PubMed Health⌕ Search

Biomedical subjects

B Volc-Platzer

Publications and source records attributed to B Volc-Platzer.

49 records · Page 3Linked to original sources

Sequential immunohistologic analysis of the skin following allogeneic bone marrow transplantation.

Graft-vs-host disease is generally viewed as an immunologically mediated disease. In search of additional tools for early diagnosis and an elucidation of the pathogenic mechanisms we investigated the expression kinetics of hemopoietic differentiation and class II alloantigens on both resident and passenger skin cells after bone marrow transplantation. HLA-DR antigens, which are found normally on the dendritic epidermal Langerhans cells only, are synthesized and expressed by keratinocytes within lesions of acute and chronic cutaneous graft-vs-host disease. Within non-lesional skin, however, during the course of cutaneous graft-vs-host eruptions, no clear cut expression of keratinocyte-bound HLA-DR antigens can be identified, suggesting that this phenomenon is locally restricted rather than generalized. Furthermore, our data indicate that within lesions clinically suggestive of cutaneous graft-vs-host disease but lacking diagnostic histopathologic criteria, KC-bound HLA-DR antigens can be readily identified. The second class II alloantigens investigated within the epidermis, the HLA-DQ antigens, were seen on Langerhans cells only and were not or only rarely detectable on keratinocytes. Several subtypes of CD3+ T lymphocytes were present in the epidermis of acute graft-versus-host lesions: one portion of CD3+ T lymphocytes also displayed the CD8 antigen; one portion, mainly localized within the basal layer, displayed the CD8 and/or the CD4 antigen; and one portion did not allow identification of CD8, CD4, or Leu7 antigens. In chronic cutaneous graft-versus-host lesions CD3+/CD8+ T lymphocytes predominated. CD1+ epidermal Langerhans cells were reduced in number and appeared rounded with blunt dendrites both in acute and chronic cutaneous graft-vs-host disease, but also, though to a lesser extent, within normal appearing skin from bone marrow transplanted patients without cutaneous graft-vs-host disease.

Adolescent↗

Recombinant gamma interferon and in vivo induction of HLA-DR antigens.

Recombinant human IFN-gamma, used for treatment of melanoma and renal carcinoma, was found to induce HLA-DR expression on human keratinocytes in vivo. HLA-DR antigens bound to keratinocytes of the basal and suprabasal layers of the epidermis were observed after intramuscular or intravenous injections of 0.5 mg/kg body weight IFN-gamma, 3 times a week. Keratinocyte-bound HLA-DR antigens were first observed at the beginning of the third or fourth week of treatment, but HLA-DQ and HLA-DP antigens were never detected on keratinocytes. The intracytoplasmic constant (gamma) chain of the class II molecules was also not detectable within the keratinocytes. Patients who received IFN-alpha 2 therapy, did not exhibit keratinocyte-bound HLA-DR antigens.

Female↗

Defective intralesional interferon-gamma activity in patients with lepromatous leprosy.

Cryostat sections of full-thickness skin biopsies from 21 patients along the whole spectrum of leprosy were subjected to immunohistological examination with special regard to defective lymphokine production. There was an inverse relationship between intra-lesional IL-1 reactivity and IL-2R expression, in that the latter was markedly observed in tuberculoid lesions. Whenever epithelioid cell containing granulomas were present in paucibacillary forms, significant reactivity within the central phagocytic cells with the monoclonal antibody directed against interferon-gamma was detectable. The keratinocytes covering tuberculoid lesions abundantly expressed class II alloantigens (HLA-DR antigens), indicating high intra-lesional interferon-gamma activity. In contrast, multibacillary forms revealed significant anti-IL-1 reactivity within the cellular infiltrate. IL-2R bearing cells were virtually absent as was anti-HLA-DR reactivity of the keratinocytes, underlining a defective intra-lesional interferon-gamma activity.

Epidermal Cells↗

Survival and quality of life in 23 patients with severe aplastic anemia treated with bone marrow transplantation (BMT).

Survival and quality of life are reported in 23 pretransfused patients with severe aplastic anemia (SAA) who underwent bone marrow transplantation (BMT). The projected survival is 76% with 18 of 23 patients being alive 332 to 1677 days post graft (median: 842). 5 patients died between day 4 and 416. 12 of 17 patients at risk developed chronic graft versus host disease (GVH-D). 4 of these patients have a diminished quality of life due GVH-D related disabling manifestations. Autologous haemopoietic recovery was excluded in all patients by the demonstration of haemopoietic chimerism. We recommand age-adapted rejection prophylaxis; such strategy may help to diminish disabling graft versus host disease in otherwise haematologically reconstituted survivors.

Adolescent↗

Differential expression of class II alloantigens by keratinocytes in disease.

The purpose of this study was to determine whether keratinocytes in certain disease states such as cutaneous T-cell lymphoma and lichen planus, express HLA-DR antigens (corresponding to the murine I-E antigens) only or whether they are also capable of expressing HLA-DQ antigens (analogues of the murine I-A antigens). Cryostat sections from 11 biopsies from cutaneous T-cell lymphoma and from 11 lichen planus biopsy specimens were submitted to indirect immunofluorescence and a 4-step immunoperoxidase method. This consists of applying monoclonal antibodies recognizing HLA-DR and HLA-DQ molecules and the intracytoplasmic invariant chain of the class II molecules. In 8 of the 11 cutaneous T-cell lymphoma specimens and in 3 of the 11 lichen planus biopsies concomitant expression of HLA-DR and HLA-DQ molecules by keratinocytes was detectable with the immunoperoxidase method. However, with the indirect immunofluorescence technique HLA-DQ antigens on keratinocytes could not be detected. The simultaneous expression of surface-bound HLA-DR antigens and intracytoplasmic gamma-chains was demonstrable in all cases investigated and with both the immunohistologic methods applied.

Epidermis↗

Human epidermal cells synthesize HLA-DR alloantigens in vitro upon stimulation with gamma-interferon.

Under certain pathologic conditions, human keratinocytes synthesize and express HLA-DR antigens. Assuming that soluble mediators might be responsible for this phenomenon, differentiating, primarily DR-keratinocytes were grown in the presence or absence of mixed leukocyte culture supernatants and tested for Ia antigen expression. After 6 days of culture, keratinocytes displayed surface-bound HLA-DR alpha/beta complexes when exposed to mixed leukocyte culture supernatants but not when cultured in media alone. These HLA-DR moieties on keratinocytes result from active biosynthesis as evidenced by the demonstration of the intracytoplasmic HLA-DR gamma (invariant) chain within these cells. In view of reports that interferon-gamma promotes Ia-production in a variety of cell types, we reasoned that this lymphokine might be responsible for the Ia-inducing property of mixed lymphocyte culture supernatants. Indeed, recombinant interferon-gamma, but not interferon-alpha or interleukin-2, proved to be a potent stimulator of Ia expression by keratinocytes. The further finding that this event can be prevented by the addition of a monoclonal anti-interferon-gamma antibody strongly suggests that this cytokine is directly responsible for HLA-DR production by keratinocytes. The interferon-gamma-induced acquisition of HLA-DR antigens by primarily DR-keratinocytes may provide a useful tool to study the role of these alloantigens in T-cell activation and may also add to our understanding of mechanisms operative in epidermal cell-T-cell interactions.

Antibodies, Monoclonal↗

Evidence of HLA-DR antigen biosynthesis by human keratinocytes in disease.

As opposed to normal human skin where HLA-DR expression is restricted to the Langerhans cell (LC) population, HLA-DR, but not HLA-DS antigens can be readily detected on keratinocytes (KC) in certain disease states, i.e., cutaneous T cell lymphoma (CTCL), graft-vs-host disease (GVHD), and lichen planus (LP). To clarify the cellular origin of KC-bound HLA-DR antigens, we used a monoclonal antibody directed against determinants solely expressed on the cytoplasmic HLA-DR gamma chain (VIC-Y1) and observed that, by immunofluorescence, KC displaying HLA-DR alpha/beta complexes on their surface uniformly displayed cytoplasmic VIC-Y1 reactivity. In view of the crucial role of the gamma chain for HLA-DR biosynthesis, we conclude that HLA-DR antigens on KC are actively synthesized by these cells.

Epidermis↗

[Immunohistochemical studies on the association between hepatitis B surface antigen and primary hepatocellular carcinoma (author's transl)].

In many geographical areas especially in African and South-east-Asian countries hepatitis B virus infection is considered to be a major etiological factor in the development of primary hepatocellular carcinoma. 107 autopsy- and 15 biopsy-specimens were studied by means of immunohistochemistry [peroxidase-antiperoxidase-(PAP-)method] to demonstrate the association between primary hepatocellular carcinoma and hepatitis B surface antigen (HBsAg). HBsAg was found in 8 of 107 tumour specimens (7.4%) and liver cirrhosis in 102 of the 107 autopsy specimens with hepatocellular carcinoma (95%). 10 of the 15 biopsy-specimens showed neoplastic and non-neoplastic liver tissue, and in 2 of these 10 cases HBsAg was found. Liver cirrhosis could be seen in 9 of those 10 specimens. HBsAg was also studied in 90 cases with liver cirrhosis and was found to be positive in 2 of them (2,2%). HBsAg associated with primary hepatocellular carcinoma was only found in non-neoplastic liver cells of cirrhotic livers. Our studies indicate that in our geographical area the association of HBsAg with primary hepatocellular carcinoma is much less conspicuous than in Asian, African and even Southern European communities.

Africa↗

Different keratin polypeptides in epidermis and other epithelia of human skin: a specific cytokeratin of molecular weight 46,000 in epithelia of the pilosebaceous tract and basal cell epitheliomas.

Cytokeratin polypeptides of human epidermis, of epithelia microdissected from various zones of the pilosebaceous tract (outer root-sheath of hair follicle, sebaceous gland), and of eccrine sweat-glands have been separated by one- and two-dimensional gel electrophoresis and characterized by binding of cytokeratin antibodies and by peptide mapping. The epithelium of the pilosebaceous tract has three major keratin polypeptides in common with interfollicular epidermis (two basic components of mol wts 58,000 and 56,000 and one acidic polypeptide of mol wt 50,000); however, it lacks basic keratin polypeptides in the mol wt range of 64,000-68,000 and two acidic keratin-polypeptides of mol wts 56,000 and 56,500 and contains an additional characteristic acidic cytokeratin of mol wt 46,000. Another cytokeratin polypeptide of mol wt 48,000 that is prominent in hair-follicle epithelium is also found in nonfollicular epidermis of foot sole. Both epidermis and pilosebaceous tract are different from eccrine sweat-gland epithelium, which also contains two major cytokeratins of mol wts 52,500 and 54,000 (isoelectric at pH 5.8-6.1) and a more acidic cytokeratin of mol wt 40,000. A striking similarity between the cytokeratins of human basal-cell epitheliomas and those of the pilosebaceous tract has been found: all three major cytokeratins (mol wts 58,000; 50,000; 46,000) of the tumor cells are also expressed in hair-follicle epithelium. The cytokeratin of mol wt 46,000, which is the most prominent acidic cytokeratin in this tumor, is related, by immunological and peptide map criteria, to the acidic keratin-polypeptides of mol wts 48,000 and 50,000, but represents a distinct keratin that is also found in other human tumor cells such as in solid adamantinomas and in cultured HeLa cells. The results show that the various epithelia present in skin, albeit in physical and ontogenic continuity, can be distinguished by their specific cytokeratin-polypeptide patterns and that the cytoskeleton of basal-cell epitheliomas is related to that of cells of the pilosebaceous tract.

Basal Cell Carcinoma↗

High dose intravenous immunoglobulin (IVIG) in dermatomyositis: clinical responses and effect on sIL-2R levels.

An open study was conducted to identify and investigate dermatomyositis patients who benefit from IVIG treatment, based on dermatological criteria, myositis-related symptoms and immune/inflammatory parameters. 19 patients (16 females and three males, ages 31-84) suffered from dermatomyositis, and 4/19 patients had paraneoplastic dermatomyositis. We monitored the disease activity by documenting the clinical symptoms, recording muscle-related parameters (electromyography, serum creatine kinase, histopathology), and by determining circulating autoantibodies and serum levels of IL-6, sIL-2R, sTNF-a-R, sICAM-1, and sCD8. 7/19 patients responded to IVIG. They had severe skin but only moderate muscle involvement, no autoantibodies, and no malignancy. IVIG-nonresponders had severe skin and muscle disease, concomitant with autoantibodies and/or malignancy. sIL-2R levels were initially elevated in all patients but reverted to normal in IVIG-responders only. Creatine kinase-levels and other parameters did not correlate with disease activity and/or treatment response. IVIG is effective in selected dermatomyositis patients. sIL-2R serum levels appear to be useful predictors of IVIG-induced treatment response and disease activity.

Adult↗