoplasm. Keratin aggregates were first detected in the cytoplasmic periphery. In contrast, in fibroblastic cells, injection of IFA antibody led to the formation of perinuclear coils of vimentin. IFA antibody at a concentration of greater than 1 mg/ml had to be injected to initiate these transitions. When HeLa cells, which contain separate networks of vimentin and keratin filaments, were injected with IFA antibody, vimentin did not form perinuclear coils but was instead found together with keratin in aggregates. Electron micrographs of HeLa cells injected with IFA antibody showed that the aggregates have diameters between 0.5 and 2.6 microns and resembled the keratin aggregates observed in certain mitotic epithelial cells. Although the ultrastructural studies support an association of some aggregates with desmosomes, aggregates were, however, also induced by injection of IFA antibody into human keratinocytes in low calcium medium under conditions where desmosomes were not present.

A striational muscle antigen and myasthenia gravis-associated thymomas share an acetylcholine-receptor epitope

The coincidence of autoantibodies against the acetylcholine receptor (AChR) and muscle striational antigens (SA) is a characteristic finding in thymoma-associated myasthenia gravis (MG), but their origins are still unresolved. Some common muscle antigens that were shown to be targets of anti-SA autoantibodies in thymoma-associated MG have also been detected in normal or neoplastic thymic epithelial cells, suggesting that the release of (eventually altered) antigens from the thymic tumors could elicit SA autoimmunity. In contrast to this model, we report here that titin, which is a recently reported target of SA autoimmunity, is not expressed in thymomas. In addition, we show that skeletal muscle type-II fibers exhibit a striational immunoreactivity with monoclonal antibody mAb155, which was previously identified to label a very immunogenic cytoplasmic epitope of the AChR and neoplastic epithelial cells of MG-associated thymomas. We conclude from these findings that titin autoimmunity in thymoma-associated MG is either due to a molecular mimicry mechanism involving tumor antigens (other than titin) or is a secondary phenomenon following release of titin from muscle. Based on the common immunoreactivity of the AChR, a striational antigen and thymoma, we suggest as the pathogenetic mechanism of thymoma-associated MGa "circulus vitiosus" in which SA autoimmunity could help maintain the AChR autoimmunity that is primarily elicited by the thymomas.

A 210 kDa nuclear matrix protein is a functional part of the mitotic spindle; a microinjection study using SPN monoclonal antibodies

Six monoclonal antibodies identify a 210 kDa polypeptide which shows a cell cycle specific redistribution from the nucleus to the mitotic spindle. In interphase cells this polypeptide was localized in the nucleus and behaved during differential cell extraction as a component of the nuclear matrix. It accumulated in the centrosome region at prophase, in the pole regions of the mitotic spindle at metaphase and in crescents at the poles in anaphase, and reassociated with the nuclei as they reformed in telophase. Due to its staining pattern we call the protein the Spindle Pole-Nucleus (SPN) antigen. The localization of SPN antigen during mitosis was dependent on the integrity of the spindle since treatment of cells with nocodazole resulted in the dispersal of SPN antigen into many small foci which acted as microtubule organizing centres when the drug was removed. The SPN antigen was present in nuclei and mitotic spindles of all human and mammalian cell lines and tissues so far tested. When microinjected into the cytoplasm or nuclei of HeLa cells, one antibody caused a block in mitosis. Total cell number remained constant or decreased slightly after 24 h. At this time, about half the cells were arrested in a prometaphase-like state and revealed aberrant spindles. Many other cells were multinucleate. These results show that the SPN antigen is a protein associated with mitotic spindle microtubules which has to function correctly for the cell to complete mitosis.

Unexpected immunoreactivities of intermediate filament antibodies in human brain and brain tumors

Immunoreactivities of 35 different monoclonal antibodies (MAbs) that detect intermediate filaments were studied systematically on serial cryostat sections of 14 well-defined human gliomas (five astrocytomas, three oligodendrogliomas, six glioblastomas) and on normal brain. Glial fibrillary acidic protein (GFAP), vimentin, desmin, neurofilaments, and broad-specificity keratin MAbs, as well as MAbs that recognize several or only single keratin polypeptides, were used. Unexpected reactivities were surprisingly frequent. As these may lead to diagnostic confusion and misinterpretation on this material, the authors investigated these phenomena more thoroughly. Four major sources of artifactual staining were found: 1) positive staining attributable to the rabbit gamma G immunoglobulins used in the alkaline phosphatase anti-alkaline phosphatase technique; 2) certain desmin and keratin MAbs cross-reacted with astrocytic glia and with other brain-specific epitopes; 3) technical difficulties; 4) some MAbs directed against neurofilaments and keratins showed unexpected reactivities only on individual anaplastic gliomas. The implications of these findings for intermediate filament typing of neuropathologic material are discussed.

Cytokeratin expression and vimentin content in large cell anaplastic lymphomas and other non-Hodgkin's lymphomas

The immunophenotypes of 74 malignant lymphomas (9 Hodgkin's disease, 19 low-grade B-cell, 20 high-grade B-cell, 8 T-cell, and 18 large cell anaplastic lymphomas [LCAL]) have been characterized with antibodies against leucocyte differentiation antigens, keratin, and vimentin. All the non-LCAL were CD45 positive and keratin negative. The LCALs had a more varied immunophenotype, with CD45 present only in 11 of 18 cases and keratin present in 5 of 18 of these rare lymphomas. The lymphoid origin of these latter cases was proven by gene rearrangement studies. All LCALs were CD30+, and, where tested, vimentin positive. Of four different vimentin monoclonal antibodies tested, V9 and MVI stained the highest number of lymphomas. Positive staining of tumor cells was seen in 61 of 71 cases. Vimentin-negative cases included Burkitt's as well as some follicular lymphomas.

Dendritic accessory cells derived from rat bone marrow precursors under chemically defined conditions in vitro belong to the myeloid lineage

Serum-free conditions have been developed to differentiate dendritic cells from a non-adherent fraction of rat bone marrow precursors by action of the multipotential and macrophage colony-stimulating factors further supplemented with linoleic acid, vitamin E, and vitamin D3. Accessory activity was demonstrated by the high potency of the dendritic cells to stimulate autologous T cell proliferation, whereas such cells were negative for Fc receptor-dependent phagocytosis, a characteristic macrophage feature. While the dendritic cells were weakly positive for alpha-naphtylbutyrate esterase, they strongly expressed RT.1 class II antigens. Apparently, these cells represent a more differentiated phenotype since they expressed the nuclear A/C lamins. By addition of serum to the cultures, the dendritic cells developed into macrophages, which were also lamin A/C-positive as well as strongly positive for alpha-naphtylbutyrate esterase. Thus, these dendritic cells belong to the myeloid lineage, and it appears as if serum factor(s) control differentiation at a mature level. Suitable conditions could also be established for large-scale cultures of dendritic cells, which would be useful for applications requiring higher numbers of cells.

Randomised controlled trial of day and in-patient psychiatric treatment. 2: Comparison of two hospitals

Acutely ill patients presenting for admission in two district psychiatric services were randomly allocated to day-hospital or in-patient care. In both services a quarter of all admissions could not be allocated because they were too ill (half of these were compulsory admissions); these patients were predominantly manic and schizophrenic patients with pronounced psychotic symptoms and disturbed behaviour. In one service 80% (41/51) of patients randomly allocated to day-hospital treatment were successfully engaged in treatment compared with 54% (19/35) in the other service. This difference arose because only patients with mildly disturbed behaviour could be treated at the second day hospital. For patients who were successfully allocated, the outcome of treatment was similar in terms of psychiatric symptoms and social functioning. The results of a treatment trial for acutely ill patients in one district service cannot be generalised to other district services without due attention to the factors, such as staffing levels, which determine the degree of disturbed behaviour that can be tolerated in the day hospital.

Vimentin expression appears to be associated with poor prognosis in node-negative ductal NOS breast carcinomas

Vimentin expression in tumors from 83 node-negative and 112 node-positive patients with infiltrative ductal not otherwise specified (NOS) breast carcinomas has been compared with 5-year survival. For node-negative, but not for node-positive patients, there was a significant inverse relation between vimentin expression and survival. Five-year survival of node-negative patients with vimentin-positive tumors was significantly worse compared with vimentin-negative tumors (P less than 0.0001). In the node-negative group, only 36% of patients with vimentin-positive tumors but 82% of patients with vimentin-negative tumors survived 5 years. Tumors of all eight node-negative patients with ductal NOS cancer who died in the first 27 months expressed vimentin. Multivariate analysis of the node-negative group showed a strong correlation of vimentin expression and overall survival, but weak and not significant correlation between histologic grade or size and overall survival at 5 years. Thus vimentin expression seems to be a strong indicator of poor prognosis in node-negative ductal NOS breast carcinomas.

Vimentin is preferentially expressed in high-grade ductal and medullary, but not in lobular breast carcinomas

Two hundred sixty-two invasive breast carcinomas dating from 1979 to 1984 were tested for vimentin and keratin on formaldehyde-fixed paraffin-embedded sections. None of 26 lobular carcinomas expressed vimentin. Vimentin expression in 10% or more of tumor cells was found in 78% of medullary (14 of 18), in 16% of ductal not otherwise specified (NOS) (35 of 214), and in two of four mucinous carcinomas. A further seven tumors showed vimentin expression in less than 1% to 10% of the cells. Vimentin was expressed in tumor cells of 30% (28 of 93) of grade III invasive ductal NOS carcinomas versus 7% (7 of 105) of grade II and 0% of grade I carcinomas (0 of 10). Vimentin was found to be preferentially expressed in tumors growing in broad, often anastomosing bands or sheets with extensive necrosis, scanty supportive stroma, high nuclear grade, and numerous mitoses. The authors conclude that vimentin is not detected in lobular carcinomas, but is preferentially expressed in medullary and in high-grade ductal NOS breast carcinomas.

Induction of nuclear lamins A/C in macrophages in in vitro cultures of rat bone marrow precursor cells and human blood monocytes, and in macrophages elicited in vivo by thioglycollate stimulation

Hemopoietic cells from blood and bone marrow of mammals usually do not express lamins A/C but only lamin B, and this feature distinguishes these cells from the vast majority of somatic cells of the adult animal, which reveal lamins A/C as well as lamin B. Here we have cultivated rat bone marrow precursor cells and human monocytes isolated from peripheral blood in tissue culture supplemented with certain growth factors. These conditions allow bone marrow precursor cells and monocytes to differentiate almost quantitatively into accessory cells and/or mature macrophages. The different cell types in the cultures can be identified both morphologically and by other assays. Antibodies specific for mouse A/C lamins, human A/C lamins, or B lamins have been used to define the lamin complement as a function of time in culture and of cell type. A dramatic increase in lamin A/C-positive cells was observed in the first 3 days of culture with both accessory cells and macrophages expressing lamins A/C as soon as such cell types could be identified. Parallel in vivo experiments showed that treatment with thioglycollate caused the percentage of lamin A/C-positive peritoneal macrophages to increase from 5 to 80% between Days 0 and 6.

On the nature of serological tissue polypeptide antigen (TPA); monoclonal keratin 8, 18, and 19 antibodies react differently with TPA prepared from human cultured carcinoma cells and TPA in human serum

A panel of monoclonal antibodies which recognize the rod domains of human keratin 8, 18, or 19 was tested for its capacity to replace TPA antiserum as anchoring antibody in a two-site TPA immuno-radiometric assay kit. All six antibodies could anchor a TPA preparation, with varying efficiencies, when iodinated TPA antiserum monitored antigen binding. Conversely, the soluble keratin 8, 18, and 19 rod complex could efficiently replace the TPA preparation as antigen when TPA antiserum anchored and detected antigen binding. Moreover, in immunoblots the TPA antiserum recognized the rod domains of human keratins 8, 18, and 19. In contrast to the general reaction of the keratin antibodies with a TPA preparation, the reactions with TPA in human serum were antibody and sample dependent. A keratin 19- and a keratin 8-specific antibody anchored TPA in all sera consistently and efficiently, while the other 4 antibodies anchored serological TPA inefficiently. TPA in human serum was found in immunoblots to be somewhat more heterogeneous in size than the standard TPA preparation. The data presented here indicate that TPA in patients' sera is a degradation product of keratins 8, 18, and 19. The significance of these findings is discussed.