SEARCH · PubMed Health

Results for “LEPROMIN”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

PubMedDate not supplied

Sub-clinical infection with Mycobacterium leprae in household contacts of leprosy.

870 household contacts of leprosy patients were examined for sub-clinical infection with M. leprae by smear (skin and nasal), lepromin and FLA-ABS tests. 0.6%, 3.3%, 71.5% and 14.4% of the contacts were found to be positive for skin smear, nasal smear, lepromin and FLA-ABS tests respectively. An analysis of the results revealed that 4% of the lepromin positive contacts and 3.6% of the lepromin negative contacts were positive to both FLA-ABS and skin or nasal smear.

Adolescent↗

PubMed1989

Immunoepidemiological studies on subclinical infection among leprosy household contacts in Thailand.

Three-thousand-fourteen leprosy house-hold contacts in Thailand were surveyed by their personal history, physical examination, and immunological tests. The results were compared with those obtained from villagers in leprosy-endemic and nonendemic areas. The percentages of young people, students, children and grandchildren of the patient, the contacts of multibacillary leprosy cases, long duration of contact, BCG vaccination, FLA-ABS and Dharmendra's lepromin-positive responders were significantly higher in the household contacts than those in the villagers. The percentages of neural and dermal symptoms were not significantly different between the household contacts and the villagers in the endemic area, but the percentages were higher than those of the villagers in the nonendemic area. A PPD skin test was more frequently negative in the former two groups than in the latter. Both FLA-ABS and lepromin tests showed a significant correlation with the age of the contacts, their occupations, blood relation to the patient, the duration of contact, BCG vaccination, dermal signs such as an ill-defined plaque or macule with or without sensory loss, but did not correlate with sex, type of leprosy in the patient, or other skin diseases. The FLA-ABS test in the house-hold contacts and the villagers in an endemic area showed a significant correlation with the neural signs, such as enlargement of the peripheral nerve without sensory loss. These suspicious dermal and neural signs and symptoms were therefore considered signs of Mycobacterium leprae infection. The FLA-ABS test was sufficiently sensitive for detecting this infection and did not correlate with the lepromin or PPD skin tests. FLA-ABS-positive but lepromin-negative responders were found in 33.5% of the house-hold contacts. They were considered to be a high-risk group who may develop clinical leprosy. Nearly half of them were treated with dapsone or BCG according to the results of the PPD skin test. Follow up of these contacts, together with the remaining contacts without treatment, is in progress.

Adolescent↗

PubMed1988

Immunogenic "subunit" of the ICRC antileprosy vaccine.

The administration of a vaccine containing ICRC bacilli, which is currently undergoing clinical trials in India, induces persistent lepromin conversion in lepromatous leprosy (LL) patients and lepromin-negative healthy subjects, with "upgrading" of tissue response in the former. A sonicate of ICRC bacilli, when subjected to gel-filtration chromatography using high-pressure liquid chromatography (HPLC), yields a high molecular weight glycolipoprotein (PP-I) with an apparent molecular weight of 10(6) daltons. PP-I, which brings about lepromin conversion in lepromin-negative healthy subjects, is a major immunogen of the organism, and carries epitopes for both B and T cells. A similar high molecular weight glycolipoprotein (PP-I Mycobacterium leprae) has been isolated from the sonicate of M. leprae. The two PP-I fractions exhibit a close antigenic relatedness at both B- and T-cell levels. However, they differ in their chemical composition and carry different charges. PP-I of ICRC is not only a good immunogen. Its high lipid content provides the necessary built-in adjuvant that would make it a good candidate for a "subunit" antileprosy vaccine. Also, since it carries epitopes for both B and T cells, PP-I ICRC could be used for "molecular engineering" to obtain molecules which selectively stimulate T-cell immunity which is the dominant host defense against M. leprae.

Adult↗

PubMed1987

Ability of the phenolic glycolipid-I antigen of M. leprae to elicit a positive Mitsuda response in the armadillo (Dasypus novemcinctus).

Three lepromin-positive armadillos and three lepromin-negative armadillos were tested intradermally with 100 micrograms of phenolic glycolipid-I (PGL-I) in 0.1 ml of normal saline. Positive delayed-hypersensitivity granulomas at 21 days in the lepromin-positive animals and negative responses in the lepromin-negative animals were obtained. These observations suggest that purified PGL-I is capable of eliciting cell-mediated immune or delayed-hypersensitivity responses in animals sensitized to Mycobacterium leprae.

Animals↗

PubMed1979

Behaviour of macrophages to Mycobacterium leprae. A tissue culture study.

Macrophage culture was performed on 45 healthy adults who were initially categorised on the basis of their Lepromin reactivity using Dharmendra antigen. There were 25 individuals in the Lepromin positive group and 20 in the Lepromin negative group. The cultures were challenged with M. leprae and the macrophages studied at varying time intervals of culture. No difference was evident in the behaviour of cultured macrophages to M. leprae in both the groups. The Lepra bacilli were phagocytosed by the macrophages and retained essentially intact till the termination of culture. The Lepromin reactivity of a healthy individual was not reflected on the macrophage function in vitro. The observations suggested against the possibility of an intrinsic genetically determined macrophage defect in dealing with M. leprae.

Adult↗

PubMed1983

Precipitation of type-I (upgrading) reaction in leprosy by skin testing with antigen and irritants.

Twenty patients of various types of leprosy were skin tested with lepromin, PPD and DNCB to assess their immunological status. Two of the twenty (18 BT; 2 BB) patients belonging to BT type developed signs of acute neuritis of sudden onset about 4 weeks after the test with DNCB, lepromin and PPD. The patients were on DDS therapy already for the last 3-4 months. Presumably DNCB, PPD or lepromin testing had precipitated the reaction. A suggestion is made that lepromin a lower concentration could be used initially and if it gives negative reaction, a higher concentration may be used as in case of PPD testing, particularly in TT and BT cases already put on treatment.

Adult↗

PubMedDate not supplied

[Immunological examination of patients with undetermined leprosy].

The immunological competence of eleven patients with undetermined leprosy was compared with that of ten normal volunteers of the same age and sex distribution; these controls have not had previous contact with leprosy. The following parameters were studied in peripheral blood cells: 1) percentage of lymphocyte bearing surface immunoglobulins, as revealed by immunofluorescence; 2) percentage of lymphocyte bearing complement receptors, as studied by antibody and complement coated erithrocyte rosetting; 3) percentage of T cells, as revealed by spontaneous sheep erithrocyte rosettes; 4) blastogenic and mytogenic response of cultured lymphocytes to PHA and 5) cell migration inhibition test using lepromine (80 x 10(6) bacilli/ml) as antigen. Skin reactions to lepromine were also assayed. In the six lepromine-positive patients with undetermined leprosy, no major immunological alterations could be detected. On the contrary, the five lepromine-negative patients showed important alterations which could well be considered as precursors of lepromatous leprosy.

Adult↗

PubMedDate not supplied

Cell-mediated immunologic status of healthy members of families with a history of leprosy.

The cell-mediated immune status of 20 apparently healthy children from families with a history of leprosy has been studied. They have been compared with 20 age- and sex-matched controls from families with no history of leprosy. Lymphocyte transformation tests using PHA, PPD and lepromin and skin tests to lepromin, PPD and candida were carried out. No evidence of a depression of cell-mediated immunity in the children from families with leprosy was obtained. The only two children giving a negative Mitsuda lepromin skin test both subsequently developed leprosy in the succeeding 16 months. One was classified histologically as indefinite lepromatous and the other as borderline lepromatous. This emphasizes the practical significance of a negative lepromin skin test in an endemic leprosy area as a prognosis of clinical lepromatous leprosy.

Adolescent↗

PubMed1995

Culture of nocardioform bacilli from leprosy patients & clinical evaluation of nocardioform bacilli derived antigen.

An antigen derived from cultured nocardioform bacilli was compared with Mitsuda lepromin in intradermal skin test reactions. Nocardioform bacilli were cultured in gelatin minimal medium from the tissue fluid of 85 lepromatous patients (56 M, 29 F). Of these, 65 samples showed uncontaminated growth of the organism, which were pooled for the manufacture of the test antigen. This antigen was intradermally tested in 50 untreated leprosy patients irrespective of the type, together with Mitsuda lepromin and sterile gelatin minimal media, which served as a control. No early reaction was observed at 72 h, while the late reaction at 28 days was positive in all patients in the Tuberculoid (TT) group with both antigens. Eighteen patients (81.8%) in the Borderline tuberculoid (BT) group reacted strongly to Mitsuda lepromin at 28 days, while 21 patients (95.5%) in this group showed a strong late reaction with the test antigen. The lepromatous (LL) group did not show any reaction with the two antigens. It is inferred that nocardioform bacilli are easy to cultivate, and that the test antigen compares well with Mitsuda lepromin.

Actinomycetales↗

PubMed1983

A quick method of demonstrating bacillaemia in patients with lepromatous leprosy and ultrastructural studies of the circulating acid-fast bacilli.

While studying circulating immune complexes (CIC) in the sera of lepromatous patients by the polyethylene glycol (PEG) precipitation technique, we found (by light microscopy) abundant acid-fast bacilli (AFB), morphologically similar to those seen in slit skin smear preparations from these patients, precipitated with the PEG precipitated materials. Both solid and non-solid AFB could be readily identified. Ultrastructures of these AFB in the PEG aggregates showed some similarity with those detected in the PEG precipitates prepared from armadillo-derived lepromin under identical conditions. The most striking difference between the AFB in the test sera and that in the armadillo-derived lepromin was the absence of any transverse band in the former. This suggested that the AFB in the patients' circulation were not in division stage. Furthermore, electron-dense material were deposited on the AFB co-precipitated from the patients' sera, which were not found on the AFB co-precipitated from the armadillo-derived lepromin.

Adult↗

PubMed1994

T cell reactivity against antigen 85 but not against the 18- and 65-kD heat shock proteins in the early stages of acquired immunity against Mycobacterium leprae.

T cell proliferation and interferon-gamma (IFN-gamma) production of peripheral blood mononuclear cells (PBMC) from 20 household contacts were tested against the 18- and 65-kD heat shock proteins from Mycobacterium leprae (ML18 and ML65 respectively) and antigen 85 from Myco. bovis bacille Calmette-Guérin (BCG) (Ag 85) during a 12-months follow-up study. Among the eight contacts that became positive, eight showed positive reactivity against Ag 85, 5/8 against ML65 and 4/8 against ML18 at the end of the study. Of the 16 contacts who were lepromin-positive either at first or second testing, all responded to Ag 85, 11 to ML 65, but only eight reacted to ML18 antigen. Contacts who were lepromin-positive at first testing developed responses to ML18 only at second testing. In contrast, among the four contacts that remained lepromin-negative during the follow up, three proliferated to Ag 85 either at first or second testing, but only one produced IFN-gamma against Ag 85 at the end of the study. These results demonstrated that T cell reactivity and particularly IFN-gamma secretion against Ag 85, but not against ML18 and ML65, might be a predominant mechanism in the early stages of acquired protective immunity against Myco. leprae.

Adolescent↗

PubMed1994

T lymphocyte reactivity of leprosy patients and healthy contacts from a leprosy-endemic population to delipidified cell components of Mycobacterium leprae.

In this study, we measured in vitro proliferative responses of peripheral blood mononuclear cells from both leprosy patients across the clinical spectrum and also healthy contacts from a leprosy-endemic population to delipidified cell components of Mycobacterium leprae (DCC) and Dharmendra lepromin. Dharmendra lepromin was poor in inducing in vitro T cell proliferation in all the study groups, even though it elicited marked in vivo skin test reaction in tuberculoid leprosy patients and healthy contacts. In contrast, Dharmendra preparation of BCG induced marked T-cell response in tuberculoid as well as bacterial index negative lepromatous patients. DCC induced a significantly higher lymphoproliferative response than Dharmendra lepromin in all study groups. A significant positive correlation was observed between the lymphoproliferative responses to DCC and BCG. The present study, based on a large number of leprosy patients and healthy contacts, clearly demonstrates that DCC, depleted of glycolipids and lipopolysaccharides, is a good antigenic preparation for evaluating T-cell reactivity to M. leprae.

Adolescent↗

PubMed1991

Blastogenic response with autologous plasma and Mitsuda's reaction in leprosy patients and their unaffected sibs.

Many investigators have evaluated the influence of genetic constitution on the susceptibility to leprosy in studies linked to different types of research. To determine the possible existence of a family trait linked to the lymphoproliferation and to lepromin reactivity we studied the blastogenic response to phytohaemagglutinin, lepromin and M. leprae and the Mitsuda's reaction in leprosy patients and their unaffected sibs. Sixty-eight individuals were studied, 34 were leprosy patients (17 lepromatous and 17 tuberculoid leprosy) and the remaining were their sibs previously matched by sex and age. The indices of blastogenesis and lepromin reactivity were lower in lepromatous than in tuberculoid patients, that confirmed the immunological polarity of the two types of leprosy. Both the lymphoproliferation and Mitsuda's reaction results suggest different cell immune responses in leprosy patients and their unaffected sibs, so that the hypothesis of a family trait favouring the similarity of responses to these tests among sibs becomes unlikely.

Antigens, Bacterial↗

PubMed1989

Evaluation of humoral immunity on leprosy patients in Taiwan: a preliminary report.

Twenty-four tuberculoid (T)-type and 31 lepromatous (L)-type leprosy patients from Taiwan Provincial Lo-Sheng Leprosarium were enrolled in this study. Twenty-six age- and sex- matched normal subjects were also studied as a control group. The evaluation of their general and specific humoral immunity included B-cell subpopulations, 3 major classes of immunoglobulin (G, A and M) and antibodies in the IgG class against lepromin suspension and Bacillus Calmette-Guerin (BCG) sonicate. T-type patients showed a larger B-cell percentage than L-type patients (p less than 0.01). In general, patients with leprosy, both T and L types, had higher serum immunoglobulin levels than the control group. T-type patients showed greater antibody levels than the control group (p less than 0.05 for anti-lepromin and p less than 0.0001 for anti-BCG). L-type patients demonstrated a higher anti-BCG IgG level than the control group (p less than 0.0001). The level of anti-BCG IgG was more frequently above the cutoff level than that of anti-lepromin IgG in leprosy patients (p less than 0.01 for T, p less than 0.005 for L). In conclusion, humoral immunity is not impaired in leprosy patients. Discrepancies for T- and L-type patients among B-cell subpopulation, serum immunoglobulin levels and specific antibody levels reflect different aspects of cell-mediated immunity impairment. Though leprosy patients had elevated anti-BCG IgG levels, it is impossible to differentiate L- and T-type patients; specific antigens are needed for serodiagnosis of leprosy patients in Taiwan.

Adult↗

PubMed1989

Detection of subclinical infection in leprosy: an 8 years follow-up study.

A follow-up study has been carried out using Fluorescent Leprosy Antibody Absorption (FLA-ABS) test in 1069 healthy contacts of multi and pauci-bacillary leprosy patients. Simultaneously lepromin testing with Dharmendra antigen has also been done to determine their delayed type hypersensitivity. In nearly 8 years of follow-up, 46 contacts have developed disease and of these 41 contacts were FLA-ABS positive and lepromin negative. It is inferred that test (along with lepromin) can be used to identify the contacts who are at higher risk of developing the disease. FLA-ABS test has also been found to be highly sensitive for detection of subclinical infection specially in younger age groups. This test could therefore serve as a very sensitive epidemiological tool for assessing the extent of disease in the community and for monitoring the transmission of disease especially after MDT and other intervention measures.

Adolescent↗

PubMed1987

Effects of ICRC antileprosy vaccine in healthy subjects.

Long-term effects of the administration of the ICRC antileprosy vaccine in healthy subjects have been investigated both in household contacts of leprosy patients and noncontacts in a general population. Each volunteer received a dose of vaccine containing either 0.5 x 10(9) or 1.7 x 10(7) bacilli intradermally. The vaccine induces a dose-dependent lepromin conversion in negative subjects at 8 weeks after vaccination. One year later, the conversion rates are more than 90% in both high- and low-dose groups. Lepromin conversion is stable for at least 3 years. When administered to the lepromin-positive contacts, the vaccine induces a statistically significant increase in intensity of the reaction at 6 months. During the 3-year observation period, the subjects have remained healthy and no untoward effects, including any neurological lesions, have been observed. There has also been no change in the circulating level of antibodies against the phenolic glycolipid-I antigen of Mycobacterium leprae as a result of vaccination. The vaccine thus induces not only stable immunity but is safe and, being given as a single injection, has a high acceptability. Its field trials will begin soon.

Adolescent↗

PubMedDate not supplied

[Cell mediated immunity in a group of lepers (leukocytes migration inhibition test)].

Ten lepers with the lepromin-negative lepromatous form and ten lepers with the lepromin-positive tuberculoid form who underwent the leukocyte migration inhibition test were studied. A market impairment of cell-mediated immunity in the lepromatous group as well as significative differences of the average inhibition rates between both groups of patients were found. Results from this in vitro test were correlated to those from the lepromin skin test and a correspondence in 18 out of the 20 patients studied was obtained.

Cell Migration Inhibition↗

PubMedDate not supplied

Immuno-stimulatory effect of levamisole in borderline leprosy cases.

Eleven cases of borderline-borderline leprosy were subjected to levamisole therapy for 3 months. Levamisole was given 150 mg/day on three consecutive days every fortnight along with dapsone (DDS). Immuno-stimulation was assessed by lepromin test using Lepromin-A supplied by W.H.O. containing 4.0 X 10(7) bacilli per milli litre. It was found that there was statistically significant change in lepromin reaction after levamisole therapy.

Adjuvants, Immunologic↗