Trichinella-induced immunomodulation: Another tale of helminth success

Trichinella spiralis is a unique parasite in that both the adults and larvae survive in two different intracellular niches in the same host. The immune response, albeit intense, is highly modulated to ensure the survival of both the host and the parasite. It is skewed to T helper 2 and regulatory arms. Diverse cells from both the innate and adaptive compartments of immunity, including dendritic cells, T regulatory cells, and alternatively activated macrophages are thought to mediate such immunomodulation. The parasite has also an outstanding ability to evade the immune system by several elaborate processes. The molecules derived from the parasites including Trichinella, particularly the components of the excretory-secretory products, are being continually identified and explored for the potential of ameliorating the immunopathology in animal models of diverse inflammatory and autoimmune human diseases. Herein we discuss the various aspects of Trichinella-induced immunomodulation with a special reference to the practical implications of the immune system manipulation in alleviating or possibly curing human diseases.

IgE sensitization to Anisakis pegreffii in Italy: Comparison of two methods for the diagnosis of allergic anisakiasis

IgE sensitization to Anisakis pegreffii in Italian subjects suffering from gastro-allergic anisakiasis (GAA) (N=5), or showing chronic urticaria (CU+) after fish consumption (N=100), was investigated. A control group (N=5) was also included. IgE response was analysed by immunoblotting (WB) assay, using both excretory/secretory products (ESPs) and crude extract (CE) of A. pegreffii larvae. The results were compared with those achieved by the conventional immunological method for Anisakis allergy (ie, immunoCAP). Among the 110 subjects, 28 showed IgE positivity with both WB and iCAP methods; 13 proved IgE reactivity, in WB assay, to ESP antigens of A. pegreffii, here provisionally indicated as Ani s 1-like, Ani s 7-like, Ani s 13-like; only 15 sera have shown IgE-WB reaction to Ani s 7-like and Ani s 13-like. iCAP and WB exhibited a high concordance value (κ=1.00) when iCAP value was <0.35 (negative result) and >50.0 (positive result). In the sera samples recorded as positive to Anisakis allergy, Ani s 1-like was responsible for 46.4% of the sensitivity, while Ani s 7-like and Ani s 13-like for 100%. They could be considered as major antigens in the diagnosis of allergic anisakiasis caused by A. pegreffii.

Detection of viable but non-culturable legionella in hospital water network following monochloramine disinfection

BACKGROUND

Prevention of legionellosis remains a critical issue in healthcare settings where monochloramine (MC) disinfection was recently introduced as an alternative to chlorine dioxide in controlling Legionella spp. contamination of the hospital water network. Continuous treatments with low MC doses in some instances have induced a viable but non-culturable state (VBNC) of Legionella spp.

AIM

To investigate the occurrence of such dormant cells during a long period of continuous MC treatment.

METHODS

Between November 2010 and April 2015, 162 water and biofilm samples were collected and Legionella spp. isolated in accordance with standard procedures. In sampling sites where MC was <1.5mg/L, VBNC cells were investigated by ethidium monoazide bromide (EMA)-real-time polymerase chain reaction (qPCR) and 'resuscitation' test into Acanthamoeba polyphaga CCAP 1501/18. According to the Health Protection Agency protocol, free-living protozoa were researched in 60 five-litre water samples.

FINDINGS

In all, 136 out of 156 (87.2%) of the samples taken from sites previously positive for L. pneumophila ST269 were negative by culture, but only 47 (34.5%) negative by qPCR. Although no positive results were obtained by EMA-qPCR, four out of 22 samples associated with MC concentration of 1.3 ± 0.5mg/L showed VBNC legionella resuscitation. The presence of the amoeba A. polyphaga in the hospital water network was demonstrated.

CONCLUSION

Our study is the first report evidencing the emergence of VNBC legionella during a long period of continuous MC treatment of a hospital water network, highlighting the importance of keeping an appropriate and uninterrupted MC dosage to ensure the control of legionella colonization in hospital water supplies.

T-cell clones in human trichinellosis: Evidence for a mixed Th1/Th2 response

In humans, studies on the cellular immune response against Trichinella are scarce. Aim of this study was to characterize the cytokine profile of T cells specific for Trichinella britovi in trichinellosis patients. Peripheral blood mononuclear cells (PBMC) were obtained from five patients involved in a trichinellosis outbreak caused by T. britovi, which occurred in 2013 in Tuscany (Italy). All the patients resulted positive for Trichinella-specific IgG, IgE and presented eosinophilia. T cells were investigated for their proliferation to excretory/secretory antigens from Trichinella spiralis muscle larvae (TsES) and for their cytokine profile. A total of 284 CD4+ and 42 CD8+ T-cell clones were obtained from the TsES-specific T-cell lines from PBMC. All T-cell clones proliferated in response to mitogen. Of the 284 CD4+ T-cell clones generated from TsES-specific T-cell lines, 135 (47%) proliferated significantly to TsES; 26% CD8+ T-cell clones showed proliferation to TsES. In the series of the 135 TsES-specific CD4+ clones, 51% expressed a Th2 profile, 30% a Th0 and 19% Th1. In the series of the 11 TsES-specific CD8+ T-cell clones, 18% were Tc2, 45% Tc0 and 36% Tc1. In human trichinellosis, the cellular immune response is, during the chronic phase, mixed Th1/Th2.

Matrix metalloproteinase (MMP)-9: A realiable marker for inflammation in early human trichinellosis

Matrix Metalloproteinases (MMPs) are involved in many physiological and pathological processes. As regards parasitic infections, the role of these proteins has been particularly studied in malaria, neurocysticercosis and angiostrongyloidosis. Recently, we evaluated serum levels of MMP-9 and -2 (gelatinases) in mice experimentally infected with Trichinella spiralis or Trichinella pseudospiralis, which cause different degrees of myositis and we found their significant increase in the former and, at a lesser extent, in the latter, thus suggesting the possibility that these gelatinases, particularly MMP-9, represent a marker of inflammation. Our aim was to evaluate the levels of MMP-9 and 2 in trichinellosis patients, to assess their possible clinical significance. Serum samples from 31 Trichinella britovi-infected individuals (20 males and 11 females), living in Tuscany, Central Italy, were analysed for MMP-9 and MMP-2 serum levels. Patients acquired infection with Trichinella after consuming raw or undercooked meat of wild boar. Their median age was 49±0.33years (range from 7 to 91). Sera was collected before starting anti-inflammatory treatment, aliquoted and stored at -20°C until use. Sera from healthy subjects was considered as controls. The gelatinolytic activity of MMPs was analysed by gelatin zymography on 8% polyacrylamide-SDS gels containing 0.1% porcine gelatin, under non-reducing conditions. Clear bands corresponding to the digested areas were evaluated with an appropriate software. MMP-9 levels were additionally determined in 15 patients using a commercial ELISA kit for human MMP-9. The zymographic analysis of the gels showed the presence in serum samples of gelatinase bands at approximately 125-kDa, 92-kDa and 72-kDa, corresponding to the MMP-9/Neutrophil gelatinase-associated lipocalin (NGAL) complex and proenzyme forms of MMP-9 and MMP-2, respectively. A significant (p<0.01) increase in gelatinolytic activity in patients compared to the control group was observed for pro-MMP-9 in 25 out of 31. The mean increase in activity was 39.25%±16.67%. No significant differences were observed for pro-MMP-2 activity. The MMP-9 levels detected by ELISA showed significant correlation with zymographic data (r²=0.62, p<0.003) and were higher in more affected patients (suffering diarrhea, facial edemas and myalgia). In conclusion, MMP-9 might be considered as a marker of inflammation in T. britovi patients. On the contrary, MMP-2 did not result significantly different in patients, compared to controls.

Laparoscopic peritoneal lavage for perforated colonic diverticulitis: a definitive treatment? Retrospective analysis of 63 cases

BACKGROUND

The ideal treatment of perforated diverticulitis and the indications for elective colon resection remain controversial. Considering the significant morbidity and mortality rates related to traditional resection, efforts have been made to reduce the invasiveness of surgery in recent decades. Laparoscopic peritoneal lavage has emerged as an effective alternative option. We retrospectively investigated the effectiveness of laparoscopic peritoneal lavage for perforated diverticulitis and the possibility that it could be a definitive treatment.

METHODS

We included patients treated with laparoscopic peritoneal lavage for perforated diverticulitis. The inclusion criteria were all emergency patients with generalized peritonitis due to Hinchey III perforated diverticulitis and some cases of Hinchey II and IV.

RESULTS

Sixty-three patients were treated with laparoscopic peritoneal lavage. Six patients (9.5 %) had Hinchey II diverticulitis; 54 patients (85.7 %) had Hinchey III; and three patients (4.8 %) had Hinchey IV. The mean operative time was 87.3 min (±25.4 min), and the overall morbidity rate was 14.3 %. One patient died because of pulmonary embolism, and there were six early reinterventions because of treatment failure. Delayed colon resection was performed in four of the remaining 57 patients (7 %) because of recurrent diverticulitis. In the other 53 patients (93 %), we saw no recurrence of diverticulitis and no intervention was performed after a median follow-up period of 54 months (interquartile range 27-98 months).

CONCLUSIONS

Laparoscopic peritoneal lavage for perforated diverticulitis can be considered a safe and effective alternative to traditional surgical resection, and using this approach, most elective colon resection might be avoided.

Neurocysticercosis in Europe: Still a public health concern not only for imported cases

Neurocysticercosis (NCC), a parasitic disease caused by the larvae of the cestode Taenia solium, is the most frequent parasitic disease of the central nervous system (CNS) in the world and the leading cause of secondary epilepsy in Central and South America, East and South Asia, and sub-Saharan Africa. It is endemic in many low- and middle-income countries of the world. Due to increased travels and immigration, NCC may be diagnosed also in non-endemic areas. In fact, tapeworm carriers from endemic zones can transmit infection to other citizens or arrive already suffering NCC. This phenomenon, occurred first in USA during the last 30 years, has been also observed in Europe, as well as in Australia, Canada, Israel, Japan and Muslim countries of the Arab World. Actually, concerning Europe, although, in some areas only few cases have been described, nevertheless the prevalence of NCC may be considered increasing, especially in Spain and Portugal. We reviewed the literature on the burden of NCC in Europe, by a search of PubMed regarding papers from 1970 to present. We only considered on PubMed published and available papers in English, French, Italian, and Spanish, the languages understood by the authors. One hundred seventy six cases of NCC have been reported in seventeen European countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Netherlands, Sweden, United Kingdom, and Croatia, Norway, Switzerland). A particular epidemic situation is present in Spain and Portugal. In fact, we collected data that show, in Spain, an increasing incidence both in immigrated patients and in those which were born in certain Spanish geographical areas and, in Portugal, prevalence similar to that observed in endemic areas. Globally, it is clear that as a result of increased migrations and travels from endemic regions, NCC is becoming an emerging public health problem in high-income countries, particularly affecting communities where hygiene conditions are poor and sub-sequentially the parasite can spread from human to human through eggs even in absence of a travel to the tropics. NCC is a preventable disease, it derives that it's important to acquire a great consciousness of the epidemiology and to implement accurate surveillance systems.

Hepatitis C is Associated with High Levels of Circulating N-Terminal Pro-Brain Natriuretic Peptide and Interleukin-6

To our knowledge, no study has evaluated N-terminal pro-brain natriuretic peptide (NTproBNP) together with interleukin-6 (IL-6) and interferon (IFN)-gamma serum levels in a large series of patients with hepatitis C virus (HCV) as possible markers of cardiac dysfunction. NTproBNP and IL-6 serum levels were valued in 55 HCV-patients, and in 55 sex- and age-matched controls. HCV-patients showed significantly higher mean NTproBNP and IL-6 levels than controls ( P = 0.001); no significant difference was observed for IFN-gamma. By defining high NTproBNP level as a value higher than 300 pg/mL (that is used to rule out heart failure in patients under 75 years of age), 12% (6/49) of HCV-patients and 0 of controls had NTproBNP (χ2; P = 0.012). In conclusion, this study demonstrates high levels of circulating NTproBNP and IL-6 in HCV-patients. The increase of NTproBNP may indicate the presence of a subclinical cardiac dysfunction. Further prospective studies quantifying symptoms and correlating these with echocardiography parameters are needed to confirm this association.

Stimulation of TH1 Response by Helicobacter Pylori Neutrophil Activating Protein Decreases the Protective Role of IgE and Eosinophils in Experimental Trichinellosis

Th2 responses seem to play an important role in defence against Trichinella spiralis (Ts). The Neutrophil Activating Protein of Helicobacter pylori (HP-NAP), that induces IL-12, and IL-23 expression and shifts to Th1 allergen-specific Th2 cells in vitro was used as an anti-Th2 agent in BALB/c mice infected with T. spiralis. The muscle larvae (ML) burden was lower ( p < 0.02) in untreated infected animals than those infected treated with HP-NAP. In both groups there was an inverse relationship between ML burden of each animal and total IgE level (controls: r −0.617, p = 0.0013 and HP-NAP-treated: r −0.678, P = 0.0001) or eosinophil count, evaluated in the same mouse on day 42 (r −0.390, P = 0.0592 and r −0.803, P = 0.0001, respectively). Inflammatory response around the nurse cell-parasite complex was significantly higher in HP-NAP-treated infected animals than in those untreated infected, on the contrary the number of eosinophils, counted around each complex was significantly lower in the first animal group. This study provides evidence of a powerful anti-Th2 activity in vivo by HP-NAP and for the partial protective effect of Th2 responses in T. spiralis infection.

Evaluation of inflammatory responses against muscle larvae of different Trichinella species by an image analysis system

The aim of this study was to evaluate the inflammatory response in the muscle tissue against Trichinella larvae of encapsulated (T. spiralis, T. britovi) and non-encapsulated (T. pseudospiralis) species. The inflammatory response was estimated in histological sections of muscle tissues from Trichinella-infected CD1 mice by a newly developed method. Nuclei were stained with one fluorescent probe, which binds nucleic acids with high affinity, and fluorescence was analysed by a software program. Evaluation of the relative fluorescence units was performed in both peri-capsular (close to the nurse cell-parasite complex) and extra-capsular (where the parasite was not visible) areas. The increase in the number of nuclei in the muscle tissues of Trichinella-infected mice was considered an inflammation marker, since uninfected muscles show low nucleus density. In order to evaluate differences in the nitrosylation pattern between encapsulated (T. spiralis, T. britovi) and non-encapsulated (T. pseudospiralis, Trichinella papuae, Trichinella zimbabwensis) species, L(1) larvae were tested by immunoblotting with an anti-nitrotyrosine polyclonal antibody. Inflammation induced by T. spiralis larvae in muscle tissues is statistically higher than that elicited by the other species, both in peri- and extra-capsular areas. Nitrosylation occurs at a higher level in encapsulated than in non-encapsulated species. The method developed in this work allows demonstration of differences in the host inflammatory response against encapsulated and non-encapsulated Trichinella species.

Specific IgG4 response directed against the 45-kDa glycoprotein in trichinellosis: a re-evaluation of patients 15 years after infection

The aim of this study was to evaluate the humoral immune response in late human trichinellosis with particular attention to the presence of IgG4 antibodies directed against the Trichinella-45-kDa glycoprotein (gp). This study re-evaluates subjects 15 years after they were involved in a trichinellosis outbreak that occurred in Central Italy following the consumption of raw boar meat infected with Trichinella britovi. The results show that ELISA tests using the E/S antigen identified five IgM- and eight IgG-positive patients and no IgA-positive patients. Tests using immunoblot (IB) with E/S antigens identified three IgM-, five IgA-, seven- IgG1- and three IgG4-positive sera. When the purified 45-kDa gp was used as an antigen, the IB revealed that six of the ten sera tested were positive for IgG4. Sera were also evaluated with a commercial kit, revealing that 11 of 12 patients had a highly sensitive reactivity against Trichinella proteins (64 and 44-43 kDa). In conclusion, humoral immune response against Trichinella is still present in these patients 15 years after the initial infection, including an IgG4 response directed to the 45-kDa gp.

Heart- and skeletal muscle-specific antigens recognized by trichinellosis patient sera

The heart can be seriously affected in human trichinellosis, and cardiac involvement can cause death. Experimental infections in rats have suggested the possible participation of immunopathological processes. The aim of the present paper was to investigate the possible presence in trichinellosis patient sera of antibodies recognizing host tissues and particularly the myocardium. Nineteen sera from late period trichinellosis patients, who acquired infection in the Poznan region (Poland), were tested by immunoblot on extracts from normal rat or human heart ventricle wall, spleen, placenta, kidney and skeletal muscle. Patients' sera recognized several antigens that were not recognized by normal sera. On rat and human heart ventricle wall, a high proportion of sera (42%) reacted with a protein of 68 kDa (P < 0.05 compared to normal sera). The reactivity with this antigen, however, was not significantly different in patients with or without cardiac involvement. When sera were tested on skeletal muscle we found that 47% reacted with a protein of 27 kDa and 53% reacted with a protein of 41 kDa (P < 0.05 for both proteins, compared with normal sera). The reactivity against the 68 kDa antigen and against the 27 and 41 kDa skeletal muscle antigens was not observed on kidney, placenta and spleen extracts. Moreover, very few bands were observed on these tissues as compared to heart and skeletal muscle tissues, thus suggesting a high tissue specificity of the reactivity of trichinellosis sera. In conclusion, this study identifies organ-specific autoantibodies in trichinellosis patient sera, their role in the pathogenesis of cardiac involvement being still unclear.

Neurocysticercosis: surgical treatment of an autochthonous case in a non-endemic region

OBJECTIVE AND IMPORTANCE

This study describes a case of autochthonous neurocysticercosis in a non endemic region where a differential diagnosis with more frequent single parenchymal lesions must be carried out.

CLINICAL PRESENTATION

The patient presenting generalized seizures and coma status under the suspicion of cerebral neoplasia was admitted to the neurosurgery division. MRI showed the presence of an ovoidal cystic lesion in right-frontotemporal region.

INTERVENTION

After right fronto-temporal osteoplastic bone flap elevation and usual dural tacking and opening, trans-scissural subaracnoid access was made possible by microsurgical strumentation in right Sylvian fissure. A cystic, translucid lesion was identified in the deep Sylvian fissure, involving the distal segment of the fissure and the frontal lobe, the cystic lesion was removed surgically. Pathological examination showed a typical picture of neurocysticercosis.

CONCLUSIONS

After both surgical and chemotherapeutic treatment with albendazole the outcome was successful. The diagnosis of neurocysticercosis should be taken into account in the presence of generalized seizures possibly due to single parenchymal lesions, even in non-endemic regions for this parasitic infection.

Cystic echinococcosis: progress and limits in epidemiology and immunodiagnosis

This study discusses the epidemiology and immunodiagnosis of cystic echinococcosis (caused by Echinococcus granulosus). Despite the development of molecular methods to prepare antigens, nowadays there is no standard, highly sensitive, and specific test available for antibody detection in cystic echinococcosis. Furthermore, because serological tests can give only a limited support to clinical findings there is a clear need for new advances in immunodiagnosis of E. granulosus infection.

Screening of an Echinococcus granulosus cDNA library with IgG4 from patients with cystic echinococcosis identifies a new tegumental protein involved in the immune escape

The worldwide problem of chronic Echinococcus granulosus disease calls for new parasite-derived immunomodulatory molecules. By screening an E. granulosus cDNA library with IgG4 from patients with active cystic echinococcosis, we identified a cDNA that encodes a predicted partial protein that immunofluorescence studies localized in the protoscolex tegument and on the germinal layer of cyst wall. We named this protein EgTeg because the 105 amino acid sequence scored highest against a family of Schistosoma tegumental proteins. Evaluating the role of EgTeg in the human early inflammatory response we found that EgTeg significantly inhibited polymorphonuclear cell (PMN) chemotaxis. Cytometric analysis of intracellular cytokines disclosed a significantly higher percentage of cells producing IL-4 than IFN-gamma (P = 0.001, Student's t-test) in T lymphocytes from patients with cystic echinococcosis stimulated with EgTeg. EgTeg induced weak Th1-dependent proliferation in 42% of patients' peripheral blood mononuclear cells. In immunoblotting (IB) analysis of total IgG and IgG subclass responses to EgTeg in patients with cystic echinococcosis, patients with other parasitoses, patients with cystic lesions and healthy controls, total IgG specific to EgTeg yielded high sensitivity (73%) but low specificity (44%) precluding its use in immunodiagnosis. Conversely, IgG4 specific to EgTeg gave acceptable sensitivity (65%) and high specificity (89%) suggesting its use in immunodiagnosis to confirm ultrasound documented cysts suggestive of E. granulosus. Because the new tegumental antigen EgTeg inhibits chemotaxis, induces IL-4-positive T lymphocytes and noncomplement fixing antibodies (IgG4) it is an immunomodulatory molecule associated with chronic infection.

Re-evaluation of patients involved in a trichinellosis outbreak caused by Trichinella britovi 15 years after infection

This study re-evaluates 13 out of 48 subjects involved in a trichinellosis outbreak that occurred in Central Italy (Umbria Region) in 1988 resulting from the consumption of raw boar meat harboring Trichinella britovi. During the outbreak, 28 of 48 serologically positive subjects were asymptomatic, whereas 20 subjects presented one or more clinical signs including but not limited to fever, myalgia, periorbital oedema and conjunctivitis. Several patients were hospitalized with severe clinical signs requiring treatment with mebendazole and corticosteroids. Upon re-evaluation of 13 patients, none presented clinical signs; however, three still had increased CPK or LDH serum levels with some signs of electromyographic changes. In this study, enzyme immunoassays (EIA) were used to test the 13 positive sera for reactivity with T. britovi antigens using both excretory/secretory (E/S) antigens and a synthetic antigen composed of beta-tyvelose conjugated to bovine serum albumin. Western blots (WB) were also carried out using a commercial kit. Studies using EIA with E/S antigen identified five positive sera; however, using beta-tyvelose as antigen, only one positive sample was identified. Nearly all sera reacted positively with one or more Trichinella antigens when analyzed by WB, in particular to the 45 k Da beta-tyvelose containing glycoprotein. Results indicate that T. britovi, though less pathogenic than other Trichinella species, is clearly capable of inducing sustainable sequelae.

Persistence of reactivity against the 45 k Da glycoprotein in late trichinellosis patients

Over the years, the opinions of clinicians on the existence of the so-called chronic trichinellosis or late sequelae of infection have differed. However, the persistence of a humoral immune response against Trichinella in these late-stage patients has been confirmed using specific tests such as the competitive inhibition assay (CIA). We evaluated sera from late-stage trichinellosis patients (2--8 years from acute infection), for their reactivity against Trichinella spiralis antigens. The following tests were carried out: (i) indirect immunofluorescence assay (IFA), performed on muscle sections from mice, 30 days following synchronous infection by intramuscular injection with T. spiralis newborn larvae (NBL); (ii) enzyme immunoassay, employing a synthetic beta-tyvelose antigen conjugated to bovine serum albumin (BSA-Ag); and (iii) western blot (WB) with both an "in house" kit and a commercial kit. The results of IFA obtained by confocal laser microscopy showed that sera reacted against both surface and internal structures of L(1) larvae but at varying levels. Employing the synthetic antigen, EIA showed that 50% of sera tested were positive for the presence of specific antibodies against beta-tyvelose. By WB, all sera were reactive with the 45 k Da glycoprotein (45 gp). These data suggest that reactivity against the beta-tyvelosylated 45 gp persists even in very late stages of human trichinellosis.

Age, menopausal status and homocysteine levels in women around menopause

OBJECTIVE

To obtain data on the relation between age, menopause and homocysteine levels in women around menopause, we collected data for a sample of about 500 women attending a menopause clinic in Milan, Italy.

STUDY DESIGN

Eligible for the study were all women aged 45-75 years, never HRT users consecutively observed for the first time at the Menopause Center of the 1st Obstetric Gynecological Clinic of the University of Milan. Fasting blood samples for total homocysteine plasma levels were collected during the visit. Of the 490 study subjects, 107 were pre-menopausal and 383 post-menopausal.

RESULTS

In the total series, the mean homocysteine level was 8.3 micromol/L (S.D. 3.7, range 3.2-48.8). The values increased from 7.8 micromol/L in women aged <47 years to 9.0 micromol/L in those aged >59. Among pre-menopausal women the mean homocysteine level was 7.7 micromol/L compared to 8.3 micromol/L in post-menopausal women: this difference disappeared on the adjusted values. In post-menopausal women only, no clear relationship emerged between years since menopause and homocysteine levels.

CONCLUSION

In our population, age, and not menopausal status, was the main determinant of homocysteine levels in women around menopause.

International Commission on Trichinellosis: recommendations on the use of serological tests for the detection of Trichinella infection in animals and man

The use of serological tests to detect Trichinella infection in domestic and wild animals and in humans has not been standardised yet. This review provides an uniform set of recommendations for the development and use of serological tests to detect circulating antibodies in serum samples. The recommendations are based on the best scientific published information and on the unpublished data from laboratories with a great expertise in this field and represent the official position of the International Commission on Trichinellosis regarding acceptable methods and the evaluation of the sensitivity and specificity. These recommendations are subject to change as new scientific information becomes available.

[The serodiagnosis of parasitic infections]

Recently, the term of clinical immunoparasitology has been coined to indicate the application of immunological methods to the laboratory diagnosis of parasitic infections. In particular, serological diagnosis (indirect diagnosis) is useful especially in the cases of toxocarosis, trichinellosis, echinococcosis, cysticercosis, toxoplasmosis, amoebic abscess, some filariasis, visceral leishmaniasis, schistosomiasis. When possible, for infections caused by protozoa or helminths, the "gold standard" is represented by direct diagnosis performed by microscopic and/or macroscopic observation of the parasite. In any case, immunological results must be interpreted in consideration of the clinical picture of the patient and confirmed possibly by finding the parasite or its genome, even using molecular methods. Furthermore, since the presence of specific antibodies can reveal an acquired infection, but not necessarily a disease, it is particularly helpful, in addition to a qualitative evaluation, a quantitative one, by determining the serum antibody titre. After recovery, the antibody levels decrease, however, they may persist for long periods, for this reason they do not help in evaluating the treatment outcome. Interpretation of serological results may be difficult when the patients originate from areas where the suspected infection is endemic, in that case, a serum positivity could reflect an old exposition to the parasite, therefore it is not related to the present clinical status. Furthermore, serology may frequently result falsely negative in not immunocompetent subjects (organ transplanted, HIV positive individuals, premature babies, diabetics). Clinicians can interpret correctly the serological results only if the Parasitology laboratory inform them about the significant diagnostic values, the sensitivity and the specificity of the test in use. At present time, many diagnostic kits for immunoparasitology are commercially available, and industries are developing newer and newer ones (which are not always validated). In relation to this aspect, it should be helpful, for each of parasitic infection, to establish reference centers, not only to control the quality of commercial kits, but also as a reference point to those laboratories which use "in house" kits. To this regard, the recent establishment of a European Centre for Control of Infectious Diseases will help. The antigen characteristics (crude, E/S, recombinant, synthetic) for assays searching for antibodies (IHA, IFA, EIA, WB) of different classes, the controls to choose for these assays, the specimen requirements will be discussed. The recent findings on the serological diagnosis of intestinal protozoa infections, malaria, leishmaniasis, echinococcosis, cysticercosis, trichinellosis, toxocariasis, schistosomiasis, strongyloidiasis will be presented.

Effect of oral or transdermal hormone replacement therapy on homocysteine levels: a randomized clinical trial

OBJECTIVE

Aim of this randomized trial was evaluate the effect on homocysteine plasma levels of two different hormone replacement therapy (HRT) formulations in a group of late postmenopausal women.

METHODS

Eligible for this study were women: in postmenopause since 5 years or more (confirmed from FSH level > or = 40 mIU/l); with body mass index (BMI) < or = 35; without endocrine, hepatic or renal diseases; not current users of vitamin B or folic acid supplements; not users of any lipid-lowering drugs and sex steroids in the 6 months before trial entry. Group A: oral estradiol valerate 2 mg per day per oral normegestrol acetate 2.5 mg per day (n = 98) for 12 months; Group B: a weekly patch releasing estradiol (50 microg per day) per oral normegestrol acetate 2.5 mg per day (n = 101) for 12 months.

RESULTS

The mean values of the homocysteine levels in the group A and B at baseline, 3, 6 and 12 months were 7.9 and 9.1, 8.7 and 8.9, 9.3 and 10.2, 9.6 and 10.2, respectively, the differences between the two treatments were not statistically significant (time by treatment interaction, P = 0.32). Otherwise, the changes of homocysteine level at the four visits was statistically significant (P = 0.0001) in both groups. In particular, in the oral treatment group homocysteine levels increased from baseline of 10.5% at 3 months, of 17.2% after 6 months of therapy and of 21.9% at the end of the study; in the transdermal group, after a little decrease at 3 months (1.5%), the increases were of 12.1 and 12.9%, respectively.

CONCLUSIONS

This study does not show any different effect of oral and transdermal treatment with estradiol plus normegestrol acetate on homocysteine levels. Further it does not support previous suggestion of a lowering effect of HRT on plasma homocysteine.

New aspects of human trichinellosis: the impact of new Trichinella species

Trichinellosis is a re-emerging zoonosis and more clinical awareness is needed. In particular, the description of new Trichinella species such as T. papuae and T. murrelli and the occurrence of human cases caused by T pseudospiralis, until very recently thought to occur only in animals, requires changes in our handling of clinical trichinellosis, because existing knowledge is based mostly on cases due to classical T spiralis infection. The aim of the present review is to integrate the experiences derived from different outbreaks around the world, caused by different Trichinella species, in order to provide a more comprehensive approach to diagnosis and treatment.

Focus of human trichinellosis in Papua New Guinea

Human trichinellosis and teniasis (Taenia solium) are meat-borne helminthic infections with a wide distribution throughout the world. However, there is little information on the prevalence of these infections in Papua New Guinea. In 1999, serum samples were collected from 97 people in 6 villages in the remote Bensbach area of Papua New Guinea. Enzyme-linked immunosorbent assay and Western blot analyses were used to detect anti-Trichinella immunoglobulin (Ig) G and anti-cysticercus IgG in this population. The prevalence of Trichinella antibodies among inhabitants of the Bensbach area was 28.9% (28 of 97; 67.8% in men), suggesting a high consumption of poorly cooked meat. The higher prevalence of infection for Trichinella in men compared with women may be explained by the inclination of men to eat undercooked pork while hunting. All serum samples were negative for cysticercus antibodies. This is to our knowledge the first serosurvey showing anti-Trichinella antibodies in a human population living in Papua New Guinea (Australian region).

Clinical appraisal of patients and detection of serum antibodies by ELISA and CIA tests in late periods of Trichinella sp. invasion

Results of our studies using ELISA and competitive inhibition assay (CIA) tests fully confirmed the previously experienced trichinellosis and reflected persistent stimulation of antibody production due to the antigen release from Trichinella larvae, which had survived longer and undergone gradual destruction in the muscles. The studies proved that the tests complement each other, yielding concordant results in 86.7% of cases. Due to its higher specificity, the CIA test can help in interpreting pathological signs/symptoms and in evaluating humoral response activity at late and distant in time periods following the invasion.

The use of a synthetic antigen for the serological diagnosis of human trichinellosis

Hosts infected with Trichinella produce antibodies specific for an epitope common to the TSL-1 family antigens. This epitope contained uncommon terminal 3, 6-dideoxy-D-arabinohexose (so called tyvelose) residues. The disaccharide moiety was synthesized and an immunodiagnostic assay was developed, which was specific and sensitive in swine trichinellosis. We aimed to verify the specificity and sensitivity of this immunodiagnostic test in human trichinellosis. 15 sera from normal subjects, 12 from patients with other parasitic diseases and 50 from trichinellosis patients were tested. Indirect enzyme linked immunosorbent assay (ELISA) for specific IgG and an amplified ELISA for specific IgE were performed using beta-tyvelose-GalNAc-bovine serum albumin (BSA) disaccharide conjugate or T. spiralis muscle larvae excretory/secretory (E/S) products, as antigens. Neither control sera nor other parasitic infection sera resulted positive both for IgG and IgE when synthetic or E/S antigens were used. In trichinellosis patient sera, specific IgG were present in 100% of cases, irrespective of the antigen used, but whereas specific IgE were detected in 78% using E/S antigens, a 100% positivity rate was obtained, using the beta-tyvelose-BSA conjugate.

Modulation of human immune response by Echinococcus granulosus antigen B and its possible role in evading host defenses

By directly suppressing the function of certain immune cell subsets and by stimulating other cell populations related to immunopathology, parasite-derived substances play an important role in the chronic establishment of parasitic disease. Our objective was twofold: (i) to investigate further the role of Echinococcus granulosus antigen B (AgB) in the human early inflammatory response by determining its effect on polymorphonuclear cell (PMN) random migration, chemotaxis, and oxidative metabolism and (ii) to determine its action in acquired immunity by evaluating AgB and sheep hydatid fluid (SHF)-driven Th1 (gamma interferon [IFN-gamma] and interleukin 12 [IL-12]) and Th2 (IL-4 and IL-13) cytokine production by peripheral blood mononuclear cells (PBMC) from 40 patients who had cured or stable or progressive cystic echinococcosis. AgB significantly inhibited PMN recruitment but left their random migration and oxidative metabolism unchanged. Patients' PBMC stimulated with AgB produced IL-4 and IL-13 but did not produce IL-12. They also produced significantly lower IFN-gamma concentrations than did PBMC stimulated with SHF (P = 10(-5)). AgB skewed the Th1/Th2 cytokine ratios towards a preferentially immunopathology-associated Th2 polarization, predominantly in patients with progressive disease. AgB-stimulated patients' PBMC also proliferated less than SHF-stimulated PBMC (P = 9 x 10(-3)). In vitro Th2 cytokine production was reflected in vivo by elevated specific immunoglobulin E (IgE) and IgG4 antibodies binding to AgB. These findings confirm that AgB plays a role in the escape from early immunity by inhibiting PMN chemotaxis. They also add new information on the host-parasite relationship, suggesting that AgB exploits the activation of T helper cells by eliciting a nonprotective Th2 cell response.

Randomized comparison of intranasal and transdermal estradiol

OBJECTIVE

To compare the efficacy and patient acceptability of intranasal versus transdermal 17 beta-estradiol (E2) delivery systems for postmenopausal symptoms.

METHODS

Postmenopausal women were randomly assigned to intranasal 17 beta-E2, 300 microg daily (n = 176) or transdermal 17 beta-E2 (delivering 50 microg/day), two patches per week (n = 185) for 12 weeks, followed by a 4-week period with the alternate treatment. Efficacy was compared between groups using the Kupperman Index and vasomotor symptoms at week 12. Patient acceptability was compared by patient choice of administration route and by questionnaire at week 16.

RESULTS

Intranasal and transdermal therapy produced significant reductions in the Kupperman Index and in the occurrence of hot flushes and night sweats at week 12. Alleviation of climacteric symptoms was statistically equivalent in the two treatment groups (P <.001). The difference between groups in the Kupperman Index score of -0.5 +/- 0.9 (95% confidence interval -2.3, 1.3) was within the predetermined interval of equivalence. Both therapies were well tolerated with similar adverse event rates, except for moderate and severe mastalgia which was significantly less frequent with intranasal E2 (7.2%) than with the patch (15.5%, P =.02). Sixty-six percent of patients chose to continue the intranasal therapy and 34% the transdermal therapy (P <.001). Satisfaction was greater with intranasal therapy at week 16 (P <.001).

CONCLUSION

Intranasal and transdermal estrogen delivery systems had equivalent efficacy and similar safety profiles. Intranasal therapy was the patients' choice for long-term treatment.

Lymphocyte subsets in hemodialyzed HCV+ and HCV- patients

The aim of our study was to get information on the immune status of patients who undergo haemodialysis in the presence of an HCV infection. This virus infects not only hepatocytes, but also blood mononuclear cells, in particular B cells [1], but we do not know the role of this lymphocyte involvement in the maintenance and progression of hepatitis. The impairment of the cell-mediated immune response in uraemic patients is well known, for example only 50–60% of uraemic patients undergo a seroconversion after HBV vaccine, compared to 95% of the normal population. Paradoxically the immunodeficiency is concomitant with an activation of related cells which is increased rather than ameliorated by the dialysis treatment [2]. In these patients lymphocytopenia is also present with a reduction of the absolute number of T lymphocytes which remain normal in percentage. The study was performed on the following groups of subjects.

Inhibitory effects of human neutrophil functions by the 45-kD glycoprotein derived from the parasitic nematode Trichinella spiralis

AIM

We evaluated the effect of the 45-kD protein of Trichinella spiralis (gp45), purified by affinity chromatography, on random migration and chemotaxis, the oxidative metabolism of human neutrophils and on the CD11b upregulation induced by formyl-methionyl-leucyl-phenylalanine (f-MLP).

METHODS

Donor neutrophils incubated with different amounts of gp45 (0.5, 1, 1.5, 2 microg/ml) or buffer and the random migration and chemotaxis, evaluated by means of a special technique of image analysis, and the chemiluminescence response to f-MLP or phorbol myristate acetate (PMA) were analyzed. The effect on CD11b upregulation was assessed incubating cells with the protein, when activating them with f-MLP.

RESULTS

The results showed that gp45 inhibited both random and stimulated migrations, and reduced the response to f-MLP and PMA. Furthermore, gp45 significantly reduced the upregulation of the CD11b induced by f-MLP.

CONCLUSION

The results show that gp45 inhibits PMN in different functions, suggesting an anti-inflammatory action.

[Echolaparoscopy in the staging of abdominal neoplasms. Prospective study]

OBJECTIVE

To evaluate the sensitivity, specificity, positive and negative predictive value and influence on surgical strategy of laparoscopy and laparoscopic ultrasound on staging of abdominal malignancies.

MATERIAL AND METHODS

Prospective evaluation of laparoscopic ultrasound staging, according to the TNM classification, of 80 consecutive cases of abdominal malignancies in terms of sensitivity, specificity, positive and negative predictive value and influence on surgical strategy. Pathologic examination of final surgical specimens or laparoscopic biopsies was used as control.

RESULTS

Laparoscopic ultrasound evaluation was carried out successfully in 95% of cases with no mortality and morbidity. Twenty one out of 76 patients (28%) had their stage changed based on laparoscopic ultrasound findings. Unnecessary laparotomy was avoided in 11 cases (14%) due to evidence of advanced disease at laparoscopic ultrasound. For pancreatic cancer laparoscopic ultrasound was more sensitive for TNM, specificity was higher just for nodal evaluation. For liver tumor laparoscopic staging revealed more sensitive for N and M evaluation. Laparoscopic ultrasound staging had low specificity and sensitivity for T evaluation, while it was more sensitive and specific than clinical staging for nodal and distant metastasis assessment respectively for gastric and colon cancer.

CONCLUSION

Laparoscopic ultrasound staging is a safe, feasible and effective staging tool for several abdominal malignancies. The introduction of laparoscopic ultrasound probes overcomes the lack of tactile sensation proper of laparoscopy, allowing precise evaluation of both solid and deeply located abdominal structures. The use of laparoscopic ultrasound staging may help to reduce the number of unnecessary laparotomies.

Immunochemical and molecular characterization of vertebral hydatid fluid

This study describes a 42-year-old male born in Tunisia, who presented with vertebral hydatidosis which was initially misdiagnosed as Pott's disease. The correct diagnosis was finally made utilizing CT and MRI imaging and confirmation of the diagnosis was made possible by molecular and immunochemical characterization of the content of vertebral cyst fluid.

The sacrospinous vaginal vault suspension: Critical analysis of outcomes

One hundred and three women with a preoperative diagnosis of a pelvic support defect underwent right sacrospinous fixation of the vaginal apex. The procedure was performed either therapeutically (in 63 subjects with vaginal vault eversion) or prophylactically (40 patients with severe uterovaginal prolapse), and was associated with other reconstructive procedures to repair the coexisting cystocele, enterocele or rectocele. Preoperative and postoperative assessments of each vaginal site were compared and the results in the cure of stress urinary incontinence, if present, were evaluated with regard to the type of surgery performed. The overall rate of satisfactory results in the repair of the superior vaginal defect was 94%, and good anatomic results were achieved in the repair of either enterocele or rectocele. Conversely, the repair of the anterior vaginal wall was not as good as in the posterior and superior vaginal sites. Stress urinary incontinence was successfully managed in 72% of the women using different anti-incontinence procedures.

Anaphylactic response to parasite antigens: IgE and IgG1 independently induce death in Trichinella-infected mice

The response of animals infected with different Trichinella species (T. spiralis, T. britovi, T. pseudospiralis) to antigens of different Trichinella species was evaluated in outbred mice (CD1) and inbred mice (BALB/c, C3H, SJL, C57BL/6). In mice deficient for IgE or IgG1, T. spiralis only was used. In homologous conditions (i. e., same Trichinella species for antigens and infectious agent) mortality was very high (up to 100% in SJL and C57BL/6). The anaphylactic response in heterologous conditions was much lower and death was observed only in C57BL/6 and SJL mice. Experiments with deficient mice have shown that both specific IgE and IgG1 independently induce a fatal anaphylactic response.

Effects of oral and transdermal hormone replacement therapy on lipoprotein(A) and lipids: a randomized controlled trial

OBJECTIVE

Our purpose was to compare the effect of oral and transdermal hormone replacement therapy on lipoprotein(a) and other plasma lipids in healthy postmenopausal women.

DESIGN

A total of 120 postmenopausal women were enrolled in a prospective randomized controlled study, and allocated either to transdermal 17 beta-estradiol (50 micrograms/day) or to oral conjugated estrogen (0.625 mg/day). Forty-one age-matched women were used as the reference group. Plasma lipids and lipoproteins were determined every 3 months and differences were sought by statistical analysis.

RESULTS

Plasma lipoprotein(a) dropped after 3 months of treatment either with transdermal estradiol (p < 0.01) or oral estrogen (p < 0.01). Lipoprotein(a) was reduced by 12% and 22%, respectively. No further decreases were seen later on. Plasma total and low-density lipoprotein (LDL) cholesterol concentrations were decreased significantly with both treatments after 3 months of therapy. No difference was seen in the lowering effect on lipoprotein(a), LDL and total cholesterol concentrations between regimens. Plasma high-density lipoprotein (HDL) cholesterol and triglyceride concentrations increased throughout the study only in patients treated with oral estrogen.

CONCLUSIONS

These data demonstrate that hormone replacement therapy reduces the concentration of lipoprotein(a) when given both orally and transdermally. The lowering effect is achieved quickly because the maximal effect is observed after 3 months of therapy.

[Modulation of inflammatory cells in helminth infections]

In this review, different mechanisms by which helminthic parasites modulate the activities of inflammatory cells are considered. Examples are presented of parasitic products interfering with lymphocytes and their products such as antibodies, then modifying both regulation and effector response of the immune system. Furthermore, examples of interference on the complement system are illustrated. Parasites such as Ancylostoma caninum produce factors such as the neutrophil inhibitory factor (NIF) capable of inhibiting the neutrophil-endothelium adhesion, whereas Trichinella spiralis produces a glycoprotein, the 45gp, which inhibits different neutrophil functions. Parasites are also able to modulate the function of the monocytes-macrophages which in some infections play a crucial role; the modulation of NO synthesis is also relevant to the host-parasite relationship. Finally, the different anti-oxidant systems of helminthic parasites are described. The comprehension of such evasion mechanisms of the immune response is necessary to develop vaccines and new drugs, but it is also useful to clarify the contribution of parasites to immune system evolution.

Immunopathological mechanisms underlying the time-course of Trichinella spiralis cardiomyopathy in rats

The present study shows that isolated, perfused hearts from rats orally infected with Trichinella spiralis have a reduced left ventricular developed pressure (LVDP), heart rate (HR) and coronary flow (CF). This reduction is considerably enhanced by a single bolus (100 pM) of PAF (platelet activating factor, an eosinophil activator), especially at 21 days post-infection (d.p.i.), which is the time of the maximum increase in blood and tissue eosinophilia. Helminthic DNA analysis shows that, from 21 d.p.i. onwards, the morphological and functional changes in the myocardium cannot be ascribed to the parasite's presence, whereas its antigens and the attendant immunopathological reactions might have a role in the induction of myocardial damage and dysfunction. Some perivascular inflammatory cells (eosinophils and mast cells) appear to undergo degranulation. All these data suggest a complex sequence of events, from acute myocarditis (21 d.p.i.) which may lead in time (48 d.p.i. onwards) to a dilating cardiomyopathy.

Hexosaminidase in Trichinella spiralis is a single protein with alpha- and beta-subunits catalytic activities

Beta-N-acetylhexosaminidase is expressed as a single protein in Trichinella spiralis and has catalytic properties similar to the alpha- and beta-subunits of human and mouse isoenzymes A and B. It can hydrolyze the artificial substrates, 4-methylumbelliferyl-beta-D-glucosamine and 4-methylumbelliferyl-beta-D-glucosamine-6-sulphate which are respectively hydrolyzed by the beta- and alpha-subunits. The enzyme is thermostable, has a basic isoelectric point, and thus is similar to the B isoenzyme. Northern blotting experiments indicate that the enzyme is encoded by a single gene. Hexosaminidase from Trichinella spiralis shows that the substrate specificities of alpha- and beta-subunits precede the duplication of their genes.

[Trichinellosis approaching the year 2000]

Relevant information is given on the Ninth International Conference on Trichinellosis held in Mexico City from 19 to 22 August 1996. The Conference was organized in 4 Symposia and 8 Workshops. One-hundred-thirty scientific contributions (on the epidemiology, biology, systematics, immunology, biochemistry, molecular biology, pathology, legislation and control) were presented by 90 research scientists coming from 21 countries.

Lipoprotein(a) and other lipids after oophorectomy and estrogen replacement therapy

OBJECTIVE

To assess the effect of surgical menopause and subsequent estrogen replacement therapy (ERT) on lipoprotein(a) [Lp(a)] and common lipids.

METHODS

In 24 healthy premenopausal women, lipids (total cholesterol, low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, and triglycerides) and gonadotropins (FSH, LH) were measured the day before hysterectomy with bilateral oophorectomy and then after 1, 2, and 3 months. Blood was also drawn after 2, 4, 6, and 15 days to exclude the effect of surgery on Lp(a). In 19 women who volunteered for ERT, the lipid profile was assayed again after 3, 6, and 12 months of treatment.

RESULTS

Lipoprotein(a) levels rose significantly over the 3 months after surgery, from a mean +/- standard deviation (SD) 5.7 +/- 6.1 mg/dL to 10.4 +/- 9.2 mg/dL. Total cholesterol and LDL cholesterol levels increased significantly over the first 2 months; HDL cholesterol decreased significantly during the 3 months of follow-up (by 10, 17, and 20%) (P < .001). Plasma triglycerides did not change after surgery. Three months following ERT, Lp(a) and total cholesterol were significantly decreased (28 and 11%, respectively), as was LDL cholesterol (33%) after 6 months. High-density lipoprotein cholesterol increased by 24% after 6 months of treatment, and triglycerides rose significantly in the year of therapy (37%).

CONCLUSION

These findings suggest that surgical menopause induces atherogenic changes in the lipid profile in 3 months and that ERT soon reverses them.

Gonadotrophins and prolactin rise after bilateral oophorectomy for benign conditions

The aim of this study was to analyse the changes in follicle stimulating hormone (FSH), luteinizing hormone (LH) and prolactin concentrations in the 3 months following oophorectomy in pre-menopausal women operated on for benign gynaecological conditions. Included in this analysis were 21 women (mean age 47 years, range 46-52) who underwent bilateral oophorectomy plus hysterectomy for fibroids or ovarian cysts. Plasma concentrations of FSH, LH and prolactin were measured before and on days 2, 4, 6, 14 and 30 after surgery; in 10 cases measurements were made on day 60, and in five cases on day 90 after surgery. Hormone concentrations were measured in duplicate daily samples, and immunoenzymatic assay kits were used for all the immunoassays. The FSH and LH concentrations increased constantly after surgery. Mean prolactin concentrations also increased from 12.1 ng/ml before surgery to 31.5 ng/ml on day 14 after bilateral oophorectomy, but decreased thereafter to 18.2 ng/ml on day 30, 10.9 ng/ml on day 60 and 6 ng/ml on day 90. In conclusion, transient (2-3 weeks) increased prolactin concentrations are observed after surgical castration.

Inhibition of neutrophil oxidative metabolism by trichinellosis patient sera. Parasite origin or host induction?

The presence of sera factors able to inhibit both neutrophil chemotaxis and phagocytosis was observed in all patients studied at two months from infection caused by Trichinella britovi and in most of them after one year. Human neutrophils with eosinophils are able to kill T. spiralis newborn larvae in an ADCC system and their major cytotoxic mechanism is oxidative metabolism products. We evaluated the effect of trichinellosis sera on neutrophil oxidative burst to determine if neutrophils are affected by circulating factors during infection. Cells were incubated with sera from trichinellosis patients. Basal or stimulated Superoxide Anion (SA) production and chemiluminescence in response to different stimulation (PMA, f-MLP, opsonized yeasts) of neutrophils incubated with trichinellosis sera were evaluated and compared with those of cells incubated with control sera. The results show that basal SA production was inhibited by 66% of sera and stimulated by 11%. On the contrary f-MLP stimulated production was significantly increased by 22% sera, and inhibited by none. Chemiluminescence in response to f-MLP or PMA was inhibited by 46 and 80% of sera, respectively. These results show that trichinellosis sera can modulate not only SA production but also other steps of the oxidative burst, irrespective of the stimulating agent, so suggesting that different neutrophil activation pathways are affected. Increased IL-2 levels observed in most of the sera did not correlate with the inhibiting capacity of sera. The hypothesis of a parasite origin of the inhibiting factors is discussed in the light of host-parasite relationship.

Sustained prolactin release associated with precocious ovarian failure

Five women after precocious menopause and 1 patient with primary ovarian failure showed a simultaneous elevation of plasma gonadotropin and prolactin. The hypersecretion of plasma prolactin was still present 6 months after ovarian failure. After 12-18 months of observation while FSH and LH concentration remained elevated, prolactin concentrations normalized in 5 women and decreased in 1.