CD<Subscript>4</Subscript><Superscript>+</Superscript>CD<Subscript>25</Subscript><Superscript>+</Superscript> Regulatory T Cells Decreased the Antitumor Activity of Cytokine-Induced Killer (CIK) Cells of Lung Cancer Patients

CD₄ ⁺CD₂₅ ⁺ regulatory T cells (Tregs) have been shown to inhibit cytotoxic lymphocytes-mediated immune responses. Cytokine-induced killer (CIK) cells exert high impact on adoptive immunotherapeutic approaches. Therefore, the purpose of this report was to determine the effect of Tregs on CIK cell growth and CIK-induced cytotoxicity for inhibition of tumor growth in vivo as well as in vitro. After depletion of CD₄ ⁺CD₂₅ ⁺ cells before culture, the proliferation and cytotoxicity of CIK cells, which indicated in bromodeoxyuridine (BrdU) and lactic dehydrogenase (LDH) assays, were significantly increased. Depletion of CD₄ ⁺CD₂₅ ⁺ cells preculture also enhanced the suppression effect on the lung cancer cells inoculated in experimental animals. Blockage of glucocorticoid-induced tumor necrosis factor receptor (GITR) and transforming growth factor β1 (TGF-β1) by antibodies partially abrogated the suppressive effect of CD₄ ⁺CD₂₅ ⁺ cells on CIK. These results indicated that Tregs could inhibit the antitumor activity of CIK cells. The molecules TGF-β and GITR may contribute to the suppressive function of CD₄ ⁺CD₂₅ ⁺ cells.     

白血病抑制因子(LIF)与bFGF协同促进小鼠外胚间充质干细胞(EMSCs)体外自我维持

白血病抑制因子（leukemia inhibitor factor，LIF）可以抑制小鼠胚胎干细胞分化，维持其自我更新，因而用于该干细胞的体外扩增。由于不同的胚胎或成体干细胞分化特性相差很大，因此，LIF可能对不同的干细胞有不同的作用。对新鲜分离的小鼠外胚间充质细胞（ectomesenchymal cells，EMCs）在有或无LIF的培养条件下，观察了细胞生长的特性，表型变化等，并通过检测其中外胚间充质干细胞（ectomesenchymal stem cells，EMSCs）的水平，探讨UF与EMSCs的关系。结果表明：（1）LIF的受体gp130表达于未分化与早期分化的EMSCs表面，提示LIF对于EMSCs具有潜在的调节作用；（2）LIF促进小鼠EMSCs的自我维持，bFGF则对此具有协同作用。因此，UF与bFGF联合对体外培养和扩增小鼠外胚间充质干细胞，以及对其深入研究和应用具有重要意义。     

Mesenchymal Stem Cells Ameliorate Podocyte Injury and Proteinuria in a Type 1 Diabetic Nephropathy Rat Model

Mesenchymal stem cells (MSC) attenuate albuminuria and preserve normal renal histology in diabetic mice. However, the effects of MSC on glomerular podocyte injury remain uncertain. The aim of this study was to evaluate the effects of MSC on podocyte injury in streptozotocin (STZ)-induced diabetic rats. Thirty days after diabetes induction by STZ injection (65 mg/kg, intraperitoneally) in Sprague-Dawley rats, the diabetic rats received medium or 2 × 10⁶ enhanced green fluorescent protein-labeled MSC via the renal artery. In vivo tracking of MSC was followed by immunofluorescence analysis. Diabetes-related physical and biochemical parameters were measured on day 60 after the MSC infusion. The expression of podocyte markers (nephrin and podocin), podocyte survival factors (VEGF and BMP-7), and the ultrastructural pathology of podocytes were also assessed. MSC were only detected in the glomeruli from the left kidney receiving MSC infusion. Compared with medium-treated diabetic rats, rats treated with MSC showed a suppressed increase in kidney weight, kidney to body weight index, creatinine clearance rate, and urinary albumin to creatinine ratio; however, the treatment had no effect on blood glucose or body weight levels. Furthermore, the MSC treatment reduced the loss of podocytes, effacement of foot processes, widening of foot processes, thickening of glomerular basal membrane (GBM), and loss of glomerular nephrin and podocin. Most important, MSC-injected kidneys expressed higher levels of BMP-7 but not of VEGF. Our results clearly demonstrated that intra-arterial administration of MSC prevented the development of albuminuria as well as any damage to or loss of podocytes, though there was no improvement in blood sugar levels. The protective effects of MSC may be mediated in part by increasing BMP-7 secretion.     

Distribution of <Superscript>3</Superscript>H-Dopamine and <Superscript>3</Superscript>H-DAGO Binding Sites in the Central Part of Rat Sinoatrial Node

Distribution of ³H-dopamine and ³H-DAGO binding sites was studied by autoradiography on semithin sections of total preparations of rat sinoatrial node. The relative density of ³H-dopamine and ³H-DAGO binding sites in the functional nucleus of the sinoatrial node was minimum and increased in the cranial and caudal directions. The level of ³H-dopamine binding in the perinodal atrial myocardium was appreciably lower (22±6%), while binding of ³H-DAGO was similar (76±16%) to that in the periarterial zone of the sinoatrial node. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 8, pp. 210–214, August, 2005     

Single Audiogenic Seizures Induce Increases in Calcineurin and Ca<Superscript>2+</Superscript>-Calmodulin-Dependent Protein Kinase II in the Rat Brain

Ca²⁺-calmodulin-dependent protein kinase II (CaMKII) and protein phosphatase 2B (calcineurin) play critical roles in the formation of nerve cell responses to incoming Ca²⁺ signals. The studies report here addressed how single seizures might affect the functioning of these enzymes. Sounds (80 dB, 12–15 kHz) induced single convulsions in male Krushinskii–Molodkina rats, which have an inherited predisposition to audiogenic seizures. Biochemical investigations were performed two days after seizures. Immunoblotting studies with specific monoclonal antibodies demonstrated increases in the level of the neurospecific α subunit of CaMKII in the sensorimotor cortex and hippocampus of the rats of the experimental group, as compared with controls. The hippocampus of rats which had had seizures also showed increases in the catalytic subunit of calcineurin. CaMKII activity in the hippocampus and cortex of postseizure rats increased, though that of the Ca²⁺-calmodulin-independent functional form of the enzyme did not change. It is suggested that the long-term changes seen here may represent an adaptive mechanism induced by convulsive activity and directed to increasing the threshold of neuron excitability in the brain.     

Subcellular Distribution and Mitogenic Effect of Basic Fibroblast Growth Factor in Mesenchymal Uncommitted Stem Cells

Uncommitted mesenchymal stem cells (MSC), upon commitment and differentiation give rise to several mature mesenchymal lineages. Although the involvement of specific growth factors, including FGF2, in the development of committed MSC is known, the effect of FGF2 on uncommitted progenitors remains unclear. We have analyzed on a comparative basis, the subcellular distribution and mitogenic effect of FGF2 in committed and uncommitted MSC prepared from human bone marrow. Indirect immunofluorescence studies showed strong nuclear FGF2 staining in both progenitors; however, cytoplasmic staining was only detected in committed cells. Western blot analysis revealed the presence of 22.5 and 21-22 kDa forms of FGF2 in the nucleus of both progenitors; however, their relative content was higher in uncommitted than in committed cells. Exogenous FGF2 stimulated proliferation and sustained quiescence in committed and uncommitted cells, respectively. These results show that both type of progenitors, apart from morphological and proliferative differences, display specific patterns of response to FGF2.     

Flow Cytometric Identification of CD93 Expression on Naive T Lymphocytes (CD4<Superscript>+</Superscript>CD45RA<Superscript>+</Superscript> Cells) in Human Neonatal Umbilical Cord Blood

Human CD93 has a molecular weight of about 100 kDa and is selectively expressed by myeloid cell lineages in peripheral blood (PB) mononuclear cells. Although CD93 was initially identified as a receptor for complement component 1, subcomponent q phagocytosis (C1qRp) involved in the C1q-mediated enhancement of the phagocytosis of various antigens, several recent studies have reported that CD93 is not a receptor for the C1q-mediated enhancement of phagocytosis. The expression patterns of CD93 have been previously investigated in PB mononuclear cells (lymphocytes, monocytes, and granulocytes) from adult PB and neonatal umbilical cord blood (UCB), and the expression of CD93 was not found on lymphocytes from either normal adult PB or neonatal UCB. However, the detection of CD93 expression in neonatal UCB using CD93 monoclonal antibodies (mAbs) that recognize different antigenic epitopes remains poorly understood. In this study, we examined the expression of CD93 on lymphocytes, monocytes, and granulocytes from neonatal UCB using four different types of CD93 mAb detection probes, mNI-11, R139, R3, and X-2, using flow cytometric and western blot analyses. We found that CD93, as defined using all four mAbs, was expressed on monocytes and granulocytes in PB mononuclear cells from adult PB and neonatal UCB. On the other hand, we observed for the first time that the expression of CD93 on lymphocytes in neonatal UCB can only be detected using the mNI-11 mAb, established in our laboratory, and not with commercially available CD93 mAbs (R139, R3, and X-2). However, CD93 expression on lymphocytes from normal adults was not detected using any of the four CD93 mAbs. Two-color flow cytometric analyses showed that the CD93 recognized by mNI-11 mAb was expressed on CD3⁺ T lymphocytes (mainly CD4⁺ helper T lymphocytes), but not on CD19⁺ B lymphocytes or on CD8⁺ suppressor/cytotoxic T lymphocytes from neonatal UCB. In addition, CD93 was expressed on CD45RA⁺ (naive antigen) lymphocytes from neonatal UCB, but not on CD45RO⁺ (memory antigen) lymphocytes from neonatal UCB or on CD45RA⁺ and CD45RO⁺ lymphocytes from normal adult PB. Three-color flow cytometric analysis showed that CD93 was co-expressed on naive T lymphocytes (CD4⁺CD45RA⁺) from neonatal UCB. In a western blot analysis, the CD93 mAb (mNI-11) immunoprecipitated at a molecular weight of 98 kDa, identified as a CD93 molecule, in the CD4⁺CD45RA⁺ cells from neonatal UCB but not from adult PB, similar to the results in the human monocyte-like cell line U937 (human CD93-positive cells). Taken together, these results provide the first direct evidence of a novel/naive cell population (CD4⁺CD45RA⁺CD93⁺) in neonatal UCB that may have an important role in cell biology, transplantation, and immature/mature immune responses.     

Expression of p21<Superscript>cip1</Superscript>, p27<Superscript>kip1</Superscript>, and p16<Superscript>INk4a</Superscript> Cyclin-Dependent Kinase Inhibitors in Papillary Thyroid Carcinoma: Correlation with Clinicopathological Factors

In a variety of human malignancies, aberrant expression of proteins involved in the control of cell-cycle progression has been reported. In this study, p21^cip1, p27^kip1, and p16^INk4a cyclin-dependent kinase inhibitors were analyzed to evaluate their usefulness in clinical management of papillary thyroid carcinoma (PTC). Archived material derived from 46 cases of PTC was analyzed immunohistochemically. Protein expression was ascertained on tissue microarrays, and results were correlated with clinicopathological features of the patients. Positive immunostaining was observed in 14 (30,4%) p21^cip1, 26 (56,5%) p27^kip1, and 14 (30,4%) p16^INk4a cases. No significant correlation between p21^cip1 or p27^kip1 and clinical factors was found. In contrast, p16^INk4a expression showed a significant correlation with initial extension of the disease. Therefore, 45.8% of patients with loco-regional extension were p16^INk4a positive, whereas overexpression was only seen in 15.7% of cases with intrathyroid disease (p < 0.05). Moreover, all patients with simultaneous p16^INk4a positivity and lack of p27^kip1 staining (four patients) presented lymph node metastases. In contrast, only 12 (28.5%) of the remaining patients showed lymph node tumor involvement. In conclusion, p16^INk4a expression suggests extrathyroid neck extension of PTC. This effect is enhanced when p27^kip1 is negative. We think that their analysis by immunohistochemistry could be useful in the management of patients with PTC.     

Accumulation of CD5<Superscript>+</Superscript>CD19<Superscript>+</Superscript> B lymphocytes expressing PD-1 and PD-1L in hypertrophied pharyngeal tonsils

Programmed death-1 (PD-1) is one of the most important inhibitory co-receptors expressed predominantly on activated T and B lymphocytes whose expression could be sustained by permanent antigenic stimulation accompanying chronic or recurrent tonsillitis. The expression of PD-1 and PD-1L was analyzed using flow cytometry on hypertrophied tonsils collected from 57 children. We observed high expression of PD-1 and PD-1L on certain lymphocytes subpopulations of hypertrophied tonsils; among T cells, the expression of PD-1 on protein level was higher on CD4⁺ cells (70.3 %) than on CD8⁺ cells (35 %). Interestingly, a limited expression of PD-1 was observed on CD19⁺ B lymphocytes (6.5 %), while CD5⁺CD19⁺ B cells overexpressed PD-1 (52.5 %). Moreover, the expression of PD-1L was also higher on CD5⁺CD19⁺ B cells (16.5 %) than on CD19⁺ B cells (3.5 %) and on CD4⁺ T cells (20 %) than on CD8⁺ T cells (10 %). PD-1 and PD-1L expressions correlated only on CD5⁺CD19⁺ cells. In conclusion, high expression of PD-1 and PD-1L on T and B cells could represent hallmark of immune system adaptation to chronic antigenic exposition in patients with tonsillitis.     

Clinical Impact of <Emphasis Type="Italic">p27</Emphasis><Superscript><Emphasis Type="Italic">Kip1</Emphasis></Superscript> and CaSR Expression on Primary Hyperparathyroidism

We aimed to investigate the expressions of p27 kinase inhibitory protein 1 (p27^Kip1) and calcium sensing receptor (CaSR) in adenomas and normal parathyroid tissue and to evaluate the relationship of these molecules with clinical and biochemical parameters in primary hyperparathyroidism (PHPT). Fifty-one patients with histopathologically confirmed parathyroid adenomas and 20 patients with normal parathyroid glands (which were removed incidentally during thyroid resection) were included. Immunohistochemical stainings of CaSR and p27^Kip1 were performed in surgical specimens. Clinical features, biochemical parameters, and BMD measurements of patients with PHPT were evaluated retrospectively. Expressions of p27^Kip1 and CaSR were decreased in parathyroid adenomas, compared to normal glands (p <?0.05). High intensity of CaSR staining (3+) was more frequent in normal parathyroid tissue (75%) than adenomas (12%) (p <?0.01). Hypertension was not observed in patients with high staining intensity of CaSR (p =?0.032). There was a negative association between CaSR expression and body mass index (BMI) (p =?0.027, r =???0.313). There was no significant relationship between p27^Kip1 and CaSR expressions, serum calcium, plasma parathormone, 25-hydroxy vitamin D levels, and bone density (p >?0.05). The expressions of p27^Kip1 and CaSR were decreased in PHPT patients. This reduction may play an important role in the pathogenesis of PHPT. However, neither p27^Kip1 nor CaSR expression was found to be useful in predicting prognosis or severity of disease.     

CD27<Superscript>+</Superscript>TIM-1<Superscript>+</Superscript> memory B cells promoted the development of Foxp3<Superscript>+</Superscript> Tregs and were associated with better survival in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a rapid onset life-threatening condition involving uncontrolled propagation of inflammatory responses. Here, we observed that ARDS patients that survived presented significantly higher frequencies of TIM-1⁺ B cells, especially the CD27⁺TIM-1⁺ B cells, than the ARDS patients who succumbed to the condition. We then found that using BCR/CD40 antigen-dependent stimulation or Staphylococcus aureus Cowan (SAC) antigen-independent stimulation, TIM-1⁺ B cells presented significantly higher IL-10 secretion and/or TGF-β1 secretion, with SAC stimulation being more effective. CD4⁺ T cells that incubated with TIM-1⁺ B cells presented significantly elevated IL-10 secretion, TGF-β1 secretion, and Foxp3 expression, than CD4⁺ T cells that incubated with TIM-1^? B cells, suggesting TIM-1⁺ B cells promoted the in vitro development of Foxp3⁺ Treg cells. Interestingly, this TIM-1⁺ B cell-mediated promotion of Foxp3 expression was mostly dependent on TGF-β1 but not IL-10, since neutralization of TGF-β1, but not IL-10, resulted in the suppression of Foxp3 expression. We further showed that in TIM-1⁺ B cells, the CD27⁺ classical memory B cell subset demonstrated more regulatory potency than the CD27^? subset. Together, our results suggested that the TIM-1⁺ B cells, especially those that expressed CD27, could promote Foxp3 expression. Their clinical efficacy in treating ARDS should be examined in in vivo experiments.     

A Distinct Role of CD4<Superscript>+</Superscript> Th17- and Th17-Stimulated CD8<Superscript>+</Superscript> CTL in the Pathogenesis of Type 1 Diabetes and Experimental Autoimmune Encephalomyelitis

Both CD4(+) Th17-cells and CD8(+) cytotoxic T lymphocytes (CTLs) are involved in type 1 diabetes and experimental autoimmune encephalomyelitis (EAE). However, their relationship in pathogenesis of these autoimmune diseases is still elusive. We generated ovalbumin (OVA)- or myelin oligodendrocyte glycoprotein (MOG)-specific Th17 cells expressing RORγt and IL-17 by in vitro co-culturing OVA-pulsed and MOG(35-55) peptide-pulsed dendritic cells (DC(OVA) and DC(MOG)) with CD4(+) T cells derived from transgenic OTII and MOG-T cell receptor mice, respectively. We found that these Th17 cells when transferred into C57BL/6 mice stimulated OVA- and MOG-specific CTL responses, respectively. To assess the above question, we adoptively transferred OVA-specific Th17 cells into transgenic rat insulin promoter (RIP)-mOVA mice or RIP-mOVA mice treated with anti-CD8 antibody to deplete Th17-stimulated CD8(+) T cells. We demonstrated that OVA-specific Th17-stimulated CTLs, but not Th17 cells themselves, induced diabetes in RIP-mOVA. We also transferred MOG-specific Th17 cells into C57BL/6 mice and H-2K(b-/-) mice lacking of the ability to generate Th17-stimulated CTLs. We further found that MOG-specific Th17 cells, but not Th17-activated CTLs induced EAE in C57BL/6 mice. Taken together, our data indicate a distinct role of Th17 cells and Th17-stimulated CTLs in the pathogenesis of TID and EAE, which may have great impact on the overall understanding of Th17 cells in the pathogenesis of autoimmune diseases.     

<Superscript>1</Superscript>H nuclear magnetic resonance (NMR)-based serum metabolomics of human gallbladder inflammation

Objective and design

We present in this article ¹H nuclear magnetic resonance (NMR)-based metabolic approach to screen the serum metabolic alterations in human gallbladder inflammation with chronic cholecystitis (CC).

Material/methods

Total of 71 human serum samples was divided into two groups, (n = 41, CC) and (n = 30 control). ¹H NMR metabolic profiling was carried out for investigation of metabolic alterations. Multivariate statistical analysis was applied for pattern recognition and identification of metabolites playing crucial role in gallbladder inflammation. Receiver operating curve (ROC) and pathway analysis on NMR data were also carried out to validate the findings.

Results

Serum metabolites such as glutamine, low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), alanine, branch chained amino acids (BCAA), histidine and tyrosine were found to be depleted whereas formate, lactate, 1,2-propanediol were found to be elevated in CC. Metabolic pathways associated with metabolite alteration have also been reported.

Conclusions

NMR has been established for disease diagnosis along with identification of metabolic pattern recognition in biofluids. Gallstones cause inflammation of the gallbladder in the form of CC. Inflammation plays a major role in causation of gall bladder cancer and leads the way to malignancy. Metabolic analysis of CC may lead to early diagnosis of disease and its progression to gallbladder cancer.

     

The Angiogenic Peptide Vascular Endothelial Growth Factor–Basic Fibroblast Growth Factor Signaling is Up‐Regulated in a Rat Pressure Ulcer Model

The purpose of this study is to investigate the mRNA and protein expression levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in pressure ulcers, and to elucidate the molecular mechanism by which VEGF and bFGF are involved in pressure ulcer formation. A rat model of ischemia‐reperfusion pressure ulcer was established by magnetic disk circulating compression method. Real‐time fluorescence quantitative PCR and Western blot assays were conducted to detect the mRNA and protein expression of VEGF and bFGF in the tissues of rat I‐, II‐, and III‐degree pressure ulcers, the surrounding tissues, and normal skin. Our study confirmed that the mRNA and protein expression levels of VEGF and bFGF in the tissues of rat I‐degree pressure ulcer were significantly higher than that in the II‐ and III‐degree pressure ulcer tissues (P < 0.05). The expression of VEGF and bFGF in the tissues surrounding I‐ and II‐degree pressure ulcers were higher than the rats with normal skin. The expression of VEGF and bFGF in the tissues of rat III‐degree pressure ulcer was lower than that in the surrounding tissues and normal skin (P < 0.05). There was a significant positive correlation between change in the VEGF and bFGF. The results showed that with an increase in the degree of pressure ulcers, the expression of VEGF and bFGF in pressure ulcers tissue are decreased. This leads to a reduction in angiogenesis and may be a crucial factor in the formation of pressure ulcers. Anat Rec, 2013. © 2013 Wiley Periodicals, Inc.     

Spontaneous Proliferation and Type 2 Cytokine Secretion by CD4<Superscript>+</Superscript>T Cells in Patients with Metastatic Melanoma Vaccinated with Antigen-Pulsed Dendritic Cells

We observed the induction of spontaneous, i.e., without adding exogenous antigen, in vitro proliferation of PBMCs from patients with stage IV melanoma who underwent repeated vaccinations with antigen-loaded dendritic cells (DCs) derived from CD34⁺ hematopoietic progenitors (CD34-DCs). Proliferating cells are CD4⁺T cells. Their proliferation is dependent on (1) CD11c⁺ myeloid DCs, since their depletion from PBMCs abolishes it; and (2) IL-2, as it can be blocked by neutralizing anti-IL-2 antibodies. Spontaneous proliferation is associated to the secretion of type 2 cytokines. To analyze the frequency of spontaneous proliferation induction in the cohort of 18 vaccinated patients, an index of spontaneous proliferation was defined as a ratio of PBMCs proliferation from post- vs pre-DC vaccination blood samples. Ten out of sixteen analyzed patients showed an index > 2. The index of spontaneous proliferation correlates with antigen-specific PBMC proliferation to the vaccine antigen KLH. Furthermore, both spontaneous- and antigen-specific proliferation in PBMC cultures are dependent on blood myeloid DCs.     

Role of Stromal and Thy 1,2<Superscript>+</Superscript> Cells in the Mechanisms of Action of Immobilized Granulocyte Colony-Stimulating Factor during Cytostatic-Induced Myelosuppression

The effects of immobilized granulocyte colony-stimulating factor (mediated by cells of the hemopoiesis-inducing microenvironment) on hemopoietic precursors of various classes were studied on the model of cytostatic-induced myelosuppression (administration of cyclophosphamide). The action of this preparation was compared with that of the standard preparation of granulocyte colony-stimulating factor. Thy 1,2⁺ cells potentiated the effects of immobilized and standard granulocyte colony-stimulating factors on granulocyte-erythroid-macrophagemegakaryocyte precursors. Stromal cells were shown to potentiate the influence of these agents on granulocyte precursors. Induction of proliferation of precursor cells by the immobilized factor mediated by cells of the hemopoiesis-inducing microenvironment persisted for a longer period compared to that induced by the standard product.     

Distribution of Acidic and Basic Fibroblast Growth Factors (FGF) in the Foetal Rat Eye: Implications for Lens Development

Abstract

Previously we reported that, in vitro, lens cells proliferate, migrate or differentiate in response to low, medium and high concentrations of FGF respectively. To examine further the role of FGF in lens development we used immunohistochemistry to study the distribution of aFGF and bFGF in the eye of the 20 day rat foetus. Strong aFGF-like reactivity was localised in a band of cells near the lens equator which included the germinative zone where most cell proliferation occurs and the transitional zone where epithelial cells differentiate into fibres. The closely apposed inner epithelial layer of the ciliary and iridial retina also reacted strongly. Reactivity for aFGF was also found in the epidermis and in the corneal and conjunctival epithelia. In the neural retina, reactivity was found in the nerve fibre layer and in isolated cells of the inner plexiform layer. bFGF-like reactivity was found in the retinal ganglion cell layer, extra-ocular muscles and associated with endothelial cells of the hyaloid, lenticular and choroid vasculatures. Pre-digestion of sections with hyaluronidase caused loss of cell-associated reactivity but revealed strong bFGF-like reactivity in ocular basement membranes, in particular, the lens capsule. The sensitivity of this capsular bFGF localisation to heparinase indicates that bFGF in the extracellular matrix is complexed with heparan sulphate proteoglycans. The results of this study are consistent with the hypothesis that FGF plays an important role in lens development via both autocrine and paracrine mechanisms.