Isolation, purification and quantification of phenolic glycolipid-1 from human leprosy skin tissues.

Phenolic glycolipid-I, a marker lipid of Mycobacterium leprae, was isolated from skin biopsies obtained from untreated lepromatous leprosy patients by silicic acid and florisil column chromatography and purified by thin layer chromatography. Tissues with varying bacillary loads were analysed for their phenolic glycolipid content. A good correlation was observed between the bacillary population of the tissues and the phenolic glycolipid content.

S-100 protein and immunoperoxidase technique as an aid in the histopathologic diagnosis of leprosy.

The histopathologic diagnosis of leprosy in the tuberculoid type (TL) and in the indeterminate group (IL) may be difficult and frequently unfeasible. The detection of the impairment of cutaneous nerve branches by the inflammatory reaction may permit the diagnosis of TL over other skin granulomas. In an attempt to overcome these diagnostic difficulties in the lesions with no bacilli and without obvious damage to nerve branches, we utilized the immunoperoxidase technique with S-100 protein as the nerve marker. Two groups were selected: Patients (group 1) with TL confirmed by the presence of bacilli, and patients (group 2) with a clinical diagnosis of TL not confirmed by histopathology. The slides treated by S-100 in group 2 showed that 8 cases (9 total) were confirmed to have TL on the basis of the nerve alteration observed by the immunoperoxidase technique. These data obtained in the present studies show that use of the immunoperoxidase technique for the detection of S-100 protein to visualize peripheral nerves represents an efficient auxiliary aid in the diagnosis of leprosy.

C-reactive protein and apoB containing lipoproteins are associated with Mycobacterium leprae in lesions of human leprosy.

Skin biopsies from patients with leprosy across the spectrum from tuberculoid (TT) to lepromatous (LL), including histoid lepromas and erythema nodosum leprosum (ENL) reactions, were stained immunohistochemically for the presence of C-reactive protein (CRP) and the apolipoprotein, apoB. Mycobacterium leprae bacillary material comprising cell walls, cytoplasmic and soluble components was present with increasing abundance towards the lepromatous end of the spectrum and always stained positively with anti-CRP. M. leprae from armadillos did not stain with anti-human CRP indicating that the staining of M. leprae in human tissues was not due to a cross-reaction between anti-CRP and the organism itself. When CRP was present in large amounts apoB was also demonstrated in the same distribution. CRP was detected on bacilli and their degradation products within the cytoplasm of macrophages even in the absence of a raised serum CRP level in some ENL patients and also in two cases of advanced resolving lepromas. These findings demonstrate remarkable persistence of CRP in association with M. leprae in vivo, and raise intriguing questions about the possible role of CRP in relation to the handling of leprosy bacilli.

Detection of mycobacterial lipids in skin biopsies from leprosy patients.

Thin-layer chromatography was used to compare lipid extracts from lepromatous skin biopsies with those from normal skin and from Mycobacterium leprae purified from armadillo spleen. Several lipids were found in infected skin which were absent from normal skin but corresponded to lipids present in the purified M. leprae. These included mycolic acids, a 6-deoxyhexose-containing lipid (glycolipid I) and a wax ester (possibly related to the Mycobacterium tuberculosis wax, phthiocerol dimycocerosate). Unlike Mycobacterium lepraemurium, M. leprae contained no C-type mycosides. In terms of lipid profile, M. leprae from armadillo spleen showed the same characteristics as bacilli from human skin samples. Quantitative analysis of mycobacterial lipids in lepromatous skin biopsies indicated that their concentrations were much higher than would be predicted from the number of acid-fast bacilli present. Accumulation of lipid debris from dead M. leprae could provide a protective environment in infected cells for remaining viable bacilli.

Lactate dehydrogenase zymograms of skin biopsies in patients with leprosy. A preliminary report.

LDH isoenzymes were studied in tissue extracts of 78 cases of leprosy. All 25 control tissues showed five LDH isoenzymes corresponding to those of human sera. All tissues from the leprosy cases showed five similar bands. Seventeen cases showed additional LDH isoenzymes (anomalous bands). In 12 cases there was a single extra band with an eF value of either 0.125 +/- 0.015 or 0.525 +/- 0.015, and five cases showed both these bands. Additional bands were observed only in cases positive for acid-fast microorganisms (17 of 27 cases), and their presence correlated well with bacterial load (as judged by the BI) and viable organisms (as judged by the MI). Four cases with a high BI and MI did not show anomalous bands, however. A plausible explanation for these bands is that they originate from viable M. leprae.

In vivo study of trace elements in leprous skin.

The skin of leprous patients at various stages of the disease was investigated by diagnostic x-ray spectrometry, In the active stage raised iron and slightly raised zinc levels were found. The usefulness of the method in skin investigation is foreseen.

Histochemistry of B663 pigmentation: ceroid-like pigmentation in macrophages.

Histochemical studies were made of pigmented cutaneous lesions from three cases of lepromatous leprosy treated with B663 to determine the nature and histogenesis of the brown pigmentation which develops as a side effect of the drug. One case of DDS-treated leprosy and four cases of untreated leprosy were also investigated histochemically as controls. The brown pigmentation of the skin is due to deposition of a ceroid-like substance in the macrophages, which is a yellowish-brown, acid-fast lipid pigment. It is insoluble in fat solvents and accepts lipid dyes even after lipid extraction by fat solvents. The macrophages in the B663-treated leprosy contain more neutral fat and less phospholipid than the untreated lepromatous leprosy tissues. Ceroid in the macrophages probably originated from unsaturated fatty acids of the leprosy bacilli through oxidation or their binding with the drug. Crystals of the drug were not found in the macrophages in this series, even on the tissues embedded in carbowax or frozen sections.

Long-spacing collagen in skin biopsies from patients with lepromatous leprosy.

In the course fo evaluating the effect of different drugs on the morphology of Mycobacterium leprae (Edwards, Draper & Draper, 1972) and on the phagocytic cells containing these organisms (Edwards, 1973), an unusual feature was observed in the dermal connective tissue of skin biopsies obtained from some of the patients. Variable amounts of an extracellular, cross-striated osmiophilic material were present in the dermis. The purpose of this communication is to describe the banded substance observed in the extracellular space of the lepromatous skin and to compare it briefly with similar substances and structures reported to occur elsewhere.

Histochemical study of Erythema nodosum leprosum (ENL) lesions.

A histochemical study of ENL lesions was performed on skin biopsies from 14 leproma-tous patients. There was: 1) the presence of moderate amounts of PAS positive diastase resistant materials, acid mucopolysaccharide, neutral fat, phospholipid, aryl sulfatase and acid phosphatase in areas around and away from reactional sites; 2) the presence of slight amounts or complete absence of these materials within areas of acute inflammation. These changes were interpreted as the result of solubilization and leakage of hydrolytic enzymes into the surrounding tissue. A possible role of lysosomal enzymes in the pathogenesis of ENL lesions is discussed.

Trophic skin ulceration of leprosy: skin and serum zinc concentrations.

Skin and serum zinc measurements have been made in patients with leprosy with and without trophic skin ulceration and in several other groups. Serum zinc concentrations were decreased in leprosy irrespective of the presence or absence of skin ulceration. Serum zinc concentrations in leprosy were also unrelated to smears positive for Mycobacterium leprae and to the clinical type of leprosy. Since a decrease of the serum zinc was also found in patients with dermatitis herpetiformis and pulmonary tuberculosis it seems likely that the decreased serum zinc in leprosy is a nonspecific metabolic consequence of chronic skin and internal disease. The mean skin zinc concentration in leprosy did not differ significantly from the corresponding value in control subjects, the lack of agreement between serum and skin concentrations being possibly related to the presence of nonexchangeable keratin-bound zinc in skin. Though the clinical significance of lowered serum zinc concentrations in leprosy is uncertain therapeutic trials of zinc treatment in leprosy with trophic skin ulceration seem justifiable.