The functional state of the complement system in leprosy

Ninety-one patients with different clinical forms of leprosy, 36 lepromatous (LL), 33 tuberculoid (TL), and 22 dimorphic (DL), and 31 healthy volunteer donors were included in this study. Total complement system (CS) activity was assessed by hemolytic methods, whereas individual components were quantified by the enzyme-linked immunosorbent assay. Under conditions allowing initiation of cascade by the classic pathway (CP) but not alternative pathway (AP) activation, significant CS consumption was detected only in sera from patients with LL. In this group of patients, C4 but not factor B (fB) or C3 was significantly reduced, whereas mannose-binding lectin (MBL) serum levels were significantly higher. These results indicate that the CP is involved in CS activation in patients infected with Mycobacterium leprae manifesting LL clinical form of leprosy. An association is likely between circulating immune complexes and MBL high serum levels for initiation of CS activation in patients with LL form of leprosy.

Serum adenosine deaminase levels in reactional and non-reactional leprosy

BACKGROUND AND AIMS

Altered serum adenosine deaminase (ADA) levels have been recorded in various diseases involving lymphocytes and/or lymphoreticular system including leprosy. The study was planned to evaluate alterations in serum ADA levels, if any, in reactional and non-reactional leprosy.

METHODS

Eighty patients of leprosy, comprising 60 patients of non-reactional leprosy and 20 patients of reactional leprosy were studied along with 20 normal healthy controls. Five milliliters of venous blood was collected and ADA levels were estimated by the method of Giusti (1974).

RESULTS

There were 54 males and 26 females. The age of the patients ranged from 5 years to 62 years. The duration of leprosy ranged from 15 days to 3 years. The mean serum ADA level in normal controls was 10.31 +/- 0.58 u/L. The serum ADA levels were raised in leprosy patients, significantly so in multibacillary patients. The serum ADA levels were higher in patients of leprosy with reaction.

CONCLUSIONS

The study showed significantly high serum ADA levels in multibacillary leprosy and this was further increased in patients of leprosy with reaction. This may be because of increased lymphoreticular activity during the reactional phases.

Adrenocortical hormones and interleukin patterns in leprosy

The functional status of adrenocortical hormones and their relationship to the pattern of inflammatory cytokines in the lepromatous and tuberculoid poles of leprosy were investigated. Interleukin (IL)-1beta, IL-6 and tumour necrosis factor (TNF)-alpha plasma levels, C-reactive protein (CRP) concentrations and erythrocyte sedimentation rates (ESR) were significantly higher in LL/BL (lepromatous) leprosy patients than in control subjects. There was a significant positive correlation between IL-6 and TNF-alpha plasma levels and ESR and CRP concentrations. IL-1beta was positively correlated with ESR but not with CRP. Both baseline and stimulated adrenocorticotropic hormone and cortisol plasma levels were not different between patients and control subjects. In contrast, adrenal androgen dehydroepiandrosterone sulphate (DHEA-S) plasma levels were significantly lower in leprosy patients than in sex-matched control subjects. There was a significant inverse correlation between DHEA-S and IL-6, TNF-alpha, and CRP concentrations. This finding may be of pathogenetic significance in this disease and in other inflammatory states.

Markers of platelet, endothelial cell and blood coagulation activation in leprosy patients with antiphospholipid antibodies

OBJECTIVE

To evaluate plasma levels of markers of platelet, endothelial cell and blood coagulation activation in leprosy patients with or without antiphospholipid antibodies (aPL) and to compare them to those found in patients with antiphospholipid syndrome (APS).

METHODS

42 patients with leprosy (35 lepromatous and 7 borderline): 29 aPL(+) and 13 aPL(-), as well as 26 healthy subjects as normal controls (NC) and 79 control aPL patients without leprosy (59 with and 20 without APS) were included in the study. Plasma soluble P and E selectin (sPsel and sEsel), and VCAM-1 (sVCAM-1), prothrombin F1 + 2 fragment (F1 + 2), thrombin-antithrombin complexes (TAT) and D dimer (DD) were measured by ELISA. The protein C pathway was assessed by the ProC global test.

RESULTS

Leprosy patients with aPL presented increased median levels of sPsel [ng/ml (82.0 vs 36.0, p < 0.001)] and sVCAM-1 [ng/ml (495 vs 335, p < 0.001)] compared to NC, as observed in control aPL patients without leprosy. Levels of sPsel in aPL(+) patients with leprosy were significantly higher than in aPL(-) ones (52.5 ng/ml), p = 0.005. However, plasma markers of thrombin generation were increased in control aPL patients without leprosy but not in those with leprosy. ProcC global test was abnormal in 24.1% of leprosy patients with aPL compared to 4.4% of NC (p < 0.024), and to 57.2% of control patients with aPL without leprosy (p = 0.005).

CONCLUSIONS

We demonstrated that although patients with leprosy present a high prevalence of aPL, and platelet and endothelial cell activation in vivo to the same extent than patients with APS, they do not show a procoagulant state.

Production of transforming growth factor-beta 1 (TGF-beta1) by blood monocytes from patients with different clinical forms of leprosy

In the present study, the concentration of TGF-beta1 secreted by adherent cells isolated from human peripheral blood mononuclear cells (PBMC) and either stimulated with PGL-1 or lipopolysaccharide (LPS) or left unstimulated was determined by ELISA. The cells were isolated from untreated patients with different clinical forms of leprosy and healthy individuals. The adherent cells exhibited spontaneous release of TGF-beta1 in all clinical forms of leprosy and in healthy individuals; however, lepromatous leprosy/borderline leprosy (LL/BL) patients presenting erythema nodosum leprosum (ENL) displayed significantly higher concentrations of TGF-beta1 than either the other patients studied or the controls. These high TGF-beta1 levels were consistently observed when LL/BL ENL cells were stimulated with phenolic glycolipid (PGL-1) or LPS, and even in the absence of a stimulus (P < 0.01). The most significant differences in TGF-beta1 levels were observed when comparing the results in the presence of PGL-1 from ENL with, in order of significance: tuberculoid leprosy (TT) patients (P < 0.001), LL/BL patients without ENL (P < 0.01), healthy individuals (P < 0.01) and borderline-borderline/borderline-tuberculoid (BB/BT) patients with reversal reaction (RR) (P < 0.01). The BB/BT patients produced equivalent levels of TGF-beta1 compared with LL/BL patients without ENL, for all types of stimuli (P > 0.05). In contrast, TT patients produced the lowest levels of TGF-beta1 among all the subjects studied (both patients and healthy controls), especially following PGL-1 stimulation (P < 0.001, and P < 0.05, respectively). In conjunction with our previous data regarding TGF-beta1 expression in dermal lesions, it appears that TGF-beta1 probably plays different roles in leprosy: (i) to mediate a suppressive action locally, associated with the presence of PGL-1, and (ii) to induce proinflammatory effects when secreted systemically by monocytes, thereby acting as a modulatory cytokine in the acute inflammatory reactions of ENL and associated with the Th2 immune response in multibacillary forms of leprosy.

Determination of circulating IgG subclasses against lipoarabinomannan in the leprosy spectrum and reactions

IgG subclasses against lipoarabinomannan of mycobacteria were analyzed in the sera of leprosy patients. Patients with active leprosy [tuberculoid and lepromatous, patients undergoing erythema nodosum leprosum (ENL) and reversal reactions] and inactive cases (tuberculoid and lepromatous who were cured after chemotherapy) were included in this study. Active lepromatous patients had higher levels of IgG subclasses, except IgG4, compared to active tuberculoid patients. Some of the inactive cases (lepromatous patients cured after chemotherapy) were positive for the IgG1, IgG2 and IgG3 subclasses. However, their levels are lower than active lepromatous cases. On the other hand, no difference in the subclass levels between the active and inactive tuberculoid groups could be observed. While a significant fall in the level of IgG3 in ENL was observed as compared to lepromatous leprosy without ENL, higher levels of IgG1 and IgG2 were found in patients with reversal reactions compared to their active counterparts without reactions.

beta 2-Glycoprotein I-dependence of anticardiolipin antibodies in multibacillary leprosy patients

This study was undertaken to investigate the influence of beta 2-glycoprotein I (GPI) on anticardiolipin antibody (aCL) titration in leprosy. The study group consisted of 140 sera from patients with multibacillary leprosy (46 borderline, 94 lepromatous). The group included newly diagnosed, previously untreated patients, patients under treatment and patients released from treatment. GPI addition enhanced significantly the aCL titres in sera from lepromatous leprosy but not in those from borderline leprosy. Moreover, when the patients were classified according to their bacteriological status, aCL titres were found to be significantly higher in skin smear positive patients compared to bacteriologically negative patients. Thus, the present study demonstrates that aCL in multibacillary leprosy patients are mainly of the GPI-dependent type and emphasizes the importance of GPI addition for aCL titration in leprosy.

Cytokines in leprosy, II. Effect of treatment on serum cytokines in leprosy

BACKGROUND

Multidrug therapy (MDT) causes a decrease in the bacterial burden in leprosy patients. Does the decrease in the antigenic stimulation of the immune system have an effect on cytokine production?

METHODS

The effect of treatment on serum cytokines was evaluated in 36 leprosy patients and 35 reactional leprosy patients and compared with that in 20 age- and sex-matched healthy individuals. The enzyme-linked immunosorbent assay (ELISA) technique was used to measure serum levels of interleukin-2 receptor (IL-2R), interleukin-10 (IL-10), and interleukin-1beta (IL-1beta) before and after treatment. These cytokines represent T-helper 1 (TH1), T-helper 2 (TH2), and macrophage cytokines, respectively.

RESULTS

The studied serum cytokines were significantly reduced after 1 year of treatment in leprosy patients. The degrees of reduction were significantly positively correlated with a reduction in the bacterial index (BI) and morphologic index (MI). After 1 year of MDT (but not 6 months), paucibacillary (PB) patients showed a significant reduction in all the studied serum cytokines to levels comparable with those of healthy controls. Multibacillary (MB) patients also showed a significant reduction in all the studied serum cytokines, but the levels were still significantly higher than those of healthy controls. Leprosy patients with high levels of serum IL-1beta were more susceptible to the development of reactions after the initiation of treatment. Corticosteroid therapy of reactional patients resulted in a significant reduction in the studied serum cytokines to levels similar or lower than those of nonreactional leprosy patients. The dose of steroids showed a significant positive correlation with the amount of decrease in IL-1beta.

CONCLUSIONS

MDT caused a reduction in serum cytokines correlated with a reduction in the bacterial burden. It is advisable to continue MDT for PB patients for 1 year. Serum IL-1beta levels may have a prognostic value for the susceptibility of leprosy patients to the development of reactions.

Cytokines in leprosy, I. Serum cytokine profile in leprosy

BACKGROUND

Leprosy is a chronic infectious disease characterized by a broad spectrum of clinical forms depending on the patient's immune response, in particular cell-mediated immune response.

METHODS

Cytokines can play a role in the cell-mediated immune response. Serum levels of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), interleukin-2 receptor (IL-2R), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) were measured by enzyme-linked immunosorbent assay (ELISA) in 55 untreated leprosy patients and 35 reactional leprosy patients, in addition to 20 age- and sex-matched healthy controls.

RESULTS

Leprosy patients showed significantly higher serum levels of the studied cytokines (except IL-2) compared with healthy controls. When the two poles were compared, tuberculoid leprosy (TT) patients showed significantly higher levels of IFN-gamma and TNF-alpha with significant negative correlations with the bacterial index (BI), whereas lepromatous leprosy (LL) patients showed significantly higher serum levels of IL-2R, IL-10, and IL-1beta with significant positive correlations with the BI. Both type I and type II reactional patients showed significantly higher serum IFN-gamma, IL-2R, and IL-1beta, in addition to IL-10 in type II reactional patients, compared with nonreactional leprosy patients. When compared with each other, type I reactional patients showed increased levels of IFN-gamma, whereas type II reactional patients showed increased levels of IL-10.

CONCLUSIONS

In leprosy patients, both IFN-gamma and TNF-alpha are immunoprotective, whereas IL-2R, IL-10, and IL-1beta are immunosuppressive. Our results indicate that type I reaction, with increased levels of IFN-gamma, is a cell-mediated immune response, whereas type II reaction, with increased levels of IL-10, is essentially an immune complex disease.

IgG antibody subclasses, tumor necrosis factor and IFN-gamma levels in patients with type II lepra reaction on thalidomide treatment

A group of 9 Mexican lepromatous leprosy patients was studied at the beginning of a type II reaction (erythema nodosum leprosum, ENL) and after 1 or 2 months of thalidomide treatment. ENL patients at the onset of the reaction had slightly higher amounts of anti-Mycobacterium leprae IgG1 and IgG2 antibodies, compared to similar lepromatous patients that did not develop ENL. Neither these antibody levels nor IgM and the other IgG subclasses were importantly modified after thalidomide treatment. Serum TNF was significantly higher in the patients that developed ENL compared to those that did not develop the reaction. TNF levels were slightly decreased after 1 month of thalidomide treatment and significantly decreased after 2 months of treatment. Serum IFN-gamma was significantly lower in patients at the onset of ENL and was increased after 1 and 2 months of thalidomide treatment.

Levels of IgG subclasses in active and inactive cases in the disease spectrum of leprosy

The present study was carried out to establish the role of IgG subclasses in leprosy. IgG subclasses to Mycobacterium leprae sonicated antigens (MLSA) and phenolic glycolipid-I (PGL-I) were determined in 124 patients with active leprosy across the disease spectrum and in 76 cases with inactive disease after completion of chemotherapy. IgG2 antibodies were found to be the predominant subclass across the disease spectrum. Lepromatous patients showed elevated levels of IgGI. IgG3 antibody levels were higher in lepromatous than that in tuberculoid patients. Patients with erythema nodosum leprosum showed a significant fall in IgG3 antibody to MLSA. While chemotherapy induced a reduction in IgG1, IgG2 and IgG3 to PGL-I in almost all types of leprous patients, for MLSA the reduction was noticed for these subclasses only in lepromatous patients. IgG4 responses to these antigens were low through out the disease spectrum and did not alter with chemotherapy.

Excretion of clofazimine in human milk in leprosy patients

Clofazimine is an important and effective constituent of multi drug therapy for leprosy. A study has been conducted to determine the distribution of clofazimine in maternal milk so that the safety of breast-feeding during maternal ingestion of the drug can be ascertained. Eight female leprosy patients (LL/BL) on clofazimine, 50 mg daily or 100 mg on alternate days for 1-18 months, (mean 5.0 +/- 1.81 months; median 3.25 months) and in the early lactating phase were studied. Blood samples and milk specimens were collected 4-6 hr after the last daily dose. Clofazimine was assayed in the milk and plasma samples by HPTLC. Mean plasma and milk clofazimine levels were 0.9 +/- 0.03 micrograms/ml and 1.33 +/- 0.09 micrograms/ml respectively. The ratio of milk to plasma drug concentration ranged from 1.0 to 1.7 with a mean of 1.48 +/- 0.08. The amount of drug ingested by the infants was 0.199 +/- 0.013 mg/kg/day which represented 22.1 +/- 1.9% of the maternal dose.

Humoral and cellular immune reactivity to recombinant M. leprae antigens in HLA-typed leprosy patients and healthy controls

In our search for Mycobacterium leprae antigens that might specifically induce immunity or immunopathology, we have tested both humoral and cellular immune reactivity against purified recombinant M. leprae antigens in 29 paucibacillary (PB), 26 multibacillary (MB) leprosy patients, and 47 matched healthy contacts. The following M. leprae antigens were tested: 2L-1 (65L-1, GroEl-1), 2L-2 (65L-2, GroEl-2), 4L (SoDA), 43L, 10L (B) and 25L (Sra). The individuals were also typed for HLAD-RB1 and DQB1 in order to see whether leprosy status and/or immune reactivity to these antigens might be associated with certain HLA types. We also tested sera from another 48 patients before, during and after multidrug therapy (MDT) to study the relationship between antibody reactivity to recombinant M. leprae antigens and MDT. Antibody titers to the four recombinant M. leprae antigens tested and to D-BSA were higher in MB patients compared to PB patients and healthy controls, and declined with treatment. From a diagnostic or monitoring point of view none of the recombinant antigens seemed to be an improvement over D-BSA, mainly due to the lower sensitivity. IgG subclasses were measured in positive sera of untreated patients. These were mainly of the IgG1 and IgG3 subclasses, but subclass diversity was also observed and antigen dependent: all four subclasses could be detected against 10L (B), only IgG1 and IgG3 against 43L and only IgG1 against 25L and 2L-1. Cellular immune reactivity against the purified recombinant M. leprae antigens was measured in a lymphocyte stimulation test (LST). As for M. leprae, there was an inverse correlation between antibody and T-cell reactivity. However, the number of LST responders to recombinant antigens was much lower than to M. leprae. The 43L antigen was recognized most often (19%-24% of individuals tested) and more often than the 10L (B) antigen (10%-12%). No clear correlation was observed with leprosy type or protection and, in general, M. leprae nonresponders were also negative with recombinant antigens. Finally, we confirmed that HLA-DRB1*02 is associated with leprosy in this population, and we observed an association between DQB1*0601 and lepromatous leprosy. The number of positive individuals was too small to allow a meaningful analysis of the relationship between HLA type and immune reactivity. Although these data do not allow a conclusion as to one of these purified recombinant antigens being either protection or disease related, the antigen-dependent IgG subclass diversity warrants further study on antigen-specific qualitative differences in immune reactivity that may be relevant for the outcome of an infection with M. leprae.

Detection of S-100 protein and anticeramide antibodies in leprosy patients by ELISA

The status of assay for S-100 antigen protein and anticeramide antibodies in serum in understanding nerve damage in different forms of leprosy were evaluated by the enzyme immunoassay. Based on the clinical and smear examination, patients were classified as indeterminate (Ind), tuberculoid (TT), borderline tuberculoid (BT), borderline lepromatous (BL) and lepromatous (LL). Antibody levels against ceramide were observed in sera of leprosy patients with 37.5% of Ind, 28% of TT, 66% BT, 78% BL and 62% LL patients positive as against 8% endemic normal sera. The mean OD ranged from 0.141 to 0.275 in different groups of leprosy. In contrast, S-100 was detected in 71.4% Ind, 88.8% TT, 76.4% BT, 100% BL and 95.8% LL, while 5% of ENL samples were positive for S-100 antigen. Mean S-100 levels in these different categories of patients were significantly higher Ind--0.45 ng/ml, TT--0.32 ng/ml, BT--0.23 ng/ml, BL--0.23 ng/ml, LL--0.19 ng/ml as compared to that of normal 0.07 ng/ml. In general S-100 seems to be a more sensitive and reliable marker than anticeramide antibodies for nerve damage. Five out of 7 indeterminate cases show increased levels of S-100, showing an extent of nerve damage similar to that of TT and could be a useful marker for assessing nerve damage in indeterminate patients for better management.

Tumor necrosis factor: status in reactions in leprosy before and after treatment

BACKGROUND

Tumor necrosis factor-alpha (TNF) is an important mediator of immunologic responses to chronic infections.

METHOD

Sera from 25 patients with acute reactions (6 with type 1 upgrading, 8 with type 1 downgrading, and 11 with type 2 reaction) were assayed for TNF before treatment and after clinical remission of the acute episode. The results were compared with serum TNF levels in healthy controls and fresh pauci- and multibacillary leprosy patients.

RESULTS

TNF levels in acute reactions were higher than in the control groups (significant only in upgrading reaction). In type 1 reaction, serum TNF concentrations fell to approximately the levels of the control patients following treatment and clinical remission. In type 2 reaction, however, levels of TNF were seen to rise further (became statistically significant) as a result of therapy induced clinical remission.

CONCLUSIONS

The rise in TNF-alpha level in reactions in leprosy is significant and indicates its active role in immunopathogenesis. The corresponding decline in TNF-alpha levels seen following regression of type 1 (lepra) reactions was not observed in the case of type 2 (ENL) reaction. This probably reflects the enhancement of cellular immunity in such cases and/or an attempt by the immunologic process to overcome specific inhibitors.

Reaction in leprosy: acute phase reactant response during and after remission

Sera from 25 patients with type 1 (Lepra), upgrading and downgrading, and type 2 (erythema nodosum leprosum [ENL]) reactions were assayed, during the reaction and after its clinical remission, for changes in levels of alpha-1-antitrypsin (A1A) and C-reactive protein (CRP). The results were compared with those from normal healthy adults and patients of leprosy without history and/or clinical evidence of reaction. The A1A levels correlated better with changes in status of type 1 reaction; whereas CRP levels correlated well with alterations in type 2 reactions and were definitely superior to A1A in this situation for monitoring the course of these episodes.

Coronary heart disease risk factors in Hansen's disease sufferers

In the frame of an epidemiologic study of Hansen's disease (HD) sufferers, several risk factors have been investigated which might explain the high prevalence of coronary heart disease (CHD) among HD patients. The data analyzed in the present study are derived from 293 HD patients (157 men and 136 women). The patients, after having completed a WHO adopted questionnaire, were given a complete physical examination, a resting and an exercise electrocardiogram, and biochemical as well as hematological examinations. Coronary HD patients, when compared to noncoronary HD patients, showed statistically significant differences in the following parameters: (1) mean age, (2) mean concentration of the electrophoretic fraction of alpha-lipoproteins, (3) deviation from mean weight, (4) prevalence of hypertension, and (5) prevalence of the borderline lepromatous form of HD. However, the differences found when comparing other parameters, such as blood pressure, smoking, diabetes mellitus, total cholesterol, triglycerides, pre-beta and beta-lipoproteins, uric acid, erythrocyte sedimentation rate, ABO blood groups, etc., did not reach the level of significance. These findings suggest that HD sufferers are a special population subgroup with reference to CHD risk factors, differing in many ways from the general population.

Serum tumor necrosis factor and interleukin 1 in leprosy and during lepra reactions

Tumor necrosis factor--alpha (TNF), one of the mediators of septic shock, has a role in the immunopathological complications of several infections. However, its role in leprosy is yet unclear. In this study, serum TNF and IL-1 levels in 64 patients spread over the spectrum of leprosy [lepromatous leprosy (LL), 30; borderline lepromatous, 12; borderline borderline, 8; and borderline tuberculoid-tuberculoid leprosy, 14] were measured at the time of admission. Elevated levels of TNF ranging from 15 to 4500 pg/ml were detected in lepromatous leprosy cases (399 +/- 189) and low levels ranging from 15 to 160 pg/ml were detected in the tuberculoid form of leprosy. Patients undergoing type 1 and type 2 lepra reactions also exhibited high TNF levels of 15-2100 pg/ml. Of the 14 clinically healthy individuals studied, 3 showed TNF levels of 15, 50, and 58 pg/ml. Interleukin 1-beta (IL-1) levels were found to be significantly higher in LL cases (70-5000 pg/ml) (328 +/- 184) in comparison to other groups or normal controls (9 +/- 3). The coefficient of correlation between TNF and IL-1 levels was statistically significant in LL and reaction cases (r = 0.96, P less than 0.001). These patients were followed up as outpatients for a period of 1 year. It was observed that 4 out of 8 patients with TNF levels greater than 100 pg/ml went into lepra reactions between 2 and 6 months after entry into the study, whereas only 5 out of 56 with less than 100 pg/ml went into mild lepra reactions (chi 2 = 9.7, P less than 0.01). Determination of TNF and IL-1 levels thus seems to have a prognostic significance in terms of lepra reaction in patients.

Correlation of serum lipids and lipoproteins in leprosy

Serum lipids and lipoproteins were assessed in sixty leprosy and forty age and sex matched healthy controls. The study subjects included cases of LL with reactions, LL without reactions, BL with reactions, BL without reactions, BT and TT types of leprosy. The levels of serum phospholipids, triglycerides, total cholesterol, LDL and VLDL fractions were significantly decreased in leprosy patients compared to control subjects. The levels of serum HDL cholesterol and HDL fraction were significantly elevated in leprosy patients. Maximum elevation in serum HDL cholesterol level and HDL fraction and maximum reduction in the levels of serum phospholipids, triglycerides, total cholesterol and LDL and VLDL fractions were observed in lepromatous leprosy (LL) patients with reactions.

Enzyme immunoassay of phagocytosis stimulating tetrapeptide "tuftsin" in normal and leprosy sera

The serum concentrations of the phagocytosis stimulating the tetrapeptide, tuftsin, were determined by competitive enzyme immunoassay in borderline tuberculoid/tuberculoid (BT/TT, 16 cases), borderline lepromatous/lepromatous (BL/LL, 16 cases), and in healthy controls (20 cases). Using checkerboard titration, 10 ng/well of diphtheria toxoid-p-aminophenylacetyl tuftsin (DTPT) conjugate when incubated with tuftsin antisera at 1:15,000 dilution with a preincubation time of 60 min with the competitor (tuftsin) followed by a further 60-min incubation onto the DTPT-coated wells gave consistent results with a sensitivity of 5 ng/well tuftsin. The mean serum tuftsin concentration was significantly lower in BL/LL patients (134.42 +/- 48.7 ng/ml, p less than 0.01) than in healthy controls (262.86 +/- 59.8 ng/ml), while BT/TT sera (210.94 +/- 75.5 ng/ml) showed slightly decreased levels than did normals, which was not statistically significant. The mean serum IgG levels in BL/LL and BT/TT patients (37.26 +/- 10.99 mg/ml; 28.08 +/- 6.57 mg/ml, respectively) showed significantly (p less than 0.001) higher concentrations than did healthy controls (12.3 +/- 3.6 mg/ml). These observations on the serum concentrations of tuftsin and IgG in leprosy individuals suggest that there is splenic dysfunction in BL/LL patients in terms of the processing of leukokinin to release the free, active molecule tuftsin.

Serum levels of tumour necrosis factor-alpha and interleukin-1 beta during leprosy reactional states

The possible role of cytokines in leprosy reactions was investigated by analysing the levels of tumour necrosis factor (TNF) and interleukin-1 (IL-1) in serum samples from 39 leprosy patients, 22 of them presenting either type I (upgrading) or type II (ENL) reactions. Fifty per cent of the patients showed elevated concentrations of TNF and IL-1 in at least one of the serum samples tested. This included all four patients undergoing type I reversal reaction and nine (50%) of the ENL patients studied. Concentrations of TNF above 1000 pg/ml were found in four patients with ENL. Development of erythema multiforme in these ENL patients represented an aggravating factor and all four patients suffering from this type of lesion demonstrated increased serum TNF levels. All BT patients tested presented elevated IL-1 levels, while only half of them presented elevated levels of TNF. No correlation was found between any particular systemic symptoms and the levels of TNF and IL-1. These results suggest that TNF and IL-1 may be implicated in leprosy reactions, either acting directly or in synergism with other cytokines.

Serum zinc/copper ratio in subtypes of leprosy and effect of oral zinc therapy on reactional states

Serum zinc and copper levels and zinc/copper ratios were studied in 86 healthy controls, 45 cases of borderline tuberculoid (BT), 31 cases of borderline lepromatous (BL), 117 cases of lepromatous (LL) leprosy patients, 16 cases with severe erythema nodosum leprosum (ENL) reaction, and 16 cases with ENL reaction receiving oral zinc therapy. A significant reduction in serum zinc levels was noticed in all types of leprosy, the maximum decrease being seen in cases with ENL reaction. Conversely, the copper levels were significantly increased from BT to LL cases with ENL reaction in a progressive manner. A very good negative correlation (r = -0.998) was noticed between mean serum zinc and copper levels from healthy controls to active LL cases with ENL reaction. After oral zinc therapy, the serum zinc levels were significantly increased in all of the 16 LL patients with ENL reaction. In contrast, the copper levels were not decreased, indicating that oral zinc therapy can restore normal zinc levels in leprosy patients but is unable to reduce the increased copper levels.

Serum tumor necrosis factor levels and disease dissemination in leprosy and leishmaniasis

It has been suggested that tumor necrosis factor alpha (TNF alpha) may serve as an important antigen-independent host defense mechanism against parasitic organisms. Sera from 66 patients with leishmaniasis and 68 patients with leprosy, all from Ethiopia, were tested for TNF alpha using an enzyme-linked immunoassay. Sera from patients with the multi-parasitic/bacillary type of disease (visceral or diffuse cutaneous leishmaniasis and lepromatous leprosy), known to be associated with absent or low specific T cell response, contained significantly higher TNF alpha titers than those of patients with pauci-parasitic/bacillary disease (localized cutaneous leishmaniasis and nonlepromatous leprosy). High titers of TNF alpha in the absence of a functioning T cell response do not appear to confer resistance against Leishmania aethiopica and Mycobacterium leprae.

Glucose tolerance test in leprosy

Glucose tolerance test was carried out in 43 cases of leprosy. They included cases of tuberculoid, borderline, lepromatous leprosy and those with lepra reaction. It was observed that normal curve was common in tuberculoid leprosy. Flat glucose tolerance curve was observed in borderline and lepromatous leprosy. However, the diabetic curve was common in Lepra reaction. Fasting blood sugar was low in lepromatous leprosy and it tended to be marginally high in lepra reaction. Normal GTT response was observed in those with duration of disease between 0-6 months, flat curves in those with duration of disease between 7-12 months while diabetic curve was more common in those with disease duration of more than 2 years.

Hormone profile in leprosy

Hormone profile were carried out in 35 male cases of leprosy. They were divided into tuberculoid leprosy, borderline leprosy, lepromatous leprosy and lepra reaction. Serum testosterone, follicle-stimulating hormone, Luteinizing hormone, and Oestradiol level were measured in these cases of leprosy. It was observed that serum testosterone were significantly low in lepromatous leprosy (P less than 0.001) and lepra reaction (P less than 0.01). The serum levels of follicle-stimulating hormone and luteinizing hormone were significantly high in lepromatous leprosy (P less than 0.02) and lepra reaction (P less than 0.05). Serum Oestradiol was raised in approx. 60% cases in borderline leprosy, lepromatous leprosy and lepra reaction.

Solubilization of preformed immune complexes in sera of patients with type 1 and type 2 lepra reactions

Serum complement activity in leprosy patients has been studied using solubilization of preformed immune complexes as an index. The solubilization capacity of sera from lepromatous patients with or without erythema nodosum leprosum (ENL) as well as from type 1 reactional patients was found markedly reduced as compared to controls. Solubilization did not improve at all in the ENL patients after remission of the reaction phase. The addition of fresh normal sera failed to bring about any significant restoration of solubilizing capacity of the deficient sera. Mycobacterium leprae sonicate significantly reduced the solubilization capacity. Our results suggest that circulating mycobacterial breakdown products possibly interfered with the capacity of the ENL patients' sera to solubilize immune complexes.