Streptococcus pneumoniae antibody titres in patients with primary antibody deficiency receiving intravenous immunoglobulin (IVIG) compared to subcutaneous immunoglobulin (SCIG).

Intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG) are effective in the treatment of patients with primary antibody deficiency disorders (PAD). The purpose of this study was to evaluate Streptococcus pneumoniae (Spn) antibody titres to 14 serotypes in patients receiving IVIG compared to SCIG and to correlate Spn antibody levels to clinical outcome. The doses of immunoglobulin (Ig)G/kg/month were similar in both IVIG and SCIG groups. In 11 patients treated with IVIG, Spn antibody titres were ≥ 1·3 µg/ml to 99·4 ± 2·1% of the 14 serotypes at peak IVIG but decreased to 66·9 ± 19·8% at trough IVIG. Loss of Spn titres ≥ 1·3 µg/ml was most frequent for Spn serotypes 1, 4, 9V and 23. This correlated with lower Spn antibody titres to these serotypes at peak IVIG compared to the other serotypes. In 13 patients treated with SCIG, Spn antibody titres were protective to 58·2 ± 23·3% of the serotypes 3-5 days after infusion, similar to trough IVIG. Similarly, the Spn serotypes with the least protective percentages were the same as the ones observed in trough IVIG. There were no annualized serious bacterial infections (aSBI) in either group. However, there were significantly decreased annualized other infections (aOI) in the SCIG group compared to the IVIG-treated group, 0·8 ± 0·7 versus 2·2 ± 1·2 infections/patient/year (P = 0·004). Breakthrough aOI did not correlate with protective or higher serum Spn antibody titres.

Effect of weight maintenance or gain in a 10 years period over telomere length, sirtuin 1 and 6 expression and carotid intima media thickness.

BACKGROUND: Lack of weight gain throughout adult life could mimic the beneficial effects of energy restriction in humans. The present study aimed to assess the effects of weight stability or gain, over a period of 10 years, on telomere length, sirtuin 1 and 6 expression, and carotid intima media thickness. METHODS: We studied 148 healthy adults (age range 20-59 years; 101 females) who had an objective record of their weight 10 years before. They were classified as weight losers, weight maintainers, weight gainers and extreme weight gainers. A fasting blood sample was obtained for routine laboratory and isolation of peripheral blood mononuclear cells, to extract DNA and RNA, and to measure telomere length and sirtuin 1 and 6 expression, respectively. Carotid intima media thickness was measured by ultrasound. Body composition was measured by Dual-energy X-ray absorptiometry. RESULTS: In the 10-year period, 24 participants lost weight (17 females), 65 maintained weight (41 females), 25 gained weight (15 females) and 34 were extreme weight gainers (28 females). Female weight gainers had a higher body mass index, waist circumference, total body fat and homeostatic model assessment insulin resistance. Male weight gainers had a higher hip circumference and total body fat. No differences in telomere length, sirtuin 1 expression and carotid intima media thickness were observed between weight gainers and maintainers. CONCLUSIONS: No effect of weight maintenance or gain was observed on metabolic and vascular markers of ageing.

Guidelines for the use of human immunoglobulin therapy in patients with primary immunodeficiencies in Latin America.

Antibodies are an essential component of the adaptative immune response and hold long-term memory of the immunological experiences throughout life. Antibody defects represent approximately half of the well-known primary immunodeficiencies requiring immunoglobulin replacement therapy. In this article, the authors review the current indications and therapeutic protocols in the Latin American environment. Immunoglobulin replacement therapy has been a safe procedure that induces dramatic positive changes in the clinical outcome of patients who carry antibody defects.

Biochemical characterization of acid proteases from the stomach of palometa (Pygocentrus nattereri, Kner 1858) with potential industrial application.

Pepsin is one of the major enzymes with significant importance in the food industry, biomedicines, and pharmaceutical formulations. In this work, the main objective was to biochemically characterize a pepsin-like enzymatic extract obtained from Pygocentrus nattereri, a predatory freshwater fish, focusing on their potential industrial application. The obtained extract exhibited optimal activity at 45 °C and pH 1.0-2.0. These proteases remained stable after 2 h of incubation at temperatures ranging from 0° to 45 °C and within pH range of 1.0 to 7.0. Their activity was significantly affected in presence of pepstatin A and SDS, 10 µM and 3.46 mM respectively, while EDTA and PMSF showed partial inhibitory effects. Divalent cations (Ca2+ and Mg2+) did not inhibit the proteolytic activity of the extract; in fact, it improved at a 5 mM CaCl2 concentration. As the NaCl concentration increased, the enzyme activity decreased. However, after desalination, 90 % of the activity was recovered within the tested exposure time. Besides, this extract demonstrated exceptional versatility across diverse industrial applications, including collagen extraction augmentation, IgG hydrolysis facilitation, and silver and polyester recovery from X-ray films. Our results suggest that the obtained enzymatic extract has a wide range of potential applications.

Advancing the management of primary immunodeficiency diseases in Latin America: Latin American Society for Immunodeficiencies (LASID) Initiatives.

Primary immunodeficiency diseases (PIDD) are associated with significant morbidity and mortality and result in a significant public health burden. This is in part due to the lack of appropriate diagnosis and treatment of these patients. It is critical that governments become aware of this problem and provide necessary resources to reduce this impact on health care systems. Leading physicians in their respective countries must be supported by their own governments in order to implement tools and provide education and thus improve the diagnosis and treatment of PIDD. The Latin American Society of Primary Immunodeficiencies (LASID) has initiated a large number of activities aimed at achieving these goals, including the establishment of a PIDD registry, development of educational programmes and guidelines, and the introduction of a PIDD fellowship programme. These initiatives are positively impacting the identification and appropriate treatment of patients with PIDD in Latin America. Nevertheless, much remains to be done to ensure that every person with PIDD receives proper therapy.

Primary immunodeficiency diseases in Latin America: proceedings of the Second Latin American Society for Immunodeficiencies (LASID) Advisory Board.

Early diagnosis and appropriate therapy are essential for the best prognosis and quality of life in patients with primary immunodeficiency diseases (PIDDs). Experts from several Latin American countries have been meeting on a regular basis as part of an ongoing effort to improve the diagnosis and treatment of PIDD in this region. Three programmes are in development that will expand education and training and improve access to testing facilities throughout Latin America. These programmes are: an educational outreach programme (The L-Project); an immunology fellowship programme; and the establishment of a laboratory network to expand access to testing facilities. This report provides the status of these programmes based on the most recent discussions and describes the next steps toward full implementation of these programmes.

Critical issues and needs in management of primary immunodeficiency diseases in Latin America.

Experts from six Latin American countries met to discuss critical issues and needs in the diagnosis and management of primary immunodeficiency diseases (PIDD). The diagnosis of PIDD is generally made following referral to an immunology centre located in a major city, but many paediatricians and general practitioners are not sufficiently trained to suspect PIDD in the first place. Access to laboratory testing is generally limited, and only some screening tests are typically covered by government health programmes. Specialised diagnostic tests are generally not reimbursed. Access to treatment varies by country reflecting differences in healthcare systems and reimbursement policies. An online PIDD Registry Programme for Latin America has been available since 2009, which will provide information about PIDD epidemiology in the region. Additional collaboration across countries appears feasible in at least two areas: a laboratory network to facilitate the diagnosis of PIDD, and educational programmes to improve PIDD awareness. In total, these collaborations should make it possible to advance the diagnosis and management of PIDD in Latin America.

Systemic alterations induced by a Bothrops alternatus hemorrhagic metalloproteinase (baltergin) in mice.

Systemic alterations induced by a Bothrops alternatus hemorrhagin, named baltergin, a 55kDa fibrinogenolytic metalloproteinase isolated from venom of north-eastern Argentina specimens, were studied in mice. It caused macroscopic hemorrhagic spots in lungs which was injected intravenously with a minimum pulmonary hemorrhagic dose of 10microg. Histological observations of lungs showed mainly hemorrhagic areas, evidenced by the presence of erythrocytes in the alveolar spaces, congestion and increase of thickness of alveolar septum due to polymorphonuclear infiltrate and mononuclear cells. Neither macroscopic hemorrhage in other organs nor histological alterations in heart and cerebrum/cerebellum were observed at doses assayed. However, kidney and liver were mildly affected. Kidney examination revealed congestion, subcapsular hemorrhage with local capsule detachment, inflammatory infiltrate and degeneration of tubular cells. Congestion of blood vessels and hydropic degeneration of hepatocytes were observed in liver. Besides, baltergin was able to further hydrolyze type IV collagen. Although the enzyme showed to be less lethal than whole venom, it induced severe pulmonary bleeding and affected kinder and liver in minor grade. In conclusion, baltergin is able to alter the integrity of capillary vessels and simultaneously, to interfere on the hemostatic system. Thus, this metalloproteinase contribute markedly to systemic alterations characteristic of B. alternatus envenomations.

Purification and characterization of patagonfibrase, a metalloproteinase showing alpha-fibrinogenolytic and hemorrhagic activities, from Philodryas patagoniensis snake venom.

Venoms of Colubridae snakes are a rich source of novel compounds, which may have applications in medicine and biochemistry. In the present study, we describe the purification and characterization of a metalloproteinase (patagonfibrase), the first protein to be isolated from Philodryas patagoniensis (Colubridae) snake venom. Patagonfibrase is a single-chain protein, showing a molecular mass of 53,224 Da and an acidic isoelectric point (5.8). It hydrolyzed selectively the Aalpha-chain of fibrinogen and when incubated with fibrinogen or plasma, the thrombin clotting time was prolonged. Prominent hemorrhage developed in mouse skin after intradermal injection of patagonfibrase. When administered into mouse gastrocnemius muscle, it induced local hemorrhage and necrosis, and systemic bleeding in lungs. Patagonfibrase showed proteolytic activity toward azocasein, which was enhanced by Ca(2+) and inhibited by Zn(2+), cysteine, dithiothreitol and Na(2)EDTA. Patagonfibrase impaired platelet aggregation induced by collagen and ADP. Thus, patagonfibrase may play a key role in the pathogenesis of disturbances that occur in P. patagoniensis envenomation, and may be used as a biological tool to explore many facets of hemostasis.

Antibody response to pneumococcal capsular polysaccharide vaccine in Down syndrome patients.

The majority of children with Down syndrome (DS) tend to have frequent bacterial infections including recurrent respiratory infections. Our objective was to evaluate the production of antibodies to pneumococcal polysaccharide antigens after active immunization in DS subjects. IgG antibodies to pneumococcal serotypes (1, 3, 6B, 9V, and 14) were measured before and 6 weeks after immunization with a 23-valent pneumococcal vaccine (Pneumo23, Pasteur-Merrieux) in 6- to 13-year-old DS children (N = 17) and in aged-matched normal controls (N = 30). An adequate response was defined as a 4-fold increase over baseline or a post-immunization level of specific pneumococcal serotype antibody > or = 1.3 microg/mL. After immunization, all DS children had an increase in post-immunization levels against all serotypes analyzed. A 4-fold or more increase was observed in all DS children concerning serotypes 1 and 14, in 90% of subjects for serotypes 3 and 9V, and in 65% for serotype 6B. Regarding this increase, 8 of the 17 DS children had an adequate response to all serotypes analyzed, 8/17 patients to 4 serotypes and 1/17 to 3 serotypes. However, when we compared post-immunization levels between DS children and controls, we observed lower levels in the former group (P < 0.05) for all serotypes except serotype 3. We conclude that pneumococcal polysaccharide immunization could be beneficial for these DS children.

Premature loss of muscle mass and function in type 2 diabetes.

INTRODUCTION: Muscle mass and function are among the most relevant factors that contribute to an optimal quality of life, and are strong predictors of mortality in the elderly. Loss of lean tissues and deterioration of muscle function have been described as one of the many complications of type 2 diabetes mellitus (DM2), but most studies do not isolate age as an intervening factor. AIM: To study whether adult DM2 patients up to 60years of age have decreased muscle mass and function compared with healthy non-diabetic (ND) subjects of similar age. METHODOLOGY: Appendicular fat-free mass (ApFFM) by dual X-ray absorptiometry (DEXA), handgrip strength (HS), quadriceps strength (QS), 12 min walking capacity (12MW) and the Timed Up and Go test (TUG) were measured in 100 DM2 patients and 39 ND controls. Muscle quality, or the ratio between lean mass and muscle strength of upper and lower limbs, and the functional limitations associated with pain and stiffness assessed according to the Western Ontario and McMaster Universities Arthrosis Index (WOMAC) were also recorded. Specific tests were performed to rule out microvascular diabetic complications (retinal and peripheral nerves), metabolic control, kidney function and vitamin D status and examine their association with ApFFM and function. RESULTS: ApFFM was significantly higher among DM2 female patients and lower among diabetic men. However opposite results were obtained when individual values were corrected for body mass index (BMI), specifically among women, who were more likely to be obese. As for muscle strength and global functionality tests, significantly better performances in TUG, 12MW, QS and HS were observed among ND subjects of both sexes. These differences prevailed even after excluding diabetic patients with microvascular complications as well as those with more than 10years of diabetes. Muscle quality was also significantly better among ND women. Higher scores of pain and stiffness in the WOMAC scale correlated with 12MW and TUG in both groups but did not correlate with ApFFM. CONCLUSIONS: We found a clear deterioration of lean mass and muscle functions among adult DM2 patients of up to 60years old, independent of length of disease, metabolic control, vitamin D status and presence of microvascular complications and pain.

Duvernoy's gland secretion of Philodryas patagoniensis from the northeast of Argentina: its effects on blood coagulation.

Duvernoy's gland secretion of Philodryas patagoniensis exhibits high hemorrhagic activity, containing enzymes that are able to degrade the vascular wall. In this work we aim to determine if the secretion can also affect the hemostatic system by causing changes in blood coagulation. Procoagulant and coagulant activities were evaluated on plasma and fibrinogen, respectively. The delay in the thrombin clotting time of fibrinogen previously incubated with the secretion was also determined. Specific hydrolysis of fibrinogen and fibrin incubated with the secretion at different time intervals was shown by electrophoresis on polyacrylamide gel. To determine the structural characteristics of the enzymes degrading fibrinogen and fibrin, secretion were incubated in the presence of 45 mM Na(2)EDTA, 40 mM Benzamidine, and/or 2 mM PMSF before the incubation with fibrinogen or fibrin, respectively. The effect in vivo was investigated in adult male rats injected with different dose of secretion, aliquots of blood were withdrawn at different time intervals, and the fibrinogen concentration was determined. Duvernoy's gland secretion of P. patagoniensis did not clot plasma or fibrinogen. It exhibited a potent fibrinogenolytic activity degrading the Aalpha-chain faster than the Bbeta-chain, whereas gamma-chain was resistant. This latter corresponded with a strong delay in the thrombin clotting time of fibrinogen (4 mg/ml) pre-incubated with the secretion, being 9.53 microg the amount of protein from Duvernoy's gland secretion that increased the thrombin clotting time from 20 to 60 s. In vivo, the loss of rat plasma fibrinogen was proportional to the amount of secretion injected. The secretion also hydrolyzed fibrin degrading the alpha-monomer. Inhibition studies with Na(2)EDTA, Benzamidine, and/or PMSF showed that metalloproteinases and serinoproteinases are the main enzymes responsible for the hydrolyzing activity on fibrinogen and fibrin. All these results demonstrate that Duvernoy's gland secretion of P. patagoniensis possesses enzymes able to hydrolyze plasma components playing a relevant role in the blood coagulation. These hydrolyzing activities and those acting on the wall of blood vessels let the secretion exhibit a high hemorrhagic activity, which may result in permanent sequelae or even cause the death of the victims bitten by this colubrid snake.

Proteolytic, edematogenic and myotoxic activities of a hemorrhagic metalloproteinase isolated from Bothrops alternatus venom.

A hemorrhagic metalloproteinase has been isolated from Bothrops alternatus venom from specimens that inhabit the north-east region of Argentina. The present study aimed at evaluating the proteolytic, hemorrhagic, edematogenic and myotoxic activities of the purified metalloproteinase, in order to consider its participation on the phatophysiology of the intoxication by Bothrops alternatus venom. The hemorrhagic metalloproteinase was isolated by a combination of DEAE-Cellulose chromatography and gel filtration on Sephadex G-75. The enzyme showed a molecular mass around 55k Da, it exhibited a hemorrhagic activity with a minimal hemorrhagic dose of 1.9 microg, almost two fold minor than the whole venom (3.6 microg). The enzyme showed a weak proteolytic activity on casein (18.72 U/mg enzyme), similar to the one exhibited by the whole venom (20 U/mg venom). Besides, the ability to degrade casein could be detected by SDS-PAGE; beta-casein was the fraction that showed the higher degradation, followed by alphas(1)-casein and kappa-casein degradation. The hemorrhagic metalloproteinase rapidly hydrolysed the A alpha-chain of fibrinogen, followed by B beta-chain degradation and leaving the gamma-chain unaffected. Proteolytic activities were inhibited by EDTA whereas they were not inhibited by benzamidine and PMSF. The metalloproteinase showed several polypeptides chains after autocatalytic processing, including a chain of 28k Da, it could be the processed disintegrin-like and cysteine-rich domains. The isolated enzyme exhibited myotoxic activity with high CK levels at 6h, due to local ischemia resulting of its hemorrhagic activity, and a significant edema-inducing effect (MED=1.3 microg), corroborated both results by the histological observations of samples of gastrocnemius muscle. These findings showed that this hemorrhagic metalloproteinase, possesses high edematogenic and myotoxic activities and, in despite of exhibiting a weak proteolytic activity, it is able to degrade fibrinogen. So, this enzyme would contribute markedly to the phatophysiology of the bothropic envenomation.

Skeletal muscle ceramide species in men with abdominal obesity.

BACKGROUND: Obesity is a risk factor for diabetes and its consequences, including accelerated ageing and mortality. The underlying factor could be accumulation of certain lipid moieties, such as ceramides (CER) and diacylgycerol (DAG) within muscle tissue, which are known to promote insulin resistance (IR), induce inflammation and oxidative injury, ultimately altering muscle function. AIM: First, to study the relationship between body composition and age (independent variables) with skeletal muscle accumulation of lipid species, oxidative injury and strength. Second, to analyze the relationship between muscle tissue metabolites and insulin resistance, inflammation and lymphocyte telomere length, the latter as an indicator of ageing. METHODOLOGY: The sample included 56 healthy sedentary males, scheduled for inguinal hernia surgery, aged 27 to 80 y. Each individual was subject to anthropometric measurements, body composition assessment through radiologic densitometry (DEXA), measurement of handgrip and quadriceps strength, serum biochemical parameters (lipoproteins, creatinine, high sensitivity C reactive protein [hsCRP], fasting and post glucose insulin and glucose concentrations for calculation of IR through the Matsuda and HOMA-IR indexes), and extraction of peripheral leukocytes for measurement of telomere length. During the surgical procedure, a sample of muscle tissue was obtained (anterior abdominal oblique) in order to measure CER and DAG (and sub species according to chain length and saturation) by mass spectrometry, 4 hydroxy-2-nonenal adducts (4-HNE) using electron microscopy immunohistochemistry, and carboxymethyl-lisine (CML) by immunohistochemistry, the latter as indicators of oxidative stress (OS). RESULTS: Body mass index (BMI) of twenty six individuals was > 25 k/m2, while BMI of 7 was > 30 k/m2. Overweight/obese individuals, did not exhibit differences in skeletal muscle lipid metabolites, however total CER and specific long chain CER sub-species (20 and 22 carbon) increased significantly among individuals with a central fat distribution (n = 14) as well as in glucose intolerant subjects (n =23). A negative association was found between mononuclear leukocyte telomere length and 20 and 22 carbon CER (rho = - 0.4 and -0.5 0 p < 0.05). Muscle strength was not associated with any of the measured muscle metabolites or markers of OS. A multiple regression analysis accepted central abdominal fat and telomere length as significant predictors of CER (R2 = 0.28). CONCLUSIONS: An association was found between accumulation of specific ceramide species in muscle tissue and abdominal obesity, glucose intolerance and shortening of leukocyte telomeres, although not with muscle oxidative injury or dysfunction.

Peripheral blood mononuclear cell sonicates as an alternative to irradiated allogeneic cells to stimulate a mixed lymphocyte reaction and to enumerate CD69+ alloreactive T cells.

An alloreactive reaction similar to that occurring during GvHD can be generated in a mixed lymphocyte culture. The presence of both stimulator and responder cells in these cultures makes the identification and enumeration of alloreactive cells difficult and unreliable. We describe the use of PBMC sonicates as an alternative to the standard MLC method to stimulate an allogeneic reaction. Using combinations of autologous or allogeneic PBMC sonicates, we showed that the lymphocyte proliferative response to cell sonicates was comparable to the response using irradiated cells. The proliferative response was concentration dependent and reached maximum levels at day 6. Both irradiated cells and PBMC sonicates induced significantly lower responses when the stimulating cells were partially HLA-DR matched rather than completely mismatched. Alloreactive T cells stimulated with sonicates were enumerated by the flow cytometric detection of CD69 or CD25. In HLA-mismatched cultures, approximately 7% of CD3+ T cells were CD69+ or CD25+, suggesting alloreactivity. Although there was a significant correlation between the expression of these activation markers and lymphocyte proliferative responses, significant individual variations in the results of these two assays were observed. The results in this study demonstrate the potential of using PBMC sonicates instead of irradiated lymphocytes for the study and identification of alloreactive cells at the cellular and molecular level.

Quantitation of soluble HLA class I heterodimers and beta 2-microglobulin in patients with active pulmonary tuberculosis.

Beta 2m serum levels have been shown to be increased in patients with tuberculosis and HIV infection. We determined the stability of beta 2m and of sHLA-I dimers in serum, and then determined the levels of both molecules in 60 non-HIV-infected patients with active pulmonary tuberculosis and in 55 adult controls. The levels of sHLA-I in samples kept at room temperature declined by 8% at 30 minutes, 16% at 60 minutes, and 36% at 120 minutes. Beta 2m levels remained stable at all times tested. Mean sHLA-I levels were 0.99 +/- 0.16 micrograms/ml in controls and 1.34 +/- 0.11 micrograms/ml in patients with tuberculosis (P < 0.0001). Beta 2m levels were 1.23 +/- 0.26 micrograms/ml in controls and 2.26 +/- 0.64 micrograms/ml in patients with tuberculosis (P < 0.0001). All patients with tuberculosis had elevation of sHLA-I and/or beta 2m above 1 standard deviation of normal values. However, there was no correlation between sHLA-I and beta 2m levels in individual samples. Evaluation of sHLA-I holds the promise of further understanding of the biology and genetic regulation of the immune response to mycobacterial infection.

Response to a heptavalent conjugate Streptococcus pneumoniae vaccine in children with recurrent infections who are unresponsive to the polysaccharide vaccine.

OBJECTIVE: To determine whether children with recurrent respiratory infections who failed to respond to the conventional polysaccharide vaccine would respond to a pneumococcal conjugate vaccine. METHODS: Children referred to our clinic for recurrent respiratory infections who had no known primary or secondary immunodeficiencies were immunized with a 23-valent pneumococcal polysaccharide vaccine. IgG antibodies to pneumococcal serotypes 1, 3, 4, 6B, 9V, 14, 18C, 19F and 23F were determined by enzyme-linked immunosorbent assay before and 4 to 6 weeks after immunization. An adequate IgG antibody response to an individual serotype was arbitrarily defined as a postimmunization antibody titer > or =1.3 microg/ml or at least 4 times the preimmunization value. Immunization with an experimental CRM197-heptavalent pneumococcal conjugate vaccine was offered to patients without an adequate response to 4 or more vaccine serotypes (nonresponders). Post-conjugate immunization antibody concentrations were measured 4 to 6 weeks later. RESULTS: In nonresponder patients (n = 17) geometric mean post-conjugate immunization (C) serum antibody concentrations (microg/ml) compared with post-polysaccharide (PS) concentrations were: (serotype, C vs. PS) 4, 1.11 vs. 0.30 (P = 0.000227); 6B, 0.46 vs. 0.20 (P = 0.017267); 9V, 0.82 vs. 0.29 (P = 0.002163); 14, 1.88 vs. 0.27 (P = 0.000615); 18C, 0.98 vs. 0.32 (P = 0.021962); 19F, 1.24 vs. 0.34 (P = 0.002844); and 23F, 0.87 vs. 0.16 (P = 0.000194). In responder patients (n = 67), after 1 dose of the polysaccharide vaccine, geometric mean antibody concentrations were: 4, 1.05; 6B, 0.96; 9V, 1.55; 14, 1.65; 18C, 1.62; 19F, 1.30; and 23F, 1.02. CONCLUSIONS: Our results show that a pneumococcal conjugate vaccine is capable of inducing an IgG response in patients with recurrent infections who had failed to mount an adequate response to the polysaccharide vaccine. Conjugate vaccines may be of value in the management of children with recurrent pneumococcal respiratory infections.

Mansonella ozzardi in Haiti. IV. Evaluation of antibody reactivity to heterologous antigens.

Sera from individuals in an area of Haiti endemic for Mansonella ozzardi were analyzed for reactivity to antigens of Brugia pahangi, Dirofilaria immitis, Mansonella llewellyni or Ascaris lumbricoides using either an enzyme-linked immunosorbent assay or an indirect immunofluorescent antibody test. IgM and IgG reactivity to all antigens was observed with sera from both microfilaremic and amicrofilaremic individuals when compared to reactivity of sera from individuals from nonendemic areas. Antibody reactivity to B. pahangi was greater than that to other antigens. IgG reactivity of sera from endemic patients to filarial antigens was consistently greater than that of IgM. Antibody reactivity was not correlated with age or microfilarial density.

Bancroftian filariasis in Haiti: preliminary characterization of the immunological responsiveness of microfilaremic individuals.

Patent infections with the lymphatic filariae, Wuchereria bancrofti and Brugia malayi, are associated with suppressed in vitro cellular responsiveness to filarial antigens. In studies of bancroftian filariasis in Haiti, a significant number of microfilaremic individuals can be characterized as "responders" to filarial antigens. Cells from 37/74 untreated microfilaremic subjects responded to B. pahangi antigen (stimulation ratio greater than 2) as detected by in vitro blastogenesis. A comparison of responders to nonresponders revealed a significant difference in mean B. pahangi reactivity (15,822 vs. 4,538 cpm, P less than 0.001), but no significant differences with respect to age, microfilaremia, PPD or PHA reactivity, or B. pahangi-specific antibody levels. Subtle differences may exist between these groups with respect to recognition of specific antigens on Western blots.

Effect of human newborn BCG immunization on monocyte viability and function at 3 months of age.

SETTING: Immune response induced by BCG vaccination seems to reflect the development of T-cell immunity and monocyte activation. Participants were recruited from a large prospective study in infants from a suburb in Santiago, Chile. OBJECTIVE: To determine whether newborn BCG immunization changes the innate ability of cultured monocyte-macrophages to ingest and kill virulent mycobacteria in the absence of lymphocytes. DESIGN: The study population consisted of 15 three-month-old, tuberculin-positive infants immunized with BCG (Japanese) at birth, 13 randomly-selected, age-matched tuberculin-nonreactive infants in whom BCG immunization was postponed until one year of age, and five BCG-immunized, tuberculin-reactive adults. Adherent cells were cultured for 48 h. Monocyte-macrophage viability and number and viability of intracellular Mycobacterium tuberculosis bacilli were assessed after an additional 2 h and 4 and 7 days of incubation. RESULTS: There was no difference in the mean number of adherent cells present after 48 h among the three study groups. Adherent cells from BCG-immunized infants and adults had a significantly higher viability after 7 days in culture than adherent cells from non-immunized infants. The percentage of cells ingesting M. tuberculosis and the number of bacilli per cell after 2 h and 4 days was significantly higher in immunized infants and adults than in non-immunized infants. However, there was no evidence for increased killing of mycobacteria by cells from immunized infants and adults. CONCLUSION: These results suggest that BCG vaccination increases monocyte viability and the uptake of M. tuberculosis without enhancing the ability to kill ingested M. tuberculosis in the absence of lymphocytes.