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K D Cooper

Publications and source records attributed to K D Cooper.

At least 73 records · Page 4Linked to original sources
PubMed1995

The ICAM-3/LFA-1 interaction is critical for epidermal Langerhans cell alloantigen presentation to CD4+ T cells.

Intercellular adhesion molecule (ICAM)-3 is a recently described member of the immunoglobulin superfamily and, as such, is closely related to ICAM-1 and ICAM-2. All three ICAMS are cognate for the counter-receptor lymphocyte function associated antigen-1 (LFA-1, CD11a/CD18). Unlike ICAM-1 and ICAM-2, ICAM-3 is constitutively expressed at high levels on resting leucocytes. We investigated the expression and function of ICAM-3 in normal skin (n = 5), as well as its expression in psoriasis (n = 4), atopic eczema (n = 4), allergic (rhus) contact dermatitis (n = 3), and cutaneous T-cell lymphoma (CTCL, n = 2). Five-micrometre cryostat sections of skin were stained using monoclonal antibodies to ICAM-3 and a well characterized immunoperoxidase technique. In normal skin, ICAM-3 was expressed by all cutaneous leucocytes but most striking was the strong expression of ICAM-3 by Langerhans cells within both epidermis and dermis. This observation was confirmed by double-labelling with CD1a and negative staining with an IgG1 isotype control. In psoriasis, atopic eczema, allergic contact dermatitis, and CTCL, ICAM-3 was co-expressed on all CD1a+ cells, although, in psoriasis, the intensity of ICAM-3 expression was reduced. Functional blocking experiments were performed to determine whether the observed ICAM-3 expression on Langerhans cells was functionally important in antigen presentation. CD4+ T cells were prepared from peripheral blood and 10(5) CD4+ T cells combined with 10(5) epidermal cells harvested from keratome biopsies of normal skin of an individual allogeneic to the T-cell donor. Addition of 50 micrograms anti-ICAM-3 to the co-culture resulted in a consistent (50%) reduction in degree of alloantigen presentation by Langerhans cells to T cells. Inhibition was 77% of that produced by the addition of anti-LFA-1. These data indicate that ICAM-3 is constitutively expressed by Langerhans cells and is a major ligand for LFA-1 on CD4+ T cells during their response to Langerhans cells. Because fresh Langerhans cells constitutively express little ICAM-1, whereas ICAM-3 is constitutively expressed at high levels, it would appear that ICAM-3 is the dominant functional ICAM on in situ Langerhans cells in the normal epidermis.

Antigen Presentation↗
PubMed1995

Kinetics and regulation of human keratinocyte stem cell growth in short-term primary ex vivo culture. Cooperative growth factors from psoriatic lesional T lymphocytes stimulate proliferation among psoriatic uninvolved, but not normal, stem keratinocytes.

Flow cytometric analysis of primary ex vivo keratinocyte cultures demonstrated that stem cells, (beta 1 integrin+, keratin 1/keratin 10 [K1/K10-], proliferating cell nuclear antigen [PCNA-] [Bata-Csorgo, Zs., C. Hammerberg, J. J. Voorhees, and K. D. Cooper. 1993. J. Exp. Med. 178:1271-1281]) establish such cultures. This methodology also enabled the quantitation of synchronized recruitment of these cells from G0 into G1 of the cell cycle (PCNA expression), which preceded bright beta 1 integrin expression. (beta 1 integrinbright expression has been shown to be a characteristic feature of keratinocyte stem cells in culture (Jones, P. H., and F. M. Watt. 1993. Cell. 73:713-724). Using the above assay, we determined whether lesional T lymphocytes in psoriasis could be directly responsible for the induction of the stem cell hyperproliferation that is characteristic of this disease. Indeed, CD4+ T lymphocytes, cloned from lesional psoriatic skin and stimulated by immobilized anti-CD3 plus fibronectin, promoted psoriatic uninvolved keratinocyte stem cell proliferation via soluble factors. This induction appeared to be through accelerated recruitment of stem cells from their quiescent state (G0) into cell cycle. By contrast, normal keratinocyte stem cells exhibited no such growth stimulation. Supernatants exhibiting growth induction all contained high levels of GM-CSF and gamma-IFN, low IL-3 and TNF-alpha, and variable IL-4. Only anti-gamma-IFN antibody was able to neutralize growth stimulatory activity of the supernatants on psoriatic uninvolved keratinocyte stem cells. However, because recombinant gamma-IFN alone inhibited growth in this assay, these data suggest that, in psoriasis, gamma-IFN acts cooperatively with other growth factors in the immune induction of cell cycle progression by the normally quiescent stem cell keratinocytes.

CD4 Antigens↗
PubMed1995

A pilot study of the effect of oral 8-methoxypsoralen and intraarticular ultraviolet light on rheumatoid synovitis.

OBJECTIVE: To determine the feasibility and safety of combining oral 8-methoxypsoralen (8-MOP) and intraarticular ultraviolet A band light (UVA) to treat rheumatoid synovitis, and to demonstrate a favorable biological effect. METHODS: Six patients with rheumatoid arthritis (RA) and clinically evident knee synovitis were given a single oral dose of 8-MOP (0.6 mg/kg) followed by arthroscopy with a UVA laser equipped small arthroscope. Nine tissue samples treated with UVA doses ranging from 4 to 52 J/cm2 were examined by light microscopy and by immunohistochemistry for vascular cell adhesion molecule 1 (VACM-1), intracellular adhesion molecule 1 (ICAM-1), E-selectin and HLA-DR expression. RESULTS: No reduction in inflammation was evident on light microscopy, nor was there any evidence of tissue injury on gross inspection or light microscopy. At 28 and 52 J/cm2, VCAM-1, ICAM-1 and E-selectin staining were reduced in the posttreatment synovial biopsies. No local or systemic complications were observed by Day 30 in any patient. CONCLUSION: This treatment modality appears to be feasible and safe and may potentially be useful in the treatment of the synovitis associated with RA.

Adult↗
PubMed1995

Woringer-Kolopp disease (localized pagetoid reticulosis) or unilesional mycosis fungoides? An analysis of eight cases with benign disease.

BACKGROUND: The controversial nosology of Woringer-Kolopp disease (localized pagetoid reticulosis, unilesional mycosis fungoides) is being clarified by the systematic immunophenotypic and immunogenetic examination of infiltrating lesional T lymphocytes. The clinical course and immunohistochemical characteristics of eight cases of Woringer-Kolopp disease are described. OBSERVATIONS: Lesions measured 0.8 x 0.5 to 16.0 x 15.0 cm. Histologically, all cases resembled mycosis fungoides-type cutaneous T-cell lymphoma and phenotypic analysis supported their designation as an epidermotropic T-cell process. Phenotypic aberrancy was not noted on immunohistochemical analysis of paraffin-embedded tissue. Three of four patients with available fresh-frozen tissue specimens demonstrated reduced or absent expression of CD7 (Leu-9) and/or Leu-8, while loss of the pan-T-cell markers CD2, CD3, and CD5 was not observed. Only in half these patients was a lesional predominance of CD4+ T-cells revealed. Germline DNA was detected in a lesional skin specimen obtained from one patient tested for T-cell receptor gene rearrangements. After treatment, the observation of disease-free periods ranging from 18 months to 17 years (mean, 5.9 years) reinforces the view that Woringer-Kolopp disease is a focal pathologic event with a favorable prognosis. No patient experienced a local recurrence or distant spread of the disease. CONCLUSION: This and previous studies suggest that Woringer-Kolopp disease is a unique, benign unilesional T-cell lymphoproliferative process with certain histologic and phenotypic similarities to both early epidemotropic mycosis fungoides-type cutaneous T-cell lymphoma and other T-cell lymphoproliferations.

Adult↗
PubMed1994

Active induction of unresponsiveness (tolerance) to DNFB by in vivo ultraviolet-exposed epidermal cells is dependent upon infiltrating class II MHC+ CD11bbright monocytic/macrophagic cells.

Contact sensitizers, tumor Ags, and microbial pathogens presented through UV-exposed skin result in T cell-mediated immune tolerance (inhibition of acquisition of responsiveness) to these normally potent immunogens. The APC in UV-exposed skin that delivers the signals inducing tolerance remains highly controversial and is the subject of this study. Application of the contact sensitizer, 2,4-dinitro-1-fluorobenzene (DNFB), to C3H/HeN mice immediately after a single dose of 72 mJ/cm2 UVB (138 mJ/cm2 total UVB) resulted in unresponsiveness to an initial DNFB ear challenge, but failed to block the development of responsiveness after a second sensitization on previously unexposed skin (no tolerance). A state of tolerance could only be achieved if a delay of 72 h was allowed to elapse between the UV exposure and the initial sensitization. Epidermal cell suspensions (EC) were prepared from the skin of normal controls and from skin exposed to the same UV dose 3 days before (UV-EC). Three days after in vivo UV exposure, Langerhans cells (CD11blow Ia+) were depleted, and CD11bbright Ia+ macrophages had appeared in the epidermis along with GR-1+ neutrophils. Intracutaneous injection of 2,4 dinitrobenzenesulfonic acid (DNBSO3)-haptenated UV-EC, but not normal controls, resulted in the induction of locally inducible Ag-specific tolerance to DNFB, indicating the presence and dominance of tolerogenic signal within in vivo-irradiated epidermis. Removal of CD11b+ and class II MHC+ cells within UV-EC showed that a CD11b+ class II MHC+ population was indeed critical for tolerance induction. In addition, tolerance induction by UV-EC was not a result of surviving, UV-exposed Langerhans cells, because haptenated 3-day cultured EC from epidermis removed 5 h after UV exposure (before leukocytic infiltration) failed to induce a tolerogenic state. In conclusion, the ability of UV-exposed skin to induce peripheral adult tolerance to a normally potent immunogen is critically dependent on inflammatory class II MHC+, CD11bbright monocytic/macrophagic cells that infiltrate UV-irradiated skin at the same time the ability to tolerize is acquired.

Animals↗
PubMed1994

CD11b+ macrophages that infiltrate human epidermis after in vivo ultraviolet exposure potently produce IL-10 and represent the major secretory source of epidermal IL-10 protein.

Because activated human macrophages can be potent sources of IL-10, and because immunosuppressive tolerance-inducing macrophages populate the skin after UV exposure, we determined whether IL-10 is induced after UV exposure of human skin and whether it is related to the immigrating macrophages. Keratomes were obtained from control skin or from skin obtained 72 h after a single exposure to four minimal erythemal doses of UVB. Quantitative reverse-transcriptase PCR on total RNA extracted immediately from skin keratomes showed that IL-10 mRNA was elevated in UV-exposed skin. Epidermal cell suspensions from non-UV-exposed keratomes (C-EC) and UV-exposed keratomes (UV-EC) were fractionated by sequential immunobead selection. IL-10 mRNA was reproducibly 200- to 400-fold higher in CD11b+ UV-EC (macrophages) relative to CD11b- UV-EC (keratinocytes). IL-10 mRNA was not detected in C-EC that contained the CD1a+ population (Langerhans cells) nor in CD1a- C-EC keratinocytes from normal skin. As determined by ELISA, CD11b+ UV-EC IL-10 cell-associated protein was fivefold higher than that of CD11b- UV-EC; this was confirmed by flow cytometric visualization of IL-10 protein in permeabilized cells. CD11b+ UV-EC macrophages secreted IL-10 protein into the supernatant at a level of 333 +/- 51 pg/10(6) cells, whereas UV-EC keratinocytes did not secrete detectable levels of IL-10 (n = 3), although UV did induce low levels of IL-10 mRNA and cell-associated protein in keratinocytes. Therefore, although human keratinocytes accumulate intracellular IL-10 after in vivo UV exposure, the most potent production and secretion of IL-10 in the epidermis seems to be that of UV-induced macrophages. Skin-infiltrating macrophage secretion of such a potent immunoregulatory cytokine may account for the delayed immunosuppressive environment of sunburned skin and the altered APC activity of the infiltrating macrophages.

Adult↗
PubMed1994

Atopic dermatitis: recent trends in pathogenesis and therapy.

Emerging concepts in the areas related to the pathogenesis and treatment of atopic dermatitis are reviewed. In particular, recent findings have revealed several key steps in the maintenance of a vicious circle of spongiotic dermatitis associated with elevated T-lymphocyte activation, hyperstimulatory Langerhans cells, defective cell-mediated immunity, and B-cell IgE overproduction. The discovery of specific IgE-binding structures on Langerhans cells provides a mechanism for Langerhans cells to capture and present IgE-targeted allergens to allergen-specific T cells. Furthermore, certain microbial allergens that tend to preferentially elicit IgE-type responses also elicit a T-cell response dominated by the IgE-inducing lymphokine interleukin 4. Repeated stimulation by activated Langerhans cells appears to induce just such a response. Abnormal biochemical responsiveness and mediator release by AD monocytes, mast cells, and eosinophils also participate in the sustainment or initiation of such a vicious circle, and contribute directly to the dermatitis as well. Developments in the areas of neuropeptides, genetics, microbial superantigens, and cytokine networks in the skin also appear to have promise in providing a rational link between immune defects and the inflammatory events in AD. Conventional therapy remains the mainstay of atopic dermatitis management; however, new therapies based upon the above concepts are being tested in clinical trials. Although the difficulty of objectively grading AD lesional activity and the high placebo response of AD patients hampers the interpretation of many reports, several types of approaches are coming into focus. The effectiveness of cyclosporin A, which targets T-cell activation and antigen presentation, indicates that additional agents with such activity should be effective, and verifies the criticality of these cells in AD pathogenesis. Therapy with biologic response modifiers, such as interferon gamma or thymopentin, is oriented toward normalization of imbalanced immune responsiveness, rather than direct suppression of the immune system. The mechanism of action of and toxicities of Chinese herbal mixtures require further investigation, but may reveal hitherto unconsidered avenues. Other recent therapeutic trials have focused on reduction of trigger factors, such as house dust mite exposure, foods, and the abnormal epidermal lipid barrier to irritation.

Dermatitis, Atopic↗
PubMed1994

Distinction of class II MHC+ Langerhans cell-like interstitial dendritic antigen-presenting cells in murine dermis from dermal macrophages.

Dermal cells are capable of initiating contact-hypersensitivity responses but the precise identification of the antigen-presenting cell within murine dermis is lacking. Class II major histocompatibility complex (MHC)+ cells with dendritic shape and lacking endothelial factor VIII but expressing the dendritic antigen-presenting cell marker NLDC-145 were observed in the perivascular and interstitial dermis of BALB/c and C3H/HeN skin. The heterogeneous class II MHC+ cells could be divided into two subsets: each was class II MHC+ CD45+ (bone marrow derived) GR-1- (non-neutrophil/macrophage) CD3- (non T), but one subset was CD11b+ (beta 2 integrin) and the other was CD11b-. Ultrastructural examination of class II MHC+ cells revealed the presence of a Langerhans cell-like/indeterminant cell subset with indented nuclei, dendritic morphology, active cytoplasm, and dense intermediate filaments. Phagolysomes and Birbeck granules were not observed in such cells, indicating these were distinct from dermal macrophages and from classical epidermal Langerhans cells, respectively. Cells with a monocyte/macrophage ultrastructural appearance were also noted, likely representing the class II MHC subset expressing CD11b and Ly6c (monocyte/endothelial antigen). Dermal cells in suspension were capable of processing and presenting large protein antigens to antigen-specific T-cell hybridomas; dermal cells also induced the syngeneic mixed lymphocyte reaction. The dermal antigen-presentation activities were totally abrogated by removal of class II MHC+ cells, but not by removal of CD11b+ cells or Ly6c+ cells, indicating that potent antigen-presenting cell activity was restricted to the class II MHC+ CD11b- Ly6c- subset (Langerhans cell-like/indeterminant cells). In conclusion, within a complex array of dermal leukocytes a murine dermal class II MHC+ cell population expressing a Langerhans cell-like/dendritic antigen-presenting cell phenotype and exhibiting potent antigen processing and presenting activity can be identified. The positioning of potent interstitial dendritic antigen-presenting cells at the interface of the vasculature with the dermal interstitium provides rapid access to an antigen-presenting cell as T cells first egress into the skin.

Animals↗
PubMed1994

Retinoic acid upregulates human Langerhans cell antigen presentation and surface expression of HLA-DR and CD11c, a beta 2 integrin critically involved in T-cell activation.

Immunomodulatory effects of retinoids may be part of their anti-carcinogenic and anti-inflammatory properties. We studied the in vivo effects of retinoic acid (RA) on antigen-presenting activity of human epidermal Langerhans cells and on accessory cell activity of keratinocytes. Two skin sites from each volunteer were treated in vivo with 0.1% RA or vehicle, respectively, once a day for 4 d. RA-treated epidermal cell (RA-EC) alloantigen presentation to CD4+ T cells in each volunteer tested was consistently greater than that induced by vehicle EC. However, this increased antigen-presenting activity did not lead to autoreactive CD4+ T-lymphocyte proliferation. Elevated unfractionated epidermal antigen-presenting activity of RA-EC was not due to increased keratinocyte major histocompatibility complex (MHC) or intercellular adhesion molecule expression or to other keratinocyte accessory signaling, because incubation of CD1a-fluoroscence-activated cell sorter (FACS)-purified RA-EC inhibited alloantigen presentation, presumably through increased keratinocyte transforming growth factor-beta. By contrast, Langerhans cell function was upregulated; FACS-purified CD1a+ Langerhans cells derived from RA-EC displayed a markedly increased ability, relative to Langerhans cells from vehicle EC, to present alloantigen to T cells. Triple color flow-cytometric analysis of RA-EC and vehicle EC suspensions revealed that RA treatment did not modify the number of DR+ and CD1a+DR+EC, but did result in statistically significant increases in Langerhans cells expression of HLA-DR, CD11c, and CD1c. Another novel finding was that HLA-DR-dependent Langerhans cells antigen-presenting activity in both normal and RA-treated skin was completely blocked by anti-CD11c antibody. Thus, retinoid upregulation of antigen-presenting activity may be due to upregulation of Langerhans cell CD11c, as well as class II MHC. Upregulation of cutaneous immune responsiveness in human skin without autoreactivity has not (to our knowledge) been reported previously, and the Langerhans cell phenotypic and functional state achieved is distinct from previously reported states of Langerhans cell activation.

Antigen Presentation↗
PubMed1994

High frequency of HLA-DQB1*0301 allele in patients with pure ocular cicatricial pemphigoid.

Two factors, is classification and its immunogenetics, may have contributed to an incomplete understanding of the pathogenic mechanism in the disease group commonly termed 'cicatricial pemphigoid'. We have previously demonstrated that pure ocular cicatricial pemphigoid (OCP) is a unique clinical and immunopathological entity. In an effort to better define the immunogenetic characteristics for patients with pure OCP, we performed HLA typing for the class II MHC gene HLA-DQB1*0301 allele, by amplifying genomic DNA extracted from patients with polymerase chain reaction, followed by hybridization with a sequence-specific oligonucleotide probe on dot-blotted and Southern-blotted amplified DNA samples. Ninety percent (9/10) of patients with pure OCP had the DQB1*0301 allele, in contrast to 52% (17/33) of normal individuals who had the DQB1*0301 allele. The high frequency of the HLA-DQB1*0301 allele in patients with pure OCP may point to a distinct immunogenetic pattern and possibly a distinct pathomechanism for the disease.

Alleles↗
PubMed1994

Acute erythroderma as an exclusion criterion for idiopathic CD4+ T lymphocytopenia.

BACKGROUND: Idiopathic CD4+ T lymphocytopenia is defined as a CD4+ T lymphocytopenia of less than 0.3 x 10(9)/L that is not associated with human immunodeficiency virus, other immunodeficiency, or immunosuppressive therapy. The associated clinical course and laboratory findings are variable. We describe a subset of patients whose peripheral CD4+ T-lymphocytopenia was transient, and suggest a pathomechanism for this phenomenon. OBSERVATIONS: We describe three patients with cutaneous T-cell lymphoma, atopic dermatitis, or psoriasis in whom acute erythroderma was concomitant with a peripheral CD4+ T lymphocytopenia that normalized after resolution of the erythroderma. Immunoperoxidase staining of skin biopsy specimens and quantitative estimation of CD4+ T lymphocytes in the cutaneous and peripheral blood compartments demonstrated that the peripheral CD4+ T lymphocytopenia in these cases most probably resulted from sequestration of CD4+ T lymphocytes in the skin. The skin of an erythrodermic patient appears capable of sequestering 10(10) to 10(11) CD4+ T lymphocytes, whereas the peripheral blood compartment contains in the range of 10(9) CD4+ T lymphocytes. CONCLUSIONS: We propose that CD4+ T lymphocytopenia can occur as a result of acute erythroderma of multiple causes and that acute erythroderma associated with transient CD4+ T lymphocytopenia be considered as an exclusion criterion for idiopathic peripheral blood CD4+ T lymphocytopenia.

Adult↗
PubMed1994

A novel immune-mediated subepidermal bullous dermatosis characterized by IgG autoantibodies to a lower lamina lucida component.

BACKGROUND: Immune-mediated subepidermal bullous dermatoses characterized by in vivo-bound linear IgG deposition at the cutaneous basement membrane zone include bullous pemphigoid, ocular cicatricial pemphigoid, anti-bullous pemphigoid antigen mucosal pemphigoid, anti-epiligrim mucosal pemphigoid, epidermolysis bullosa acquisita, and the bullous eruption of systemic lupus erythematosus. In this article, we describe a novel IgG-mediated bullous dermatosis. OBSERVATIONS: Clinically, a unique nonscarring dermatosis was characterized by the sudden onset of extensive bullae and erosions on mucous membrane and skin, resembling toxic epidermal necrolysis or pemphigus vulgaris. Histologically, the patient's skin lesion demonstrated neutrophilic papillary dermal infiltration and subepidermal blister formation, resembling dermatitis herpetiformis. Immunopathologically, there was linear IgG and C3 deposition at the skin basement membrane zone. The patient responded well to prednisone and azathioprine immunosuppression and has achieved a lasting remission without further therapy. Further immunologic investigations revealed that this unique dermatosis is distinct from all other known IgG-mediated subepidermal bullous dermatoses. CONCLUSIONS: This novel deep lamina lucida pemphigoid can be distinctly termed anti-p105 pemphigoid on the basis of antigenic specificity of the autoantibodies. Although this novel dermatosis resembles toxic epidermal necrolysis clinically, prudent use of diagnostic immunofluorescence studies can clearly delineate its immunologic nature. Prompt recognition of this unique dermatosis and timely initiation of appropriate immunosuppressive therapy could be life-saving for those patients suffering from this dermatosis.

Autoantibodies↗
PubMed1993

Heterogeneous populations of class II MHC+ cells in human dermal cell suspensions. Identification of a small subset responsible for potent dermal antigen-presenting cell activity with features analogous to Langerhans cells.

Little is known regarding the identification, classification, and function of class II MHC+ dendritic cells in the perivasculature of human connective tissues, such as the dermis. We developed a method for preparing papillary dermal cell suspensions from human keratome strips. Among the class II MHC+ populations of the dermis identified using triple color flow cytometry, cells of monocyte/macrophage lineage (CD45+ CD1- CD11b+ CD11clo-mid CD32+ CD36+ or - CD11a-) and mesenchymal cells of non-bone marrow origin (CD45-) were identified and characterized. Another distinct class II MHC+ subset was identified, which expressed a number of features analogous to epidermal Langerhans cells (LC) and other dendritic APC. These were a numerically minor population comprising only 2.7% +/- 1% (n = 7) of dermal cells. Like LC, they express HLA-DR, CD45, CD1a (albeit at a lower level of expression), CD1c, and CD32 and lack constitutive CD11a or ICAM-1. In contrast to LC, this dermal CD1a+CD1c+ subset expresses CD1b, CD11b, a higher level of CD11c, and intracytoplasmic factor XIIIa. Alloantigen presentation by unfractionated dermal cells was reduced by prior removal of this CD1b+ subset to the same degree achieved by removal of the entire DR+ population (20% of dermal cells), indicating that this was the critical DR+ subset. Cocultures of CD4+ T lymphocytes with cells sorted by flow cytometry into CD1c+DR+, CD1c-DR+ and DR- dermal cell subsets positively identified the CD1c+DR+ population as the most potent of potential APC subsets in human dermis. Thus, in distinction to other dermal macrophage and mesenchymal subsets with elongate morphology, the CD1aloCD1b,c+CD11c(hi)CD11b+CD32+DR+ population in human dermis is highly analogous to cells of LC/dendritic APC lineage in its phenotype and in its exclusive ability to potently present Ag to T lymphocytes. These studies identify and characterize the APC subset most potent in inducing activation of T cells initially entering the perivasculature of human dermis to be of LC/dendritic APC, and not tissue macrophage, lineage.

Adult↗
PubMed1993

Flow cytometric identification of proliferative subpopulations within normal human epidermis and the localization of the primary hyperproliferative population in psoriasis.

In this study we define the proliferative compartments of in vivo human epidermis, using specific antibodies related to cell differentiation (beta 1 and beta 4 integrins and K1/K10 differentiation keratins) and cell cycle (proliferating cell nuclear antigen [PCNA]) in combination with flow cytometric quantitation of the DNA content and optical characteristics of the cells. The beta 1 integrin (CD29) marked both of the potentially proliferative subsets in normal epidermis. One subset of normal epidermis is CD29+ K1/K10-, which was predominantly basal, and found to be comprised of slow cycling, small cells with primitive cytoplasmic organization. The vast majority (95.5%) of these cells were in a quiescent state (G0/early G1) as indicated by their lack of the cyclin, PCNA. The other proliferative subset of normal epidermis was CD29+ K1/K10+, which was suprabasal and occasional basal, highly proliferative, larger in size, and which exhibited a more complex cytoplasmic structure. Because early differentiation (K1/K10 expression) has begun in the CD29+ K1/K10+ subset, it is highly likely that they represent the proliferative population which is capable of transiently amplifying itself before terminal differentiation. Within lesional psoriatic epidermis, similar proliferative cell populations were present as in normal epidermis, and the hyperproliferative defect was localized to the beta 1 and beta 4 integrin+, K1/K10- populations, which in normal epidermis is basally located and quiescent with regard to cell cycle. In psoriatic epidermis, a six- to sevenfold increase in the number of cells in the S/G2+M phase of cell cycle was found among CD29+ K1/K10- cells (p < 0.05). Furthermore, all lesional K1/K10- cells showed high PCNA positivity, indicating that all these cells had been recently induced into cell cycle. By contrast, the proportion of cycling cells among lesional psoriatic CD29+ K1/K10+ keratinocytes was similar to normals. Anti-HLA-DR, CD45, and vimentin antibodies were used to concomitantly track the proliferative states of Langerhans cell, melanocyte, and infiltrating leukocyte populations. In normal epidermis, the cycling fractions (cells in S/G2/M phase) of these cells were similar to the CD29+K1/K10- keratinocytes, whereas in lesional epidermis their cycling pools were increased relative to normal, but not so much as the proliferative fractions of psoriatic CD29+ K1/K10- keratinocytes. These data demonstrate the use of simultaneous analysis of integrin expression, differentiation keratins, cyclin, cell cycle status, and optical characteristics of freshly isolated human epidermal cells. Such analysis allowed the physical identification and quantification of cy cling populations in normal human skin, and has enabled the precise location of the primary epidermal proliferative defect in psoriasis.

Antigens, CD↗
PubMed1993

Immune-mediated subepithelial blistering diseases of mucous membranes. Pure ocular cicatricial pemphigoid is a unique clinical and immunopathological entity distinct from bullous pemphigoid and other subsets identified by antigenic specificity of autoantibodies.

BACKGROUND AND DESIGN: There is much confusion in the clinical classification of immune-mediated subepithelial blistering diseases of mucous membranes. We conducted a 6-year comprehensive study to better classify this heterogeneous disease group. Indirect immunofluorescence was performed on a salt-split-skin substrate to detect circulating antibasement membrane antibodies (n = 47). Serologic reactivity against cultured keratinocyte antigens was examined by immunoblots (n = 38) and immunoprecipitation (n = 15). The results were correlated with the clinical features and direct immunofluorescence data of the entire patient group (n = 87) without preassignment of clinical diagnoses. chi 2 Statistical analyses compared these results with those of the classic bullous pemphigoid group (n = 36). RESULTS: When compared with the bullous pemphigoid patients, a subset of patients with combined oral mucosal and skin lesions demonstrated marked similarity in direct and indirect immunofluorescence findings and in serologic reactivity to bullous pemphigoid antigens. By contrast, a subset of patients with only ocular lesions exhibited significantly lower in vivo deposits of IgG and C3, higher deposits of fibrin, virtual absence of circulating antibodies, and negative serologic reactivity to bullous pemphigoid antigens. CONCLUSIONS: Ocular patients without skin or mouth lesions, in particular those with negative indirect immunofluorescence, should be distinctively classified as ocular cicatricial pemphigoid, a unique clinical and immunopathologic entity. Patients with mucous membrane involvement who also demonstrate skin lesions and antibodies to the root of salt-split-skin substrate should be classified as anti-BP Ag mucosal pemphigoid, even though they may exhibit severe oral and/or ocular diseases. The remaining mucous membrane patients are heterogeneous. Some can be classified on the basis of autoantibodies to other basement membrane determinants, or if serum autoantibody negative, on the basis of clinical features (ie, pure oral mucosal pemphigoid or overlapping mucosal involvement).

Autoantibodies↗
PubMed1993

The mechanisms of action of cyclosporin A in the treatment of psoriasis.

This article describes the effects of cyclosporin A (CsA) on the immunopathological mechanisms operative in psoriasis, a human skin disease. The main focus is the effect of CsA on keratinocytes, T cells and antigen-presenting cells, the key players in lesional psoriatic skin. The effect of CsA on other cells, such as neutrophils and endothelial cells, which are important in the maintenance of psoriasis, are also discussed.

Antigen-Presenting Cells↗