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PubMed1992

Fluoxetine treatment of nonparaphilic sexual addictions and paraphilias in men.

BACKGROUND: Paraphilias (PAs) and non-paraphilic sexual addictions (NPSAs) may be behaviors that share a common perturbation of central serotonin neuroregulation as a component of their pathophysiology. Fluoxetine was selected as an agent that might mitigate these behaviors, based on the observations that PAs and NPSAs are associated with depression, compulsion, impulsivity, and disinhibited aggression. METHOD: Twenty men (PA, N = 10; NPSA, N = 10) recruited through newspaper advertisement were evaluated for depression and sexual behaviors at baseline and 4-week intervals while receiving fluoxetine pharmacotherapy in an open trial. Sixteen men completed the drug trial. Outcome was determined at 12 weeks using a single-factor, repeated-measures design and an analysis of variance. The general linear models procedure was used to test each of nine dependent measures. RESULTS: Nineteen (95%) of 20 men met non-exclusionary DSM-III-R criteria for dysthymia and 11 men (55%) met criteria for current major depression. At baseline, the paraphilic and the nonparaphilic subgroups were comparable in most intergroup measures of sexual function except total sexual outlet. PAs shared extensive comorbidity with NPSAs (100%). At outcome, statistically significant effects (p < .05) of fluoxetine were found in both groups over time for all variables pertaining to depression and PA/NPSA sexual behaviors. Statistically significant reduction in PA/NPSA response was evident by Week 4, while conventional sexual behavior was not adversely affected by pharmacotherapy. CONCLUSION: Men seeking treatment for PAs/NPSAs reported current depressive symptoms accompanied by a positive history of mood disorders, especially dysthymia and major depression. Fluoxetine selectively reduced both PA and NPSA behaviors in men reporting the presence of mild-severe depressive symptoms. Treatment response of PAs/NPSAs at outcome was independent of baseline depression score. Enhancement of central serotonin neurotransmission by fluoxetine may ameliorate symptoms of mood disorder, heightened sexual desire, and compulsivity/impulsivity associated with these conditions.

Adult↗

PubMed2004

Signature sequences in diverse proteins provide evidence for the late divergence of the Order Aquificales.

The Aquificales species are presently believed to be the earliest branching lineage within Bacteria. However, the branching order of this group in different phylogenetic trees is highly variable and not resolved. In the present work, the phylogenetic placement of Aquificales was examined by means of a cladistic approach based on the shared presence or absence of definite signature sequences (consisting of conserved inserts or deletions) in many highly conserved and important proteins, e.g. RNA polymerase beta (RpoB), RNA polymerase beta (RpoC), alanyl-tRNA synthetase (AlaRS), CTP synthase, inorganic pyrophosphatase (PPase), Hsp70 and Hsp60. For this purpose, fragments of the above genes that contained the signature regions were cloned from different Aquificales species (Calderobacterium hydrogenophilum, Hydrogenobacter marinus, and Thermocrinis ruber) and the sequence data were compared with those available from all other species. The presence in Aquificales species of distinctive inserts in Hsp70 and Hsp60 that are not found in any Firmicutes, Actinobacteria, or Thermotoga-Clostridium species excluded them from these groups of Bacteria. The shared presence of prominent indels in the RpoB (>100 amino acids), RpoC (>100 amino acids) and AlaRS (4 amino acids) proteins, which are only found in the various Aquificales species, the Chlamydiae, the CFBG (Cytophaga-Flavobacteria-Bacteroides-green sulfur bacteria) group, and Proteobacteria, strongly suggests their placement within these groups of Bacteria. A specific relationship between Proteobacteria and Aquificales is suggested by the presence in inorganic pyrophosphatase of a 2-amino-acid insert that is uniquely found in these phyla. However, the Aquificales species lacked a number of other protein signatures (e.g. indels in CTP synthase and Hsp70) that are characteristic of Proteobacteria, indicating that they constitute a distinct phylum related to Proteobacteria. These results provide strong and consistent evidence that the Aquificales diverged after the branching of Firmicutes, Actinobacteria, Thermotoga, Deinococcus-Thermus, green nonsulfur bacteria, Cyanobacteria, Spirochetes, Chlamydiae, and CFBG group, but before the emergence of the Proteobacteria.

Alanine-tRNA Ligase↗

PubMed2005

Ribosomal crystallography: peptide bond formation, chaperone assistance and antibiotics activity.

The peptidyl transferase center (PTC) is located in a protein free environment, thus confirming that the ribosome is a ribozyme. This arched void has dimensions suitable for accommodating the 3' ends of the A-and the P-site tRNAs, and is situated within a universal sizable symmetry-related region that connects all ribosomal functional centers involved in amino-acid polymerization. The linkage between the elaborate PTC architecture and the A-site tRNA position revealed that the A- to P-site passage of the tRNA 3' end is performed by a rotatory motion, which leads to stereochemistry suitable for peptide bond formation and for substrate mediated catalysis, thus suggesting that the PTC evolved by gene-fusion. Adjacent to the PTC is the entrance of the protein exit tunnel, shown to play active roles in sequence-specific gating of nascent chains and in responding to cellular signals. This tunnel also provides a site that may be exploited for local co-translational folding and seems to assist in nascent chain trafficking into the hydrophobic space formed by the first bacterial chaperone, the trigger factor. Many antibiotics target ribosomes. Although the ribosome is highly conserved, subtle sequence and/or conformational variations enable drug selectivity, thus facilitating clinical usage. Comparisons of high-resolution structures of complexes of antibiotics bound to ribosomes from eubacteria resembling pathogens, to an archaeon that shares properties with eukaryotes and to its mutant that allows antibiotics binding, demonstrated the unambiguous difference between mere binding and therapeutical effectiveness. The observed variability in antibiotics inhibitory modes, accompanied by the elucidation of the structural basis to antibiotics mechanism justifies expectations for structural based improved properties of existing compounds as well as for the development of novel drugs.

Animals↗

PubMedDate not supplied

AIDS-related knowledge, attitudes and behaviour in injection drug users attending a Toronto treatment facility.

Ninety injection drug users (61 males, 29 females) attending the Addiction Research Foundation Clinical Institute completed an anonymous, self-administered questionnaire about their knowledge, attitudes and behaviour regarding Human Immunodeficiency Virus (HIV) infection. Sixty-two percent had used drugs for more than five years; 61% used primarily heroin, 20% cocaine. Needle sharing was common: 76% within 5 years, 37% within the preceding month, although 87% named needle sharing as a risk factor for HIV infection. Current needle sharers could not be distinguished from former sharers on selected demographic, attitudinal or knowledge variables. Twenty percent of respondents had been HIV tested (all negative); 88% reported willingness to be tested. Thirteen percent would consider suicide or resume heavy drug use in response to a positive test; 19% were uncertain about their response. There may be a risk of serious harm to IDUs who are tested in the absence of excellent counselling and support services.

Academies and Institutes↗

PubMed1980

[Changes in the diastole time of the human heart as influenced by 4-6 weeks of physical training in ischemic heart disease].

On the basis of former investigations, the present study deals with the effects of a 4 to 6-week training, within the framework of a health resort treatment, on the following cardialogic parameters of persons suffering from ischaemic heart disease after myocardial infarction: heart rate, duration of systoles and diastoles (and, following from this, the variance of these quantities, the diastole/systole quotient, and the "diastolic volume per unit of time", i.e., the relative diastolic share per min). Since there is a very close correlation between the heart rate and the diastole, consideration is given to frequency-independent variabilities of these quantities. It can be shown that there is a frequency-dependent behaviour under load as compared to rest, when training, and in two different age groups. The diastole/systole relation and the diastolic volume per unit of time can give additional information concerning training results. But it is not yet possible, for the time being, to show all marginal and limiting conditions required for generalizing these conclusions. From the clinical point of view, the 104 patients included in the study can be considered as a relatively homogeneous group.

Coronary Disease↗

PubMed1995

Characterization of a new monoclonal antibody (PG-M3) directed against the aminoterminal portion of the PML gene product: immunocytochemical evidence for high expression of PML proteins on activated macrophages, endothelial cells, and epithelia.

PG-M3 is a new monoclonal antibody (MoAb) specifically directed against a peptide sequence located in the aminoterminal region of the human PML protein. PML gene fuses with the retinoic acid receptor alpha (RAR alpha) gene during the t(15; 17) chromosomal translocation of acute promyelocytic leukemia (APL). The epitope recognized by PG-M3 is species-specific and fixative-resistant and is shared by most PML isoforms and PML/RAR alpha fusion proteins. PML is consistently located within the nucleus, although a minority of cells (about 20%), both in vitro and in vivo, show positivity for PML also in the cytoplasm. The nuclear staining pattern of PG-M3 varies from speckled (cells other than APL) to micropunctate (APL cells). Although two physiologically expressed PML isoforms are detectable by immunocytochemistry only or predominantly in the cytoplasm of transfected cells, the cytoplasmic localization of PML is a property also shared by the PML isoforms that predominantly localize to the nuclei. Immunohistologic analysis of normal human tissues with the PG-M3 MoAb showed variable PML expression, with the highest levels of the protein in postmitotic, differentiated cell types, such as endothelial cells, epithelia, and tissue macrophages, especially activated ones. In keeping with this in vivo finding, PML appears strongly upregulated in the U937 promonocyte cell line after exposure to agents that induce monocyte/macrophage activation (interferon gamma) or maturation (vitamin D3 and transforming growth factor beta 1).

3T3 Cells↗

PubMed1993

The normal Huntington disease (HD) allele, or a closely linked gene, influences age at onset of HD.

We evaluated the hypothesis that Huntington disease (HD) is influenced by the normal HD allele by comparing transmission patterns of genetically linked markers at the D4S10 locus in the normal parent against age at onset in the affected offspring. Analysis of information from 21 sibships in 14 kindreds showed a significant tendency for sibs who have similar onset ages to share the same D4S10 allele from the normal parent. Affected sibs who inherited different D4S10 alleles from the normal parent tended to have more variable ages at onset. These findings suggest that the expression of HD is modulated by the normal HD allele or by a closely linked locus.

Adolescent↗

PubMed1993

Cloning and characterization of rabbit liver UDP-glucuronosyltransferase cDNAs. Developmental and inducible expression of 4-hydroxybiphenyl UGT2B13.

A polyclonal antibody generated against rabbit liver p-nitrophenol UDP-glucuronosyltransferase (UGT) was used to screen a rabbit liver cDNA expression library constructed in lambda gt11. A 500-base pair cDNA clone, termed pPNP, generated a fusion protein that was antigenic with the antibody. Clone pPNP encoded the 3' region of a UGT. To identify larger recombinants, clone pPNP was used as a probe to screen a second cDNA library constructed in lambda ZAP. Two different cDNA clones were identified by DNA sequence analysis. Based upon their predicted amino acid sequence analysis, the clones encode transferases belonging to the UGT2 subfamily, and have been identified as UGT2B13 and UGT2B14. The predicted N-terminal sequence of UGT2B13 is identical to that determined for the purified rabbit liver estrone UGT. However, expression of the UGT2B13 cDNA in COS-1 cells displayed no activity in the presence of estrone but efficiently conjugated 4-hydroxybiphenyl. Results of Southern blot analysis using the 5' divergent region of the UGT2B13 cDNA that encodes exon 1 demonstrates that multiple genes share sequence homology to UGT2B13, an observation which indicates that the estrone UGT and UGT2B13 genes are encoded by separate alleles. When the 5' variable regions of the cDNAs where used in Northern blot analysis, the expression of UGT2B13 and UGT2B14 were shown to be expressed primarily in adult rabbits. However, when neonatal rabbits were treated with either dexamethasone or rifampicin, UGT2B13 mRNA levels were induced. The neonatal induction of UGT2B13 mRNA corresponded with similar increases in 4-hydroxybiphenyl UGT activity. The expression and induction of UGT2B13 paralleled that of the developmentally regulated rabbit liver progesterone 6 beta-hydroxylase P4503A6.

Amino Acid Sequence↗

PubMed1993

Analysis of embryonic development with a model for under- or overdispersion relative to binomial variation.

Observations from a study of the development of ovulations into embryos for Texel sheep are analysed with a model for count data that are under- or overdispersed relative to binomial variation. The analysis is based on maximum quasi-likelihood (McCullagh and Nelder, 1989, Generalized Linear Models, 2nd edition, London: Chapman and Hall), following an approach suggested by Williams (1982, Applied Statistics 31, 144-148). The dispersion parameter is developed as a combination of a variance component representing shared maternal effects and a correlation, typically negative, between ovulations within ewes. The number of ovulations (the binomial denominator) is included as an explanatory variable.

Androstenedione↗

PubMed1984

Murine V kappa 25 and V kappa 27 amino-acid sequences of C57B1/6 origin: monoclonal antibodies 17S29.1 and 22S25.1 specific for the group A-streptococcal polysaccharide.

Antibodies 17S29.1 and 22S25.1 are monoclonal, hybridoma-derived gamma 3 kappa murine immunoglobulins with specificity for N-acetyl-glucosamine beta 1----3-linked to the L-rhamnose backbone structure, the immunodeterminant of the streptococcal Group A polysaccharide. The VL 17S29.1 amino-acid sequence is the third complete one reported from an antibody with this specificity, the second fully determined V kappa 25 structure and the first complete V kappa sequence of C57B1/6 origin derived from a carbohydrate-specific antibody. VL22S25.1 is a member of the V kappa 27 isotype of murine immunoglobulin VL regions. V kappa 17S29.1 and the determined part of the V kappa 22S25.1 sequence are compared to the previously described V kappa regions of streptococcal Group A polysaccharide-specific antibodies and to 12 selected partial and complete V kappa regions of antibodies with other specificities, predominantly to carbohydrate antigens. Both V kappa 17S29.1 and V kappa 22S25.1 increase the variability of known murine V kappa regions. They are the most homologous to the other V kappa regions derived from antibodies with streptococcal Group A polysaccharide specificity and share with them the amino-acid residue Arg74, so far characteristic for V kappa regions from antibodies with this specificity. The analysis of groups of independently expressed, highly homologous V kappa regions, namely V kappa 17S29.1 and V kappa 2S1.3 as one and V kappa 7S34.1 and V kappa 22S25.1 as a second group, offers the possibility of estimating the minimal number of V kappa germline genes involved in the immune response to the structurally defined streptococcal Group A polysaccharide antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkylation↗

PubMed1995

Comparative analysis by independent contrasts (CAIC): an Apple Macintosh application for analysing comparative data.

CAIC is an application for the Apple Macintosh which allows the valid analysis of comparative (multi-species) data sets that include continuous variables. Comparison among species is the most common technique for testing hypotheses of how organisms are adapted to their environments, but standard statistical tests like regression should not be used with species data. Such tests assume independence of data points, but related species often share traits by common descent rather than through independent adaptation. CAIC uses a phylogeny of the species in the data set to partition the variance among species into independent comparisons (technically, linear contrasts), each comparison being made at a different node in the phylogeny. There are two partitioning procedures--one used when all variables are continuous, the other when one variable is discrete. The resulting comparisons can be analysed validly in standard statistical packages to test hypotheses about correlated evolution among traits, to estimate parameters such as allometric exponents, and to compare rates of evolution. Previous versions of the package have already been used widely; this version is simpler to use and works on a wider range of machines. The package and manual are freely available by anonymous ftp or from the authors.

Data Interpretation, Statistical↗

PubMed1979

Shared N-terminal sequences in monclonal IgMkappa and IgGkappa proteins from a patient with a complex multiple paraprotein disorder.

The N-terminal sequence analyses were performed on the heavy (H) and light (L) chains of the idiotypically identical IgM kappa and IgG kappa paraproteins isolated from the serum of patient, Cam. The N-terminal 39 residues of the kappa chains of the IgM and IgG were identical and belonged to the human V kappa III subgroup. This sequenced stretch included the first L chain hypervariable region. The N-terminal 27 residues of the variable regions (VH) of the respective mu and gamma heavy chains were also identical and belonged to the human VHIII subgroup. These identical VH sequences were unique with lysine residues at positions 13 and 19. This dual lysine substitution has not been seen in 37 other human VHIII sequences reported in the literature. This N-terminal sequence homology in the V-regions of Cam IgM kappa and IgG kappa paraproteins and the shared idiotypy expressed by Cam IgM, IgG, and IgA proteins strongly suggest the existence of complete structural homology in the variable regions of the and L chains of these Ig molecules of three separate Ig classes. At the cellular and genetic level, these results point toward a common clonal origin for the idiotypically related Ig molecules and suggest that identical V-region (VH and VL) genes were utilized by the Cam lymphoid clone in the biosynthesis of the respective IgM, IgC, and IgA proteins.

Amino Acid Sequence↗

PubMed1991

Histologic transformation of follicular lymphoma to diffuse lymphoma represents tumor progression by a single malignant B cell.

To investigate the clonal relationship between follicular lymphoma (FL) and transformed diffuse lymphoma (tDL), we examined the expression of tumor idiotype, immunoglobulin (Ig) gene rearrangements and sequence of Ig variable genes in paired tissue specimens. All 16 cases analyzed expressed surface immunoglobulin (sIg) on both the FL and the tDL, though the immunophenotype of one case of FL could not be definitively determined. In 14 of 15 cases, the surface immunophenotype was preserved; the exception was likely secondary to a class switch from IgM to IgG. In 12 of 13 cases, antiidiotypic monoclonal antibodies prepared against the FL reacted with the paired tDL. Analysis of Ig gene rearrangements in four cases by Southern blot hybridization showed evidence of clonal relationships in all cases though concordance was not seen with all probes tested (C kappa, C lambda, JH, PFL1, and PFL2). In the one case that had a discordant L chain rearrangement, sequence analysis of the L chain demonstrated a common mature B cell origin for both the FL and tDL. To determine whether tDL arose from one or more FL cells, the sequences of the H chain variable genes were analyzed. Individual clones of the V region gene of the FL showed a random distribution of changes throughout the sequence. In contrast, individual clones of the V region gene from tDL shared numerous nonrandom sequence alterations, implying a common single cell origin. In conclusion, tDL is a mature B cell and arises by transformation of a single FL cell.

Antibodies, Anti-Idiotypic↗

PubMed1994

A common ancestry for multiple catalytic antibodies generated against a single transition-state analog.

Immunization with a single haptenic transition-state analog generates a few catalytic antibodies among the dozens of antibodies capable of binding the hapten. The diversity of the immune response has raised some fundamental issues, such as How do catalytic and noncatalytic antibodies differ on a structural basis? To address this issue, the variable region primary sequences of 11 antibodies (including 6 catalytic and 5 noncatalytic antibodies) elicited against a single haptenic transition-state analog were deduced from cDNA sequences. Cluster analyses using phylogenetic trees constructed by the neighbor-joining method have revealed that the amino acid sequences of noncatalytic antibodies bear no relationship to one another, while the catalytic antibodies share significant structural identity. Furthermore, no catalytic antibodies possessing amino acid sequences with high homology to those of noncatalytic antibodies were detected. Five catalytic antibodies examined showed 89-95% and 74-84% sequence homologies in the complete light- and heavy-chain variable regions, respectively. Thus, it seems likely that the catalytic antibodies elicited against a single hapten use the canonical set of variable region genes. Interestingly, one catalytic antibody showed only limited sequence similarity to the other catalytic antibodies and was found to exhibit a distinctly different substrate specificity. From the broad range of their binding constants to the hapten, it is unlikely that highly homologous catalytic antibodies are generated as a result of simple high-affinity choices. These results emphasize the utility of rationally designed transition-state analogs for the induction of antibody molecules with catalytic activity.

Amino Acid Sequence↗

PubMed2000

Three monoclonal antibodies to the VHS virus glycoprotein: comparison of reactivity in relation to differences in immunoglobulin variable domain gene sequences.

Three monoclonal antibodies (MAbs) to the VHSV G protein were compared in different immunoassays and the variable domain cDNA sequences from the respective immunoglobulin (Ig) genes were determined. One MAb (IP1H3) was non-neutralising and recognised different virus isolates equally well in ELISA. The other two were neutralising and recognised the same or closely related epitopes. One of these two MAbs (3F1H10) was more restricted in its ability to neutralise heterologous VHSV isolates than the other (3F1A2). A semi-quantitative relationship between binding of the two neutralising MAbs in ELISA and their neutralising activity was evident. Binding kinetic analyses by plasmon resonance identified differences in the dissociation rate constant (kd) as a possible explanation for the different reactivity levels of the MAbs. The Ig variable heavy (VH) and light (V kappa) domain gene sequences of the three hybridomas were compared. The inferred amino acid sequence of the two neutralising antibody VH domains differed by three amino acid residues (97% identity) and only one residue difference was evident in the V kappa domains. In contrast, IP1H3 shared only 38 and 39% identity with the 3F1A2 and 3F1H10 VH domains respectively and 49 and 50% identity with the 3F1A2 and 3F1H10 V kappa domains respectively. The neutralising antibodies were produced by hybridomas originating from the same fusion and the high nucleotide sequence homology of the variable Ig gene regions indicated that the plasma cell partners of the hybridomas originated from the same virgin B lymphocyte. The few differences observed in the VH and V kappa amino acid sequences were probably due to somatic mutations arising during affinity maturation and might explain the observed reactivity differences between the two MAbs.

Amino Acid Sequence↗

PubMed2000

The evolution of drug metabolism.

So-called 'drug-metabolizing enzyme' (DME) genes have existed on this planet for more than 2.5 billion years and would be more appropriately named 'effector-metabolizing enzymes'. Genes encoding DMEs have functioned in many fundamental processes in prokaryotes and, more recently, in countless critical life processes in plants and animals. DME genes exist in every eukaryotic cell and in most, if not all, prokaryotes. Over the past decade, it has become clear that each person has their own 'individual fingerprint' of unique alleles coding for DMEs. The underlying genetic predisposition of each patient reflects combinations of poor- and extensive-metabolizer phenotypes. If these enzymes cooperate in the same metabolic pathway for any given drug or environmental agent, such ecogenetic variability might be synergistic and could cause 30- to > 40-fold differences in activation or degradation. The end result can be large interindividual differences in risk of environmentally caused toxicity or cancer. Human DME gene polymorphisms often show high frequencies of variant alleles. Many factors contribute to persistence of these high frequencies, including a combination of selective pressures involving diet, climate and geography, as well as 'balanced polymorphisms' ('shared benefit' for the heterozygote). However, the extensive heterogeneity in the human genome currently being discovered suggests many more polymorphisms will occur not only in drug metabolism genes, but in all genes, and exhibiting large gene-by-gene variability.

Animals↗

PubMed1987

Complete variable region sequences of five homologous high affinity anti-digoxin antibodies.

High affinity murine A/J anti-digoxin monoclonal antibodies exhibit diversity in binding specificity for structurally related cardiac glycosides. They utilize several VH and VL genes. Among this diverse set, however, five antibodies share V region amino-terminal sequences that are remarkably homologous. The five antibodies were divided into three subsets based on different fine specificity-binding patterns. Therefore, complete V region sequences were determined by Edman degradation and by nucleotide sequence analysis. The VH region homology among the five antibodies was 84 to 100% and the VL region homology was 89 to 99%. The sequence data are consistent with the use of single (or closely related) VH and VL genes encoding the five antibodies. Four antibodies, derived from the same fusion (40-40, 40-120, 40-140, and 40-160), use identical D, JH2, and JK5 gene segments and identical junctions suggesting that they are clonally related. The fifth antibody (35-20) uses different D and JH1 gene segments but the same JK5 gene segment. All five antibodies share a cross-reactive idiotype. The three antibodies that exhibit the greatest degree of homology (40-40, 40-120, and 40-140) also share indistinguishable antigen-binding patterns as well as private idiotopes not present on the other two antibodies. Antibody 40-160, which has the next most homologous sequence, shares idiotopes with the first set but binds preferentially to different sites on the hapten, whereas antibody 35-20 has the most divergent sequence. In general, the degree of sequence homology among the five antibodies correlates with their hierarchical order based on hapten and idiotype fine specificity patterns.

Amino Acid Sequence↗

PubMed1994

Identification in human ovarian follicular fluid of proteins that share an epitope region unique to the extracellular domain of the follicle-stimulating hormone receptor.

Recently we identified a unique region, residues 9-30 in the extracellular domain of the FSH receptor, capable of binding FSH but not LH or TSH. We have shown that polyclonal antibodies raised against this region specifically recognized intact FSH receptors present on plasma membranes of cultured rat Sertoli cells. In the present study, plasma membranes from human granulosa-lutein cells were solubilized and subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis, followed by Western blot analysis. Antireceptor peptide antibody, but not preimmune serum control, recognized intact human FSH receptors, suggesting that human and rat FSH receptors share this unique N-terminus epitope region. Recent cloning studies have identified, in addition to full length receptor, the presence of FSH receptor-spliced messenger RNA variants, which encode receptor proteins with variable lengths of hydrophilic extracellular domains, but lacking transmembrane domains. Such proteins could theoretically represent secreted forms of the receptor. In this study, we used a polyclonal anti-FSH receptor (residues 9-30) peptide antibody to investigate whether FSH receptor-related soluble proteins might also be present in human ovarian follicular fluid (FF). In an enzyme-linked immunosorbent assay specific for the FSH receptor, antireceptor peptide antibody, but not preimmune serum serving as control, identified significant immunoreactivity in several human ovarian FF samples, suggesting that protein(s) present in FF share a common epitope with the extracellular domain of the FSH receptor. The apparent levels of FSH receptor-related activity in FF samples, expressed relative to the FSH receptor (residues 9-30) peptide, ranged from 31-55 ng/mL. Passing of the samples through 0.22-micron filters or subjecting the samples to high speed centrifugation did not alter the activity profiles of the samples ruling out effects due to contamination with plasma membranes from granulosa cells. When human FF samples were subjected to gel permeation chromatography, at least four distinct protein peaks were resolved, in the molecular mass range between 70-460 kilodaltons, each of which was recognized by the FSH receptor 9-30 peptide antibodies. Our results provide initial evidence for the presence in human ovarian FF of proteins sharing epitope with the extracellular domain of the FSH receptor and presumably derived from the granulosa cell. Since we have previously shown that the epitope region, represented by residues 9-30 in the extracellular domain of the FSH receptor specifically binds FSH, the proteins in human FF sharing this epitope may have functional significance.

Amino Acid Sequence↗