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The relationship between attachment styles and Cluster B personality disorders in prisoners and forensic inpatients.

The relationship between attachment styles and Cluster B personality disorders were examined among prisoners, forensic inpatients and controls from the general population. Forensic inpatients and prisoners reported significantly less frequently the secure attachment style (Relationship Questionnaire) and significantly more the fearful attachment style compared to the normal controls. Both forensic groups could not be distinguished from each other. Further, prisoners, forensic inpatients and controls could not be differentiated on the basis of the dismissing nor the preoccupied attachment style. With respect to personality pathology, almost all relationships between Cluster C pathology, on the one hand, and attachment styles, on the other, were significant. Cluster A pathology was clearly related to the secure and fearful attachment style. With respect to cluster B pathology, the results were more specific but also less clear. The results were strongly dependent on the way the personality pathology variables were treated, as either categorical or dimensional. None of the cluster B personality pathology variables were associated with the fearful attachment style and histrionic personality pathology was negatively associated with the dismissing attachment style. Antisocial personality features were associated with a dismissing attachment style. Borderline personality pathology, when treated as a categorical variable, was significantly related to the preoccupied attachment style. These results show that (1) cluster A and cluster C pathology are more strongly associated with attachment than cluster B, (2) treating personality data as either dimensional or categorical is of major importance to the conclusions that can be drawn, (3) it is important to control for the influence of co-morbid personality pathology when examining the relationship between (Cluster B) personality pathology and attachment.

Adult↗

Toward the next quarter-century: conceptual and methodological challenges for attachment theory.

Attachment theory and research have offered fundamental insights into early sociopersonality development for the past quarter-century. As its scope expands throughout the life course with applications to developmental psychopathology, however, attachment work faces important conceptual and methodological challenges. These include (a) expanding Bowlby's theoretical formulations to address developmental changes in the nature of attachment organization beyond infancy, the converging influence of multiple attachment relationships, and the nature and development of internal working models: (b) systematically validating assessments of attachment security for older ages in the context of enhanced theoretical understanding of how attachment itself changes with age; (c) new methodological approaches to understanding the relations between attachment and later behavior in light of empirical evidence of stability and change in attachment security and the need for explicit theoretical predictions of the sequelae of attachment security; and (d) more complex conceptualizations of the associations among attachment, contextual risk, and later behavior. These are similar to the challenges facing the original pioneers of attachment theory and research, suggesting that familiar problems must now be reconsidered against the landscape of new applications of attachment work and the insights of contemporary developmental science.

Child↗

Attachment patterns across multiple family relationships in adulthood: associations with maternal depression.

We explored attachment in a family context by applying family systems principles to the investigation of multiple attachment relationships within families. This study focused on maternal adult attachment with respect to family of origin experiences (assessed using the Adult Attachment Interview [AAI]) as well as maternal marital attachment (assessed using the Marital Attachment Interview [MAI]). We examined associations between maternal adult attachment (or marital attachment) and three levels of family functioning including individual maternal depression symptoms, dyadic marital satisfaction (reported by mothers), and family unit functioning. We also examined associations between combined attachment security (consistent secure, AAI secure/MAI insecure, AAI insecure/MAI secure, and consistent insecure) and family outcomes. Finally, we assessed the extent to which attachment representations operate differently in the context of family stress, namely maternal depression. We found that attachment security with respect to particular relationships was differentially associated with different levels of family functioning. Examination of the security of combined adult and marital attachment further supported the multilevel organization of the family system.

Adult↗

Children's ability to delay gratification: longitudinal relations to mother-child attachment.

Concurrent and longitudinal mother-child attachment qualities were studied in relation to children's ability to postpone gratification at age 6 years. A sample of 32 children (at ages 12 months and 18 months) and their mothers participated in the strange situation procedure. At age 6 years, they were observed in an attachment situation and administered a standard delay of gratification task. The length of time that children were able to delay gratification at age 6 was predicted both by concurrent attachment quality and by a longitudinal attachment measure. Children with secure attachment were able to wait the longest periods of time, whereas those with insecure-disorganized attachment had the most difficulties in waiting. The effects of longitudinal, but not concurrent, attachment quality on children's total waiting time remained significant when other important variables were considered, including gender and children's cognitive functioning. An interactive effect was found between attachment quality and cognitive functioning. Insecure-avoidantly attached children with high cognitive functioning did not differ in their overall waiting times from securely attached children, but insecure-avoidantly attached children with average or low cognitive functioning did have shorter waiting times. The study provides a basis for the further investigation of mother-child attachment quality as a factor that is linked to children's delay behavior.

Attention↗

Implications of attachment theory and research for developmental-behavioral pediatrics.

This article presents a basic overview of attachment theory, concepts, and research. The review includes a discussion of the nature of the attachment relationship, its origins in human evolutionary history, and common misconceptions about attachment. We describe phases in the development of attachment relationships and review research on factors that influence attachment variations. We discuss the implications of variations in early attachment relationships for later development (adaptation and maladaptation). And finally, we review briefly the implications of attachment theory and research for pediatric practice. Some key points are that (1) virtually all infants become attached to caregivers regardless of quality of care; (2) attachment relationships evolve in phases over time; (3) children with disabilities form attachment relationships in ways comparable to nondisabled children but manifest attachment somewhat differently; (4) the consequences for attachment of out-of-home care, separations, and significant disruptions (e.g., adoption) depend on timing and circumstances; (5) many infant regulatory difficulties, as well as child behavior problems, originate in the caregiving relationship; and finally, (6) change in parent-child relationship disturbances is complex and requires time and effort.

Caregivers↗

Prevalence of horizontal attachment loss in extracted teeth.

OBJECTIVE: Probing attachment level provides useful information on patterns of destruction of the periodontium. It is difficult to detect complex attachment loss in clinics. The purpose of this study was to estimate prevalence of vertical and horizontal attachment loss in extracted teeth. MATERIAL AND METHODS: We collected 10,212 extracted teeth from 130 dentists in Japan. After staining of periodontal membrane with erythrosine, linear loss of vertical and horizontal attachment was measured using a digital caliper. RESULTS: Mean vertical attachment loss varied from 5.3 to 8.6 mm. Incisors had severe attachment loss at mesial sites. Specific local attachment loss at palatal sites was observed in maxillary premolars and molars as well as in mandibular canines and premolars. Horizontal attachment loss was observed in 23% of the teeth. Frequency of horizontal attachment loss of > or = 2.1 mm was 6.4%. CONCLUSION: Severe attachment loss was observed on the palatal side of maxillary premolars. More than 1/3 of the maxillary first molars showed horizontal attachment loss. It may be impossible to debride 6.4% of teeth in cases of severe periodontitis because horizontal attachment loss may be deeper than the curette blade length.

Humans↗

Application of attachment theory for psychological support in palliative medicine during the terminal phase.

BACKGROUND AND PURPOSE: The situation leading to the death of a close relative is a unique and irrevocable experience of separation which evokes a state of emotional strain for the patient and the family. This situation therefore is an especially effective trigger of the so-called 'attachment system'. Attachment research in recent decades has shown that already in early infancy every person develops special attachment strategies activated in cases whenever a person cannot cope on its own with dangers. Only four such patterns of attachment have been specified, namely 'secure', 'insecure-avoidant', 'insecure-ambivalent/enmeshed' and 'disoriented/disorganized'. Since the dying are usually brought to the hospital by members of the family, the doctor responsible for treatment can perceive with unusual clarity the patterns of attachment within the family system, and can integrate such observation into her treatment strategy. This article suggests an attachment-informed therapy in the field of palliative medicine. It seems apparent that such approaches provided by the attachment theory for relief during the terminal phase are not only relevant in a palliative context but also applicable within the overall field of medicine and care-giving relating to terminal patients and their families. METHODS: To the doctor familiar with the attachment patterns and the conditions of their formation, clinical observation easily reveals which pattern is active among the dying and the accompanying members of the family. Here, cases are used to show how these insights can be realized in the psychotherapeutic care of patients and their families on a palliative ward. For example, in a case of 'avoidant' attachment, denied emotions can be addressed carefully and still existent hopes for protection and support can be reinforced; in a case of so-called 'ambivalent-enmeshed' attachment, overly intense relationships can be disentangled, and in a case of 'disorganized' attachment, emotion regulation can be supported and clarity in the relationships can be promoted. RESULTS: The clinical results show that psychotherapeutic intervention based on insights imparted by the attachment theory are of special benefit in relieving the psychological strain for the dying and their families.

Aged↗

Measuring adult attachment representation in an fMRI environment: concepts and assessment.

Human attachment is defined as a biologically based behavioral system that influences motivational, cognitive, emotional, and memory processes with respect to intimate relationships (parents, life partner, own children). Recent neurobiological studies in this field have in common that they investigated social relationships by examining fMRI neuroimaging patterns while individuals viewed pictures of their beloved relationship partner versus friends, acquaintances, strangers, or mothers' responses to their young children. The researchers showed that the neural underpinnings of these unique intimate emotional states are linked to functionally specialized areas in the brain. Conceptualizing this work from a behavioral systems-attachment theory perspective, these studies did not directly address the subject's attachment representational system. Traditional attachment theory and research has been built on the analysis of attachment narratives, called 'attachment representation'. The Adult Attachment Projective developed by George and West in 2001 is a set of attachment-based schematic pictures. It is constructed to increasingly activate the participant's attachment system in the course of the task, that is, by the introduction of increasingly stressful attachment scenes concluding with pictures of individuals facing death and potential abuse alone. The attachment patterns are evaluated based on individuals' overall verbal response to the picture set. This paper proposes that the AAP is a fruitful measure to use in an fMRI environment to examine brain activation patterns in adults while they are speaking overtly about attachment stories in a standardized setting.

Adult↗

A new method for quantifying the complexity of muscle attachment sites.

Muscle attachment site morphology may have valuable use for reconstructing activity patterns in individuals from historic populations or extinct species. The skeletal locations where muscles and tendons attach are morphologically very complex, and variations in this morphology may reflect stresses experienced by these attachment sites as a result of muscular contractions. However, existing methods for assessing attachment site complexity are qualitative and subjective. This article describes a new method for quantifying attachment site complexity in which attachment sites are scanned with a 3D laser scanner and the morphological complexities of their surfaces are quantified using fractal analysis. The method described here documents the complexity at specific transects along six limb attachment sites in adult female sheep (Ovis aries), and variations in complexity within attachment sites are explored. Overall trends indicate that most of the attachment sites examined here are more complex at their peripheries than at their centers, indicating that these sites experience more varied loads at the peripheries of the tendon attachments. Exceptions to this trend are noted and all functional implications are discussed. This method provides the first opportunity to explore variations in morphological complexity within attachment sites. Assuming a relationship between tensile strains and bony morphology exists, this method provides a new tool to explore the strain environments of muscle attachment sites.

Anatomy↗

Integrin-mediated attachment of articular chondrocytes to extracellular matrix proteins.

OBJECTIVE: To investigate the interactions between chondrocytes and their extracellular matrix (ECM). An attachment assay was used to determine the extent of integrin-mediated attachment of chondrocytes to a variety of ECM proteins and the effect of monolayer culturing on attachment activity. METHODS: Bovine and human articular cartilage chondrocytes were grown in high-density monolayer cultures for 3-21 days and used in the assays. Cell shape and production of 3H-proline-labeled collagen were monitored to assess phenotypic changes with time in culture. Cultured chondrocytes were incubated in wells coated with purified proteins, with and without specific inhibitors of integrin-mediated attachment, and cell attachment was determined. RESULTS: Compared with bovine serum albumin, chondrocytes showed significant attachment to fibronectin, matrix Gla protein (MGP), osteopontin, bone sialoprotein II (BSP II), vitronectin, and types II and VI collagen. A synthetic peptide containing the integrin-recognition sequence Arg-Gly-Asp inhibited attachment to all the proteins tested, except types II and VI collagen. A monoclonal antibody (MAb) to the beta 1-integrin subunit inhibited attachment to fibronectin, MGP, and type II collagen, and a MAb to the beta 3-integrin subunit inhibited attachment to BSP II and osteopontin. An increase in cell attachment was seen with time in culture, and this increase was followed by a change in the chondrocytes to flattened, type I collagen-producing cells. CONCLUSION: Chondrocytes can attach to a variety of cartilage and bone proteins; this attachment is mediated via integrins, including members of both the beta 1 and beta 3 subunit families. The modulation of the chondrocyte phenotype during monolayer culture may be related to activation or increased expression of integrins.

Animals↗

Attachment to extracellular matrix molecules by cells differing in the expression of osteoblastic traits.

Two sets of clonal cell populations differing in the expression of osteoblastic traits, the rat osteosarcoma cell lines ROS 17/2.8 and ROS 25/1 and the immortalized fetal rat calvarial cell lines RCT-1 and RCT-3, were compared for their ability to attach to a series of extracellular matrix (ECM) constituents in vitro. Both osteoblastic (ROS 17/2.8, RCT-3) and nonosteoblastic (ROS 25/1, RCT-1) cell lines attached in a time- and concentration-dependent manner to plates coated with fibronectin (FN), osteopontin (OP), type I collagen (Col I), type IV collagen (Col IV), and laminin (LN) but only weakly to osteocalcin (OC) and thrombospondin (TSP). In both systems, the osteoblastic and nonosteoblastic clones attached identically to FN. Both ROS 17/2.8 and ROS 25/1 attached to similar molar amounts of substrate with the same preference order: FN > LN > Col I > or = Col IV. Maximal ROS 17/2.8 attachment to OP was > or = Col I but required approximately 2.5 times more substrate. ROS 25/1 attached less effectively than ROS 17/2.8 to most non-FN substrates. RCT-3 cells attached similarly to ROS 17/2.8 except that the preference order for Col I and LN was reversed and attachment to OP was lower than for ROS 17/2.8 RCT-1 cells attached best to Col I rather than FN, and equaled or surpassed RCT-3 in attachment to other non-FN substrates. Thus in these experimental systems, cells expressing an osteoblast-like phenotype exhibited generally similar ECM attachment properties. Their nonosteoblastic counterparts recognized the same spectrum of ECM constituents but differed from the osteoblastic cells and from each other in the effectiveness of their attachment to substrates other than FN.

Animals↗

Substrate-attached serum and cell proteins in adhesion of mouse fibroblasts.

The effects of serum and coatings of substrate-attached material (SAM, which remains tightly adherent to the substrate after EGTA-mediated removal of cells) on the kinetics of attachment of DNA-radiolabeled BALB/c 3T3. SV40-transformed 3T3, and concanavalin A-selected revertant cells to glass coverlips were studied. The presence of serum in the medium of attaching cells had a marked effect on (1) the initial time lag before stable attachment of cells, (2) the maximum level of attached cells, (3) the stability of attachment, and (4) pseudopodial spread of the cell over the substrate. These serum effects could be mimicked by measuring attachment in medium without serum and with use of serum-preadsorbed or 3T3 SAM-coated coverslips. Enzymatic treatment of serumpreadsorbed substrates indicated that the factor(s) in serum which affects attachment is very trypsin-sensitive. Serum preadsorption of substrates stimulated attachment of SVT2 cells in medium with serum in a manner very similar to the effects of 3T3 SAM coating, while attachment of 3T3 SAM coating, while attachment of 3T3 or revertant cells was unaffected. Slab gel electrophoretic analysis (PAGE-SDS gels) identified eight major serum proteins by Coomassie blue staining (a) which bind to the substrate in the absence of cells and (b) which persist on the substrate after growth to confluence of 3T3 or SVT2 cells; this suggests that major breakdown or serum-adsorbed components does not occur during growth of normal or transformed cells. Seven radioactive SAM proteins were detected by autoradiography in 3T3 or SVT2 SAM electropherograms -- two of which are high molecular weight components which correspond to the glucosamine-radiolabeled hyaluronate proteoglycans observed previously; the remaining five are newly-identified proteins in SAM (one of these proteins appears to be actin). 3T3 and SVT2 cells have unique proportions of these seven components. The data are consistent with the idea that normal or virus-transformed cells do not attach directly to the culture substrate, but to specific classes of substrate-adsorbed serum proteins via deposition of specific classes of cell surface proteins and polysaccharides.

Actins↗

Modification of integrin-mediated cell attachment to substrata by serine proteinases in the presence and absence of divalent cations.

The sensitivity to serine proteinases of cellular proteins involved in cell-matrix adhesion was investigated using C32 melanoma cells. Cells dissociated from monolayers by the metal chelator ethylenediaminetetraacetic acid were incubated with proteolytic enzymes, and then attachment was quantified by standard cell adhesion assays. The effect of proteinases was found to depend on the presence of Ca2+ in the incubations. Incubation with 100 nM trypsin or chymotrypsin for 1-2 h (37 degrees C) in the absence of Ca2+ reduced cell attachment to vitronectin (Vn), fibrinogen (Fb), laminin, and fibronectin by approximately 80, 80, 40, and 30%, respectively. Viability studies indicated that such treatment with proteinases was not cytotoxic. Inclusion of 0.1 nM CaCl2 in the incubations prevented the loss in attachment to all substrata. In the case of Fb, proteinase treatment in the presence of Ca2+ had an additional effect; it improved cell attachment to this substratum by about 50%. C32 cells have been shown to express the integrin alpha v beta 3 (Vn receptor) which mediates attachment to Vn and Fb in a GRGDS-sensitive manner. Attachment of C32 cells to Vn and Fb prior to proteinase treatment and after proteinase treatment in the presence of Ca2+ was 90% inhibited by the addition of GRGDS peptide to the attachment assays. These results suggest that the adhesion observed both before and after proteinase treatment was mediated by this integrin. Analysis of the Vn receptor from proteinase-treated cells by immunoblotting of cell extracts and by SDS gel electrophoresis of immunoprecipitated receptor revealed no detectable change in either the alpha v or beta 3 subunit that correlated with loss in attachment. Similarly proteinase treatment in the presence of Ca2+ did not produce detectable alterations in the subunits which might correlate with the improved attachment to Fb. Consistent with these results, an enzyme-linked immunoassay to quantify cell surface receptors revealed little difference in the amount of Vn receptor on cells treated with proteinase in the presence or absence of Ca2+. Degradation of the alpha v subunit was demonstrated, however, at proteinase concentrations higher than those required to affect cell attachment. Thus, treatment of cells with serine proteinases can affect integrin-mediated attachment to matrix proteins in a manner moderated by Ca2+, but the alterations in attachment do not appear to be accompanied by detectable proteolytic modification of the integrin.

Amino Acid Sequence↗

Fibronectin-independent attachment of human gingival fibroblasts to interstitial and basement membrane collagens.

We have studied the ability of human gingival fibroblasts (HGF) to attach to different interstitial (types I, II and III) and basement membrane (types IV and V) collagens. HGF cells were plated onto collagen-coated Petri dishes under various conditions and the percentage of cells attaching to the collagen was determined. HGF were found to attach to all the different types of native collagens, but attached poorly to the corresponding denatured collagens. When plated in the presence of 15% fetal bovine serum (FBS) or fibronectin-depleted FBS, similar percentages (approximately 85%) of cells attached to both interstitial and basement membrane collagens, demonstrating an attachment mechanism that is independent of plasma fibronectin. That the attachment in the presence of serum was also independent of cellular fibronectin was shown by the inability of fibronectin antibodies to block attachment to any of the collagen types. HGF were also capable of attaching to all of the collagen types in the complete absence of serum. In previous studies, investigators using cell lines have suggested that cell attachment in the absence of serum is non-physiological. However, the serum-free attachment of HGF to collagen was found to be dependent on cellular protein synthesis indicating that this attachment mechanism has biological significance.

Basement Membrane↗

Role of laminin in the attachment of PAM 212 (epithelial) cells to basement membrane collagen.

Measurements of the attachment of the PAM 212 line of mouse epithelial cells to various collagen substrates show that these cells adhere preferentially to type IV, basement membrane collagen. Neither serum nor fibronectin stimulated the attachment of these cells (unlike fibroblasts) to type IV collagen. Preincubation of the PAM 212 cells with cycloheximide prevented attachment. Thus these cells do not attach by means of a macromolecule present inserum, but instead synthesize an attachment factor. Extracts of the EHS tumor, which produces an extracellular matrix containing basement membrane components, were tested for their ability to promote attachment to cycloheximide-treated PAM 212 cells. Saline extracts of the tumor stimulated the attachment of the PAM 212 cells to type IV collagen in the presence of cycloheximide. Laminin, a high molecular weight glycoprotein constituent of basement membrane, was purified from the salt extract and was found to be the active species at concentrations as low as 1-5 microgram/ml. When laminin was preincubated on plates coated with either type I, II, III, IV, or V collagen and the plates subsequently washed, high levels of attachment were seen only on type IV collagen-coated plates. Affinity purified antibody directed against laminin inhibited the attachment of PAM 212 cells to a type IV collagen substrate. Laminin appears to be a specific attachment protein for epithelial cells since it did not stimulate the attachment of fibroblasts to type I or to type IV collagen substrates. These data suggest that lamin is produced and utilized by these epithelial cells to attach to basement membrane collagen.

Animals↗

Stress causes alteration in attachment of rat hepatocytes to matrix protein substratum.

The effect of different types of stress on the attachment of rat hepatocytes to various matrix protein substrata, such as collagen IV, fibronectin and laminin, was investigated. Study of the kinetics of attachment of adult hepatocytes subjected to heat-shock at 45 degrees C for 30 min showed significantly lower attachment to collagen IV, fibronectin and laminin substrata when compared to untreated controls. The alteration in attachment was observed after heat-treatment for 10 min and the extent of alteration appeared to increase with duration of the heat-treatment, as well as with increase in temperature. Foetal rat hepatocytes, which appeared to attach much more readily than adult rat hepatocytes to these substrata, particularly to laminin, also showed significantly lower attachment to all three substrata after heat-treatment at 45 degrees C for 30 min. This alteration in attachment appeared to be specific for matrix proteins as there was no significant effect on interaction of cells with non-matrix proteins, such as Con A and asialoglycoproteins. While the attachment of adult hepatocytes appeared to attain near control levels in about 4 h, the foetal cells recovered in about 2 h after heat-shock, indicating that the heat-shock effect is reversible and the recovery is faster in foetal hepatocytes. Other stress-causing agents, such as heavy metals, also caused an alteration in attachment of hepatocytes to these matrix proteins. Attachment of adult and foetal hepatocytes to collagen substratum was reduced by 100-microM concentrations of heavy metals in the order Zn > Cd > La > As > Cu for adult cells and La > Zn > As/Cu > Cd for foetal cells. These heavy metals also caused significant reduction in attachment of adult hepatocytes to fibronectin and laminin, although the extent of inhibition was less than that for collagen substrata. However, these heavy metals did not significantly affect the attachment of foetal hepatocytes to laminin substratum indicating that the effect of heavy metals appeared to vary with the nature of the matrix protein substratum. On heat-shock, incorporation of [3H]leucine into cytoskeletal proteins such as cytokeratins CK8 and CK18 was reduced and significant amounts of two new proteins having an average molecular mass of 80 kDa and 90 kDa were found to be tightly associated with cytoskeletal proteins.

Aging↗

Estimating muscle attachment contours by transforming geometrical bone models.

For individualization of a biomechanical model, it is necessary to estimate the muscle attachments of the person to whom it is to be adapted. One of the methods to estimate muscle attachments is to use model transformations to transform a model with known muscle attachments to the bones of a person. We hypothesize that the location and shape of muscle attachment sites correlate with the shape of the bones they are attached to. If this hypothesis holds, it is possible to predict the location of muscle attachments when the shape of the bones is known. To validate this hypothesis, geometric models of three sets of shoulder bones were built. These models consist of 3-D surface models of the scapula, clavicle, and humerus, with the muscle attachment contours connected to them. By means of geometric transformations, the models were transformed, so the muscle attachments of the different data sets could be compared. Using these techniques, 50 per cent of the muscle attachment contours could be predicted with high accuracy. The muscle attachment contours that could not be predicted were all influenced by measurement errors. For 30 per cent of the muscle attachment contours, it was not possible to distinguish the interindividual differences from the inaccuracies of the method used. From this study, we concluded that most muscle attachment contours can be predicted by means of geometric models of the bones.

Algorithms↗

Mechanism of initial attachment of corneal epithelial cells to polymeric surfaces.

The initial attachment of cultured bovine corneal epithelial cells and stromal fibroblasts to two oxygen-containing synthetic polymers was studied. Cultured epithelial cells and stromal fibroblasts were seeded onto two oxygen-containing surfaces: 'tissue culture' polystyrene (TCPS) and a polymer film deposited by RF plasma deposition using a methylmethacrylate monomer (MMA/FEP). To establish the mechanism of cell attachment, the effect of the selective removal of the vitronectin and fibronectin from the serum used in the culture medium was tested. The attachment of cultured epithelial cells during the first 90 min of culture was reduced by 40% (TCPS)-80% (MMA/FEP) as a result of removing vitronectin from the medium. Attachment of these cells to TCPS was reduced by 85-95% when the serum was depleted of both fibronectin and vitronectin. However, depletion of fibronectin reduced cell attachment to TCPS by 20%, whilst on MMA/FEP cell attachment was equivalent, or higher, than that for intact serum. The attachment of cultured corneal stromal fibroblasts was similarly dependent on vitronectin but less dependent on fibronectin. Therefore, for the attachment of both cultured epithelial cells and fibroblasts to oxygen-containing surfaces in the presence of serum, there is a high requirement for serum vitronectin but a lesser requirement for fibronectin. The effects of the establishment of corneal epithelial cells in culture and the site of origin of the cells, were determined. Primary isolates of epithelial cells isolated from the limbal, central or peripheral regions of the cornea were less dependent on vitronectin for initial attachment to TCPS than were these cells after several passages in culture. Furthermore, the primary isolates were dramatically less responsive to vitronectin than the cultured cells. These results indicate that the mechanism of attachment of corneal epithelial cells to TCPS varies with the culture experience of the cells. Cells that are culture neophytes can employe endogenous mechanisms for the initial attachment to TCPS, whereas cells established in culture are dependent on exogenous vitronectin in order to attach.

Animals↗