Lewis x Antigen is Associated to Head and Neck Squamous Cell Carcinoma Survival.

Head and neck squamous cell carcinoma (HNSCC) is an aggressive disease with poor prognosis without appropriate prognostic markers. Previous research shows that Lewis antigens have been involved in carcinoma dissemination and patients´ survival. Fucosyl and sialyltransferases are the enzymes implicated in the Lewis antigens synthesis. The purpose of this study was to evaluate the prognostic utility of Lewis antigens in HNSCC. We conducted a prospective research including histological samples from 79 patients with primary HNSCC. Lewis x and sialyl Lewis x expression were detected by immunohistochemistry; patient's data, progression free, and overall survival were documented. A statistical correlation study of antigenic expression and patients´ histopathological variables was performed. Cox regression models with internal validation procedures were employed to analyze survival data. By immunohistochemistry, Lewis x was detected in 34/79 (43%) tumor samples, while sialyl Lewis x only in 11/79 (14%). Lewis x expression showed a positive correlation with tumor differentiation and a better overall survival for Lewis x + patients was detected. Moreover, multivariate Cox's regression analysis showed that Lewis x is an independent predictor of better overall survival. The in silico analysis supported the presence of deregulated fucosyl (FUT4) and sialyltransferase (ST3GAL4) in the Lewis synthetic pathway related to patient survival. These results suggest that Lewis x expression is associated with a better outcome in patients with HNSCC.

From Molecular Biology to Clinical Trials: Toward Personalized Colorectal Cancer Therapy.

During the past years, molecular studies through high-throughput technologies have led to the confirmation of critical alterations in colorectal cancer (CRC) and the discovery of some new ones, including mutations, DNA methylations, and structural chromosomal changes. These genomic alterations might act in concert to dysregulate specific signaling pathways that normally exert their functions on critical cell phenotypes, including the regulation of cellular metabolism, proliferation, differentiation, and survival. Targeted therapy against key components of altered signaling pathways has allowed an improvement in CRC treatment. However, a significant percentage of patients with CRC and metastatic CRC will not benefit from these targeted therapies and will be restricted to systemic chemotherapy. Mechanisms of resistance have been associated with specific gene alterations. To fully understand the nature and significance of the genetic and epigenetic defects in CRC that might favor a tumor evading a given therapy, much work remains. Therefore, a dynamic link between basic molecular research and preclinical studies, which ultimately constitute the prelude to standardized therapies, is very important to provide better and more effective treatments against CRC. We present an updated revision of the main molecular features of CRC and their associated therapies currently under study in clinical trials. Moreover, we performed an unsupervised classification of CRC clinical trials with the aim of obtaining an overview of the future perspectives of preclinical studies.

Humoral immune response against tumoral mucin 1 (MUC1) in breast cancer patients.

The aim of this study was to elucidate whether the IgG humoral immune response to breast cancer cells is directed to the aberrant mucin-1 (MUC1) associated to this type of cancer. To this aim, an adaptation of immunohistochemistry (IHC) was performed on samples of 45 breast cancer tissues, 12 benign disease tissues, and 31 normal tissues, incubated with matched serum samples from the same patients. Each serum sample was also incubated, with a modified immunocytochemistry (ICC), with MCF7 cells. In both techniques, serum was employed instead of the primary antibody. In the case of IHC, the reactivity with sera diminished when added after previous incubation of the tumor/tissue with an anti-MUC1 mAb; the reduction in reactivity was: from 93% to 44% in breast cancer tissues, and from 100% to 67% in benign disease tissues. The reactivity of normal samples (36%) remained unchanged. In the case of ICC, the reactivity with sera decreased after incubation with anti-MUC1 mAb from 71% to 16% in breast cancer tissues, from 83% to 0% in benign disease tissues, and from 52% to 10% in normal serum samples. These results were confirmed employing siRNA MUC1 transient gene knockdown. By Western blot analysis -after immunoprecipitation (IP) of the circulating MUC1- and ELISA, the TF antigen was detected in circulating MUC1 in all breast cancer and benign samples while Tn was detected in 38% of the samples.
The existence of IgG autoantibodies against aberrantly glycosylated MUC1 may have a protective role and may contribute to a better prognosis in some patients. Enhancement of this natural immune response may constitute an alternative therapeutic strategy.

Identification and expression of the epithelial Muc1 mucin in normal feline tissues.

Many pathogens require direct binding to, or penetration of, mucosal cells to cause pathology. Cell surface mucins are critical components of mucosal defense. Mucin 1, named MUC1 in humans and Muc1 in non-human species, is a transmembrane glycoprotein expressed in apical mammalian epithelial tissues. The aim of this study was to determine the Muc1 profile expression in healthy cat epithelial tissues. An extensive analysis of Muc1 expression was performed by immunohistochemistry (IHC), Western blot (WB) and RT-PCR. By IHC, the presence of Muc1 protein was observed in the epithelial cells of the esophagus, stomach, trachea, lung, small and large intestine, liver, pancreas, salivary glands, lactating mammary glands and bladder. The predominantly linear patterns of reaction as well as the ubiquitous expression of feline Muc1 were consistent with normal human tissues. By WB, a band of 35kDa, corresponding to that predicted for the Muc1 cytoplasmic tail, was detected. The RT-PCR analysis showed a fragment of 115bp, consistent with that found in MCF7 and T47D human cell lines. The results showed that the widest distribution of feline Muc1 expression is in the mucosal tissues most at risk of infections such as the gastrointestinal tract, respiratory tract and lactating mammary gland. This study provides a normal model of cat Muc1 pattern expression as a starting point to evaluate and compare the expression of this epithelial mucin in pathological feline tissues. We believe that the CT33 antibody and the universal primers designed could be valuable tools for veterinary pathologists involved in the diagnostic interpretation of alterations in Muc1 expression of infected tissues in cats.

Expression of conserved mucin domains by epithelial tissues in various mammalian species.

UNLABELLED: Mucins are related to infectious and non-infectious diseases in Veterinary and Human Medicine. MUC1 mucin is a transmembrane glycoprotein expressed on the apical surface of human epithelia while MUC5AC is the predominant secreted mucin expressed in human gastric epithelium and goblet cells of lung and eyes. MUC5AC C-terminus cysteine rich regions and the cytoplasmic tail of MUC1 domains are conserved among several mammalian species. OBJECTIVE: to compare the expression of MUC1 and MUC5AC mucins in mammalian epithelia. CT33 anti-MUC1 cytoplasmic tail (MUC1CT) polyclonal antibody and 45M1 anti-MUC5AC monoclonal antibody were employed. By immunohistochemistry, MUC1CT was expressed in most tissues while MUC5AC was restricted to gastric surface epithelium and goblet cells from trachea and lung. By western blot, MUC1CT showed a band at approximately 35 kDa in most tissues; MUC5AC revealed bands at >180 kDa in stomach and lung secretions from rat, cat, pig and cow. When rat MUC5AC was immunoprecipitated, a band at about 180 kDa was obtained.

Differential expression of MUC1 and carbohydrate antigens in primary and secondary head and neck squamous cell carcinoma.

BACKGROUND: In head and neck squamous cell carcinoma (HNSCC), tumor markers may be helpful to evaluate prognosis accurately as well as to improve therapy selection. Detection of human MUC1 has been widely employed for the evaluation of carcinoma patients. This article aims to study MUC1, Tn, sTn, and Lewis antigenic expression in primary HNSCC, lymph node metastasis, and local recurrences. METHODS: We used immunohistochemistry, tissue homogenization and differential centrifugation, isopycnic density gradient centrifugation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot. RESULTS: In primary tumors, MUC1 was detected in 80.0% of the samples; sLewis x in 23.2%, Lewis x in 45.6%, and Lewis y in 40.8%. Tn and sTn were found in 4.0% and 6.4% of samples, respectively. In metastatic lymph nodes, MUC1 showed a similar positive reaction as in primary tumors. Lewis y was detected in 20% lymph nodes whereas Lewis x, sLewis x, Tn, and sTn did not show differences. Some recurrences expressed MUC1 and only a few Lewis antigens, whereas Tn and sTn were not detected. CONCLUSION: In primary HNSCC and metastatic nodes, a high expression of MUC1 and Lewis antigens was detected that diminished in local recurrences. We also found that differentiated tumors mainly expressed a linear pattern of MUC1CT and Lewis x.

Lewis x is highly expressed in normal tissues: a comparative immunohistochemical study and literature revision.

An immunohistochemical analysis was employed to determine the expression of carbohydrate antigens associated to mucins in normal epithelia. Tissue samples were obtained as biopsies from normal breast (18), colon (35) and oral cavity mucosa (8). The following carbohydrate epitopes were studied: sialyl-Lewis x, Lewis x, Lewis y, Tn hapten, sialyl-Tn and Thomsen-Friedenreich antigen. Mucins were also studied employing antibodies against MUC1, MUC2, MUC4, MUC5AC, MUC6 and also normal colonic glycolipid. Statistical analysis was performed and Kendall correlations were obtained. Lewis x showed an apical pattern mainly at plasma membrane, although cytoplasmic staining was also found in most samples. TF, Tn and sTn haptens were detected in few specimens, while sLewis x was found in oral mucosa and breast tissue. Also, normal breast expressed MUC1 at a high percentage, whereas MUC4 was observed in a small number of samples. Colon specimens mainly expressed MUC2 and MUC1, while most oral mucosa samples expressed MUC4 and MUC1. A positive correlation between MUC1VNTR and TF epitope (r=0.396) was found in breast samples, while in colon specimens MUC2 and colonic glycolipid versus Lewis x were statistically significantly correlated (r=0.28 and r=0.29, respectively). As a conclusion, a defined carbohydrate epitope expression is not exclusive of normal tissue or a determined localization, and it is possible to assume that different glycoproteins and glycolipids may be carriers of carbohydrate antigens depending on the tissue localization considered.

GATA3 protein as a MUC1 transcriptional regulator in breast cancer cells.

INTRODUCTION: Recent studies have demonstrated that members of the GATA-binding protein (GATA) family (GATA4 and GATA5) might have pivotal roles in the transcriptional upregulation of mucin genes (MUC2, MUC3 and MUC4) in gastrointestinal epithelium. The zinc-finger GATA3 transcription factor has been reported to be involved in the growth control and differentiation of breast epithelial cells. In SAGE (serial analysis of gene expression) studies we observed an intriguing significant correlation between GATA3 and MUC1 mRNA expression in breast carcinomas. We therefore designed the present study to elucidate whether MUC1 expression is regulated by GATA3 in breast cancer cells. METHODS: Promoter sequence analysis of the MUC1 gene identified six GATA cis consensus elements in the 5' flanking region (GATA1, GATA3 and four GATA-like sequences). Chromatin immunoprecipitation and electrophoretic mobility-shift assays were employed to study the presence of a functional GATA3-binding site. GATA3 and MUC1 expression was analyzed in vitro with a GATA3 knockdown assay. Furthermore, expression of GATA3 and MUC1 genes was analyzed by real-time RT-PCR and immunohistochemistry on breast cancer-specific tissue microarrays. RESULTS: We confirmed the presence of a functional GATA3-binding site on the MUC1 promoter region in the MCF7 cell line. We determined that GATA3 knockdown assays led to a decrease in MUC1 protein expression in MCF7 and T47D cells. In addition, we detected a statistically significant correlation in expression between GATA3 and MUC1 genes at the mRNA and protein levels both in normal breast epithelium and in breast carcinomas (p = 0.01). GATA3 expression was also highly associated with estrogen receptor and progesterone receptor status (p = 0.0001) and tumor grade (p = 0.004) in breast carcinomas. CONCLUSION: Our study provides evidence indicating that GATA3 is probably a mediator for the transcriptional upregulation of MUC1 expression in some breast cancers.

MUC1 expression and anti-MUC1 serum immune response in head and neck squamous cell carcinoma (HNSCC): a multivariate analysis.

BACKGROUND: HNSCC progression to adjacent tissue and nodes may be mediated by altered glycoproteins and glycolipids such as MUC1 mucin. This report constitutes a detailed statistical study about MUC1 expression and anti-MUC1 immune responses in relation to different clinical and pathological parameters which may be useful to develop new anti HNSCC therapeutic strategies. PATIENTS AND METHODS: Fifty three pre treatment HNSCC patients were included: 26 (49.1%) bearing oral cavity tumors, 17 (32.1%) localized in the larynx and 10 (18.8%) in the pharynx. Three patients (5.7%) were at stage I, 5 (9.4%) stage II, 15 (28.3%) stage III and 30 (56.6%) at stage IV. MUC1 tumor expression was studied by immunohistochemistry employing two anti-MUC1 antibodies: CT33, anti cytoplasmic tail MUC1 polyclonal antibody (Ab) and C595 anti-peptidic core MUC1 monoclonal antibody. Serum levels of MUC1 and free anti-MUC1 antibodies were detected by ELISA and circulating immune complexes (CIC) by precipitation in polyethylene glycol (PEG) 3.5%; MUC1 isolation from circulating immune complexes was performed by protein A-sepharose CL-4B affinity chromatography followed by SDS-PAGE and Western blot. Statistical analysis consisted in Multivariate Principal Component Analysis (PCA); ANOVA test (Tukey's test) was employed to find differences among groups; nonparametrical correlations (Kendall's Tau) were applied when necessary. Statistical significance was set to p < 0.05 in all cases. RESULTS: MUC1 cytoplasmic tail was detected in 40/50 (80%) and MUC1 protein core in 9/50 (18%) samples while serum MUC1 levels were elevated in 8/53 (15%) patients. A significant statistical correlation was found between MUC1 serum levels and anti-MUC1 IgG free antibodies, while a negative correlation between MUC1 serum levels and anti-MUC1 IgM free antibodies was found. Circulating immune complexes were elevated in 16/53 (30%) samples and were also statistically associated with advanced tumor stage. MUC1 was identified as an antigenic component of IgG circulating immune complexes. Moreover, poorly differentiated tumors were inversely correlated with tumor and serum MUC1 detection and positively correlated with node involvement and tumor mass. CONCLUSION: Possibly, tumor cells produce MUC1 mucin which is liberated to the circulation and captured by IgG antibodies forming MUC1-IgG-CIC. Another interesting conclusion is that poorly differentiated tumors are inversely correlated with tumor and serum MUC1 detection.

Influence of sialic acid removal on MUC1 antigenic reactivity in head and neck carcinoma.

To investigate the influence of sialic acid removal on MUC1 peptidic and carbohydrate epitope reactivity in head and neck squamous cell carcinoma (HNSCC), tumor samples belonging to 24 HNSCC patients were studied by standard immunohistochemistry (IHC) with and without desialylation with 0.1 U/ml neuraminidase. From each tumor sample, subcellular fractions were obtained and analyzed by SDS-PAGE and Western blotting (WB). Three monoclonal antibodies (MAbs) were used: C595 MAb directed to MUC1 protein core, an anti-Tn hapten MAb, and an anti-sTn hapten MAb; a comparative analysis between desialylated and sialylated samples was performed. By IHC without neuraminidase treatment, 19 of 24 samples reacted with anti-MUC1 peptidic epitope, while Tn hapten was not detected and sTn was found in 1 of 24 cases. Desialylation increased either the number of reacting cells or the intensity of the reaction with C595 and anti-Tn MAbs, and some negative samples became positive. On the other hand, sTn expression decreased with desialylation. By WB, several bands from >200 to 25 kDa were found; desialylation increased high-molecular-weight bands, diminishing the detection of low-molecular-weight ones. The use of desialylation is a suitable treatment that contributes to the exposure of MUC1-associated epitopes, which may be related to the spreading of HNSCC.

Tissue and serum MUC1 mucin detection in breast cancer patients.

Tumor MUC1 expression as well as levels of MUC1, MUC1 circulating immune complexes (MUC1-CIC) and free antibodies against MUC1 (IgG and IgM-MUC1) were evaluated in 70 breast cancer patients with different stages of disease. Controls included: 135 serum samples from healthy women, normal mammary tissue samples (n = 7) and benign breast disease specimens (n = 6). In all assays, pre- and post-vaccination serum samples from breast cancer patients belonging to a vaccination protocol developed at the Memorial Sloan Kettering Cancer Center (New York, USA) were included as controls. Serum MUC1 was measured through Cancer Associated Serum Antigen test and CA15-3 test. Employing ELISA, MUC1-CIC-IgG/M were measured with either C595 or SM3 monoclonal antibodies (MAb) as catchers and also free antibodies against MUC1 (IgG and IgM) using 100mer peptide as catcher. Employing multivariate statistical analysis, results were correlated with age, tumor type, stage of disease and grade of differentiation. By quantitative immunohistochemistry using three anti-MUC1 core protein MAbs (C595, HMFG2 and SM3), tumor MUC1 was detected in 60/70 (86%) breast cancer specimens which reacted with at least one of these MAbs. High MUCI serum levels were detected in 14/67 (21%); IgG and IgM anti-MUC1 antibodies were found elevated in 32 and 14%, respectively, while IgG-MUC1-CIC-measured with C595 in 42% and IgM-MUC1-CIC in 54%; finally, SM3 was positive in 43 and 18%, respectively. Results of these studies demonstrate that in a group of breast cancer patients, MUC1 was detected both in tissue specimens as well as free in serum samples; furthermore, MUC1 can also circulate complexed with IgG and IgM antibodies; thus an accurate measurement should include free and complexed forms. On the other hand, immunohistochemical studies on breast cancer tissues may contribute to reveal different MUC1 glycoforms.

Patterns of MUC1 tissue expression defined by an anti-MUC1 cytoplasmic tail monoclonal antibody in breast cancer.

Our aim was to determine the pattern of expression of MUC1 mucin cytoplasmic tail (MUC1 CT) in breast carcinoma. A total of 98 invasive breast adenocarcinoma tumor samples were assayed by immunohistochemical (IHC) analysis. The pattern of reaction was classified as membrane, cytoplasmic, or mixed. Subcellular fractions were prepared after SDS-PAGE and Western blotting. The antibodies employed were anti-MUC1 CT (CT2 monoclonal antibody, MAb) and C595 MAb against the extracellular MUC1 core protein. With the CT2 MAb, IHC showed a high percentage of positive staining in 93% of specimens, with membrane staining the most common pattern observed. C595 MAb was reactive in 73% of specimens. Similar percentages of membrane and cytoplasmic staining were found, mainly in a mixed pattern. Western blotting showed different bands. With the CT2 MAb, the membrane fraction showed the most intense reaction; a strong band of reaction was detected at approximately <30 kD. With the C595 MAb, in most cases a double band at 200 kD was found. In breast epithelium, the pattern of MUC1 CT expression may constitute an indicator of MUC1 production because it does not depend on glycosylation. The pattern and extension of MUC1 CT positivity do not vary according to the histopathological subtype of the tumor.

Investigación de la mucina de tipo 1 (MUC1) circulante y tisular en el cáncer de mama / Investigation of the circulating and tissue type 1 mucin (MUC 1) in the breast cancer

Las mucinas (MUC) son glicoproteínas que se localizan y expresan en la mayoría de los epitelios y han sido recientemente relacionadas con el cáncer de mama. entre ellas, la MUC1 constituye una mólecula de elevado peso molecular que en la célula maligna puede presentar una glicosilación aberrante o incompleta que la convierte en inmunogénica. Los objetivos del presente trabajo de investigación han sido: 1- estudiar la expresión celular de MUC1 en el cáncer de mama y en neoplasias mamarias benignas; 2- estudiar los niveles de MUC1 sérica como marcador tumoral; 3- investigar la relación entre la expresión sérica y tisular y 4- detectar anticuerpos séricos anti MUC1 libres y acomplejados. Se incluyeron 70 pacientes con cáncer de mama de las que se obtuvieron 70 muestras de tejido tumoral y 65 sueros y los controles fueron 5 muestras de tejido normal, 8 displasias y 135 sueros de mujeres sanas. además, se emplearon sueros de pacientes con cáncer de mama pre y post vacunación con un péptido derivado de MUC1. Por otra parte, se utilizaron 3 monoclonales (MAbs) que reaccionan con el centro proteico de la molécula de MUC1: C595, SM3 y HMFG2. Los métodos empleados fueron: inmunocito e inmunohistoquímica con procesamiento de imágenes y análisis cuantitativo, preparación de membranas subcelulares; SDS-PAGE y Western blot, cultivo primario de tumores malignos, ensayos de tumorigenicidad, detección de MUC1 circulante, determinación de complejos inmunes anti-MUC1 y detección de anticuerpos libres anti-MUC1 mediante ELISA (enzimoinmunoensayo en fase líquida); los datos fueron analizados estadísticamente. Los resultados fueron los siguientes: la inmunohistoquímica reveló que las muestras de cáncer de mama fueron positivas en el 73 por ciento con un patrón de expresión fundamentalmente en la membrana plasmática, o bien mixto tanto en la membrana plasmática como en el citoplasma. En los cultivos primarios se observó expresión de MUC1 principalmente citoplásmica en todos los casos con los MAbs empleados. En los controles, el patrón de reactividad fue apical o en la luz de las glándulas siendo negativo el SM3 para las neoplasias benignas. mediante Western-blot fue posible observar que las fracciones subcelulares de neoplasias malignas fueron positivas dando una banda de reacción de >200kD con los tres MAbs ensayados... (TRUNCADO) (AU)

Investigación de la mucina de tipo 1 (MUC1) circulante y tisular en el cáncer de mama / Investigation of the circulating and tissue type 1 mucin (MUC 1) in the breast cancer

Las mucinas (MUC) son glicoproteínas que se localizan y expresan en la mayoría de los epitelios y han sido recientemente relacionadas con el cáncer de mama. entre ellas, la MUC1 constituye una mólecula de elevado peso molecular que en la célula maligna puede presentar una glicosilación aberrante o incompleta que la convierte en inmunogénica. Los objetivos del presente trabajo de investigación han sido: 1- estudiar la expresión celular de MUC1 en el cáncer de mama y en neoplasias mamarias benignas; 2- estudiar los niveles de MUC1 sérica como marcador tumoral; 3- investigar la relación entre la expresión sérica y tisular y 4- detectar anticuerpos séricos anti MUC1 libres y acomplejados. Se incluyeron 70 pacientes con cáncer de mama de las que se obtuvieron 70 muestras de tejido tumoral y 65 sueros y los controles fueron 5 muestras de tejido normal, 8 displasias y 135 sueros de mujeres sanas. además, se emplearon sueros de pacientes con cáncer de mama pre y post vacunación con un péptido derivado de MUC1. Por otra parte, se utilizaron 3 monoclonales (MAbs) que reaccionan con el centro proteico de la molécula de MUC1: C595, SM3 y HMFG2. Los métodos empleados fueron: inmunocito e inmunohistoquímica con procesamiento de imágenes y análisis cuantitativo, preparación de membranas subcelulares; SDS-PAGE y Western blot, cultivo primario de tumores malignos, ensayos de tumorigenicidad, detección de MUC1 circulante, determinación de complejos inmunes anti-MUC1 y detección de anticuerpos libres anti-MUC1 mediante ELISA (enzimoinmunoensayo en fase líquida); los datos fueron analizados estadísticamente. Los resultados fueron los siguientes: la inmunohistoquímica reveló que las muestras de cáncer de mama fueron positivas en el 73 por ciento con un patrón de expresión fundamentalmente en la membrana plasmática, o bien mixto tanto en la membrana plasmática como en el citoplasma. En los cultivos primarios se observó expresión de MUC1 principalmente citoplásmica en todos los casos con los MAbs empleados. En los controles, el patrón de reactividad fue apical o en la luz de las glándulas siendo negativo el SM3 para las neoplasias benignas. mediante Western-blot fue posible observar que las fracciones subcelulares de neoplasias malignas fueron positivas dando una banda de reacción de >200kD con los tres MAbs ensayados... (TRUNCADO)

Aislamiento y caracterización de complejos inmunes asociados a tumores malignos y a lepra / Isolation and characterization of immune complexes associated with malignant tumors and leprosy

Hemos estudiado los complejos inmunes circulantes (CIC) asociados a diversas enfermedades tales como neoplasias malignas, lepra y artritis reumatoidea. Se realizó la detección de CIC empleando diferentes técnicas: test de combinación a 125I-Clq, a IgG radioactiva, a conglutinina bovina marcada, test de aglutinación de plaquetas y precipitado en polietilen glicol 3,5% y 2,5%. Posteriormente, se desarrollaron técnicas de asislamiento y separación de los CIC para la obtención de sus fracciones constituyentes en ciertos tumores malignos y en lepra, basadas en la afinidad de los CIC por proteína A y en la acción de diferentes buffers. Estos métodos se aplicaron previamente a complejos inmunes preparados in vitro (BSA-aBSA, OVA-aOVA, etc.). El análisis de las fracciones se realizó por SDS-PAGE, inmunoelectroforesis, inmunoblotting, etc. Los resultados fueron los siguientes: se observó una elevada incidencia de niveles de CIC positivos coincidentes con los estadios de actividad clínica, disminuyendo en la remisión. Así mismo en algunos grupos de pacientes los hallazgos de CIC permitieron evaluar la eficacia terapéutica. Con el desarrollo de técnicas de separación de CIC se obtuvieron fracciones inmunológicamente activas provenientes de los CIC aislados del suero de pacientes portadores de tumores malignos, especialmente del tubo digestivo y de mama y posteriormente en el suero de individuos con lepra. Los resultados obtenidos hasta la fecha han demostrado la utilidad clínica de los estudios...

Aislamiento y caracterización de complejos inmunes asociados a tumores malignos y a lepra / Isolation and characterization of immune complexes associated with malignant tumors and leprosy

Hemos estudiado los complejos inmunes circulantes (CIC) asociados a diversas enfermedades tales como neoplasias malignas, lepra y artritis reumatoidea. Se realizó la detección de CIC empleando diferentes técnicas: test de combinación a 125I-Clq, a IgG radioactiva, a conglutinina bovina marcada, test de aglutinación de plaquetas y precipitado en polietilen glicol 3,5% y 2,5%. Posteriormente, se desarrollaron técnicas de asislamiento y separación de los CIC para la obtención de sus fracciones constituyentes en ciertos tumores malignos y en lepra, basadas en la afinidad de los CIC por proteína A y en la acción de diferentes buffers. Estos métodos se aplicaron previamente a complejos inmunes preparados in vitro (BSA-aBSA, OVA-aOVA, etc.). El análisis de las fracciones se realizó por SDS-PAGE, inmunoelectroforesis, inmunoblotting, etc. Los resultados fueron los siguientes: se observó una elevada incidencia de niveles de CIC positivos coincidentes con los estadios de actividad clínica, disminuyendo en la remisión. Así mismo en algunos grupos de pacientes los hallazgos de CIC permitieron evaluar la eficacia terapéutica. Con el desarrollo de técnicas de separación de CIC se obtuvieron fracciones inmunológicamente activas provenientes de los CIC aislados del suero de pacientes portadores de tumores malignos, especialmente del tubo digestivo y de mama y posteriormente en el suero de individuos con lepra. Los resultados obtenidos hasta la fecha han demostrado la utilidad clínica de los estudios... (AU)