Virus de papiloma humano: Revisión e indicaciones terapéuticas / Human papillomavirus: Review of the different therapeutic modalities

La infección por virus de papiloma humano constituye una de las más frecuentes enfermedades de transmisión sexual. Dentro de los más de 100 tipos de virus descriptos hasta el momento, varios de los mismos son capaces de inducir transformación maligna de las células huésped. El presente trabajo consiste en una revisión de las diferentes modalidades terapéuticas utilizando una estrategia de medicina basada en evidencia.

The infection by human papillomavirus is one of the most frequent sexually transmitted diseases. Among more than 100 types of HPV described, several are capable of inducing malignant transformation in host cells. This work intend to review the different therapeutic modalities using an evidence based medicine strategy.

Evaluación de diferentes procedimientos de detección de anticuerpos anti Ro/SS-A 52 kDa y anti-Ro/SS-A 60 kDa en síndrome de Sjögren primario / Evaluation of the different procedures in the detection of anti RO/SS-A 52 kDa and anti-RO/SS-A 60 kDa antibodies in primary Sjögren's syndrome

Un grupo de pacientes con Síndrome de Sjögren primario fue analizado en el presente trabajo con el fin de evaluar diversas técnicas para la determinación de autoanticuerpos anti-Ro/SS-A de 52 y 60 kDa. Las técnicas evaluadas fueron: doble inmunodifusión en geles de agarosa utilizando como antígeno un extracto de bazo humano; enzimoinmuno análisis (ELISA) y Western Blot ambos realizados utilizando antígenos proteicos recombinantes (Ro/SS-A 52 y 60 kDa en ensayos individuales) como antígenos. Si bien las técnicas de ELISA y Western Blot poseen una mayor sensibilidad que la inmunodifusión, en ciertos casos esta última no puede ser completamente reemplazada por las primeras. Hay que tener en cuenta la naturaleza del antígeno utilizado para poder sacar conclusiones. Los antígenos recombinantes pueden mantener los epitopes lineales y conformacionales de las moléculas nativas, pero carecen de la interacción con las demás moléculas formadoras del complejo. En cambio, en el extracto antigénico utilizado en la inmunodifusión se podrían mantener epitopes formados por la interacción entre las distintas moléculas del complejo RoRNP. Nuestros resultados indican que, a pesar de su mayor sensibilidad, las técnicas de ELISA y Western Blot no serían capaces de desplazar totalmente a la inmunodifusión en geles (AU)

Antibodies from patients with psoriasis recognize N-acetylglucosamine terminals in glycoproteins from Pityrosporum ovale.

We have previously reported the finding of circulating antibodies recognizing two proteins of 100 and 120 kD (PO100 and PO120) from Pityrosporum ovale in patients with psoriasis. These antibodies were specific, since they were not detected in normal sera nor in other diseases linked to P. ovale such as seborrhoeic dermatitis or pityriasis versicolor. The present study aimed at further characterizing the specificity of these antibodies. Enzyme-labelled lectins were used to determine the carbohydrate composition of PO120 and PO100. BSII, a lectin that recognizes terminal N-acetylglucosamine (GlcNAc), showed the same banding pattern as sera from patients. Reactivity against these proteins was inhibited after mild oxidation of the carbohydrate moieties of the extract. Treatment of the extracts with lyticase altered the immune reactivity against the PO120 band as seen in Western blot assays. PO100 was not detected after lyticase digestion. Digestion with lysozyme did not alter the immune reactivity of the PO100 and PO120 bands, although the protein pattern in SDS-PAGE was modified. To examine the relevance of anti-GlcNAc antibodies in the immune response to P. ovale in psoriasis, we performed a binding inhibition ELISA. Psoriatic sera that were positive in the ELISA against a heat-denatured extract of P. ovale were rendered negative only by pre-incubation with GlcNAc in a concentration-dependent manner. Our results are indicative that the antibody response to PO100 and PO120 in patients with psoriasis is directed towards terminal GlcNAc residues.

The frequent mutation Gly/Asp in CDR1H may determine a cross-reactive idiotope in anti-I cold agglutinins.

Variable domains (VH) of all known anti i/I cold agglutinin (CA) heavy chains are codified by the VH4-21 gene. While anti-i CAs are the expression of gene rearrangement without mutations represented by amino acid changes, anti-1 CAs present, among others, a frequent somatic mutation of Gly by Asp at position 31. The hydropathy profile calculated for the CDR1H (position 30 to position 35), as well as some adjacent positions of the heavy chain belonging to anti-i and anti-I antibodies, showed the conformational changes accompanying the replacement of Gly by Asp. A MoAb (LP91), which had been obtained in BALB/c mice immunized with a Fabmu fragment from a monoclonal IgMkappaIIIb anti-I CA (protein KAU), proved capable of inhibiting human adult erythrocyte cryoagglutination by anti-I CAs but not that of fetal erythrocytes by anti-i CAs. Western blot analysis disclosed that such MoAbs recognized a sequential epitope located in the Fd fragment of all anti-I CAs employed in this study. With the purpose of checking whether Asp(31) was involved in the epitope recognized by the MoAb, two peptides, D and G, were synthesized which mimicked the CDR1H structure of anti-I and anti-i, respectively; the MoAb only reacted with peptide D by ELISA. Subsequent experimental results indicate that the Gly/Asp mutation could be associated with the diverse specificity presented by these autoantibodies, a change determining a characteristic epitope/idiotope, recognized by LP91 in the CDR1H.

Characterization of the lipase activity of Malassezia furfur.

Enzymes capable of metabolizing lipids are essential for the growth of Malassezia furfur in vitro and in vivo. We designed a series of experiments to characterize the lipolytic system in this yeast. The optimal pH of the lipase system was 7.5 Lipase activity was detected in soluble and insoluble saline cell extracts and in supernatant from the cultures. Esterase activity screened in samples separated by native polyacrylamide gels showed that it was restricted to one band of low mobility. An FPLC analysis of the soluble saline extract demonstrated that the lipase activity was present in three major peaks with different protein composition as revealed by SDS-PAGE. The enzymatic activity and cell growth were first induced and later inhibited by increasing concentrations of polyethylene-sorbitan-monooleate (Tween-80). The characterization of the lipolytic system (e.g. its induction by substrate and the effect of pH and/or different cations) could help to explain the increment in the number of M. furfur infections related to alterations of surface lipids in the skin such as seborrheic dermatitis.

N-glycanase treatment of F(ab')2 derived from asymmetric murine IgG3 mAb determines the acquisition of precipitating activity.

The aim of this study was to analyse four anti-DNP asymmetrically glycosylated monoclonal IgG3 antibodies (194/2, 194/5, 194/6 and 194/12) before and after carbohydrate manipulation. Microheterogeneity in the composition of the carbohydrate moiety involved in Fab' glycosylation was detected using lectins. Additional O-glycosidic carbohydrate chains were detected within the Fc region of two monoclonal antibodies. Fab' glycosylation produced a difference in the binding constants (Ka) in each paratope of two orders of magnitude, as determined by means of primary ligand-antibody interaction. The difference in binding affinity and the importance of Fc-Fc interaction was evidenced by a lack of BSA-DNP precipitation by the F(ab')2 fragments. The oxidation of the antibodies with sodium periodate caused the disappearance of the low affinity binding site as determined by fluorescence quenching. Furthermore, the enzymatic removal of the carbohydrate with N-glycanase determined the acquisition of precipitating activity by the F(ab')2 fragments.

Antibodies to proteins from Pityrosporum ovale in the sera from patients with psoriasis.

In order to analyse the humoral immune response to the commensal yeast Pityrosporum ovale, we developed a western immunoblot technique with a salt soluble extract of P. ovale cytoplasm. In the present study, we tested sera from patients with psoriasis (n = 15), seborrhoeic dermatitis (n = 10), pityriasis versicolor (n = 8), and normal controls (n = 10). Seventy-three per cent (11/15) of the patients with psoriasis showed specific reactivity with a protein derived from P. ovale of estimated molecular mass 120 kDa, and 46% (7/15) of the cases recognized a 100-kDa protein. Sera from pityriasis versicolor and normal donors showed nonspecific reactivity with several bands of lower molecular weight. To characterize the location of the 100 and 120-kDa proteins, we performed a lyticase digestion of the cell wall, and analysed the soluble digested products by western blotting. The sera from psoriasis patients detected several bands in the range 100-120 kDa. The finding of the immunoreactive 120-kDa protein in this fraction suggests its location at the space between cell wall and membrane (periplasmic space). As a control, we performed an extraction of the cytoplasmic proteins of the dimorphic yeast Candida albicans. C. albicans showed a different pattern of banding in SDS-PAGE. Immunoblots with C. albicans did not allow the detection of any related band. A smear was observed in the high molecular weight range consistent with the presence of lipopolysaccharides. The role of the immune response in infection by P. ovale has not yet been fully explored.(ABSTRACT TRUNCATED AT 250 WORDS)

Hereditary angioedema: therapeutic effect of danazol on C4 and C1 esterase inhibitors.

Hereditary angioedema (HAE) is an inherited deficiency of C1 esterase inhibitor (C1 inh). The two types of genetic C1 inh deficiency are type I, which is quantitative, and type II, which is functional. For the purpose of the present study, four HAE patients were selected. None of them had received any androgenic therapy. The group included three type I and one type II cases. All patients that entered the protocol received danazol, 400 mg/day for 14 days. The complement system was evaluated by monitoring C4, hemolytic complement 50% (CH50), circulating immune complexes (CIC), and antigenic and functional C1 inh during the study. The level of complement factors at the beginning and at the end of this period demonstrated a statistically significant increase in C4 and CH50 and the disappearance of CIC, while C1 inh remained unmodified. These results suggest that the therapeutic effect of danazol may have two mechanisms of action: (1) promotion of C4 synthesis by anabolic effect resulting in an improvement of the complement system with the disappearance of CIC and (2) a minor increase in C1 inh level primarily due to the lack of its consumption.

[Hereditary angioedema. Effect of danazol on C4 and functional C1INH]. / Angioedema hereditario (AEH). Acción del danazol sobre el C4 y C1INH funcional.

Hereditary angioedema (HAE) is an inherited deficiency of the inhibitor of C1 esterase (C1 inh). Two types of genetic C1 inh deficiency have been described, type I: quantitative, and type II: functional. For the purpose of the present study, 4 out of 51 HAE patients were selected. None of them had received any previous androgenic therapy. The group was integrated by two type I and one type II cases. All patients that entered in the protocol received 400 mg/day of danazol over 14 days. The complement system was evaluated by monitoring C4, Hemolytic complement 50% (CH50), Circulating Immune Complexes (CIC), and antigenic and functional C1 INH during the study. The level of the complement factors at the beginning and the end of this period demonstrated a statistically significant increase of C4 and CH50 and the disappearance of CIC, while C1INH remained unmodified. These results suggest that the therapeutic effect of Danazol may have two mechanisms of action: i. promotion of C4 synthesis by anabolic effect resulting in an improvement of the complement system with the disappearance of CIC, and ii, a minor increase of C1 inh level primarily due to the lack of its consumption.

[Immunopathogeny of pemphigus]. / La inmunopatogenia de los pénfigos.

This article reviews recent concepts of pathogenetic mechanisms in pemphigus. We describe the pathogenic effect of the autoantibodies, the animal model for the disease and the ultrastructural alterations which follow the antibody-antigen interaction. The role of complement and protease systems in development of tissue injury are also discussed.

[Structure of the dermo-epidemic junction]. / Estructura de la unión dermoepidérmica.

The basement membranes are extracellular proteic matrixes involved mainly in cell-substrate interactions. The dermo-epidermal junction (DEJ) is defined as the region formed by the dermal pole of the basal cell layer, the intercellular spaces, the lamina densa or basal lamina and the acellular fibrous components of the papillary dermis. The functions of the DEJ are to bind the epithelia to the connective tissue, and to preserve the viability of the epidermis by means of connecting it to the dermis. which is in charge of providing the necessary nutrients for its normal proliferation. The purpose of the present communication is to provide a concise review of the recent knowledges about the ultrastructure of the DEJ, with special emphasis on its antigenic components.

[Hereditary angioedema: changes in serum levels of C4 in response to danazol]. / Angioedema hereditario: variaciones de los niveles séricos de C4 en respuesta a danazol.

12 patients (7 males and 5 females) suffering from the common form of HAE were included in the study protocol. All patients were older than 18 years. They were evaluated Cl INH, C4, Clq, Cls, C3, C5, C8, Bf, CH 50% and CIC. For the purpose of the study they were only considered Cl INH, C4, CH 50%, CIs and CIC levels. The rest of the complement components were among normal values. Data were recorded at day 0 and after 10 days on treatment with 400 mg/day of Danazol. Results were as follows: 50% of the patients had CIC when CH 50% values were below 120 U/ml., after treatment CIC disappeared and CH 50, Cls, C4 and Cl INH increased significatively. C4 seemed to increase more and quicker than Cl INH in terms of absolute values. We postulate that in the group of patients with CIC, the primary cause of the disease may be an alteration in C4 synthesis and that Cl INH may be lowered because of its consumption. We postulate that Danazol could act in these cases stimulating C4 synthesis independently or in accordance with Cl INH.

Hereditary angioedema: preliminary report on skin biopsy finding of fibrin and/or C4 through immunofluorescence.

Hereditary angioedema is considered an inherited disorder of the complement system, manifested by repeated crises of angioedema involving the skin, the gastrointestinal and respiratory tracts. Biopsies of normal skin obtained from 5 patients, diagnosed with hereditary angioedema, were found to be positive for fibrin and in one case also positive for C4. The sections stained with anti-fibrin serum showed fibrin deposits around isolated epidermal cells, while C4 staining revealed a homogeneous pattern along the epidermis. Fluorescence patterns and laboratory findings before and after treatment with danazol and/or anti-fibrinolytic treatment are reported.

Hereditary angioedema: polymorphism.

Four patients with hereditary angioedema were studied. All had low values of C4, C1 INH, (CH 50) complement activity and circulating immune complexes. This report takes into account the different aspects that this disease can present, often quite different from the classical description of hereditary angioedema.