Whole Blood Cultures Research Articles

Cellular Immune Responses to Recombinant Antigens in Pregnant Women Chronically Infected with Toxoplasma gondii

The parasite Toxoplasma gondii can infect most mammals and birds, sometimes causing severe pathology. Primary infection during pregnancy can result in abortion or fetal defects. Host immunity, particularly cellular immunity towards antigenic peptides, can control infection, but an efficient vaccine is not yet available. We have evaluated T-cell responses to a crude soluble toxoplasma antigen (ST-Ag) and to five recombinant peptide antigens of cells in whole-blood cultures from 22 pregnant women with preexisting infections and from 7 pregnant negative controls. Cells from all infected patients but from none of the controls responded specifically to ST-Ag by expressing surface CD25 on culture. Responses to the recombinant antigens showed considerable variation between individuals. rGRA1 elicited a response in 16 of the 22 samples (73%), rSAG1 in 13, rGRA7 in 9, rGRA6-CT in 4, and rGRA6-NT in only 1. Most responding cells were CD4(+). Cells from infected subjects cultured with ST-Ag all released high levels of gamma interferon (IFN-gamma) into the culture supernatant (4,343 +/- 2,536 pg/ml). Cells from 12 patients released IFN-gamma after culture with rGRA1 (130 +/- 98 pg/ml), those from 10 patients released it after culture with rSAG1 (183 +/- 128 pg/ml), and those from 4 patients released it after culture with rGRA7 (324 +/- 374 pg/ml). Intensity of IFN-gamma production in response to the latter two recombinant antigens correlated with responses to ST-Ag (r = 0.61 and 0.53, respectively; P < 0.01). Interleukin-4 was always absent from supernatants of cells stimulated with toxoplasma antigens. The heterogeneity of human responses to individual recombinant toxoplasma antigens should be considered in the design of potential vaccines.

Influence of GSTM1 and GSTT1 genotypes on sister chromatid exchange induction by styrene in cultured human lymphocytes.

Glutathione S-transferases M1 (GSTM1) and T1 (GSTT1) are polymorphically expressed in humans; about 47% and 13% of Finns lack the GSTM1 and GSTT1 activity due to homozygous deletion of the respective genes (null genotypes). We previously observed that GSTT1 null genotype was associated with increased induction of sister chromatid exchanges (SCEs) by a metabolite of styrene, styrene-7,8-oxide, in human lymphocyte cultures, while GSTM1 genotype had no effect. In the present study, we examined the potential effect of these genotypes on SCE induction by the parent compound styrene. Seventy-two hour whole-blood lymphocyte cultures from 24 healthy human donors, representing all different combinations of these genotypes, were examined. In agreement with our earlier findings, styrene was an efficient inducer of SCEs in cultures of all donors. In two separate experiments, the mean number of SCEs/cell induced by 1.5 mM styrene was 1.55 times (P = 0.011) or 1.34 times (P = 0.015) higher in subjects lacking both GSTM1 and GSTT1 than in subjects having both genes. Donors null for only one of the genes showed intermediate SCE induction by styrene. At 0.5 mM styrene, no clear differences in SCE rates among the genotypes were seen. Our results suggest that the concurrent lack of the GSTM1 and GSTT1 genes increases the genotoxic effects of styrene in human cells. The discrepant findings obtained for the importance of GSTM1 genotype in modulating the genotoxic effects induced by styrene-7,8-oxide and styrene may reflect a difference between a direct treatment with styrene-7,8-oxide and its formation from styrene in the cells. Although glutathione conjugation is a minor route in styrene detoxification in human liver in vivo, individual sensitivity associated with GSTM1 and GSTT1 null genotypes may be important locally in blood circulation and in blood-forming organs.

Influence of Specimen Age and Use of Different Negative Controls in Determination of Intracytoplasmic Levels of Cytokines after Whole-Blood Culture Assay

Influence of Specimen Age and Use of Different Negative Controls in Determination of Intracytoplasmic Levels of Cytokines after Whole-Blood Culture Assay

Chromosomal response of human lymphocytes to streptozotocin

The induction of chromosomal aberrations (CAs) and sister-chromatid exchanges (SCEs) by the methylating agent streptozotocin (STZ) and the effect of this compound on mitotic index (MI) and cell cycle progression in human lymphocytes were investigated. Unstimulated (G 0) or cycling lymphocytes derived from whole blood or purified lymphocyte cultures were pulse-treated with increasing doses of STZ for 0.5–24 h. Induction of CAs by STZ was only observed in cycling lymphocytes derived from whole blood cultures (WBC) ( P<0.05). On the contrary, STZ produced a significant and dose–response increase in the yield of SCEs in unstimulated as well as cycling lymphocytes ( P<0.05). In addition, STZ induced a dose-dependent decrease in the MI but had a slight effect on cell cycle progression. These results suggest that SCEs are the most sensitive endpoint for evaluating the chromosomal effects of STZ on these cells.

The role of endogenous interleukin (IL)-18, IL-12, IL-1beta, and tumor necrosis factor-alpha in the production of interferon-gamma induced by Candida albicans in human whole-blood cultures.

Despite the importance of interferon (IFN)-gamma, tumor necrosis factor (TNF), and interleukin (IL)-18 for host defense against candidiasis, the pathways leading to their stimulation by Candida albicans are unclear. In a whole-blood model, IL-18 neutralization by IL-18 binding protein decreased C. albicans-induced IFN-gamma synthesis by 72%. Similarly, neutralization of IL-12 or IL-1beta by either neutralizing antibodies or IL-1 receptor antagonist also reduced (by 65%) IFN-gamma production. Neutralization of TNF by TNF binding proteins resulted in only a 36% reduction of IFN-gamma synthesis. In contrast, production of TNF and IL-8 was largely unaffected by these cytokine inhibitors. Thus, C. albicans stimulates IFN-gamma production in an IL-18-, IL-12-, and IL-1beta-dependent manner, whereas production of TNF and IL-8 is independent of these cytokines. Blocking the biologic activities of IL-18, IL-12, and IL-1beta in patients (e.g., for treatment of autoimmune diseases) may result in increased susceptibility to C. albicans infection.

Influence of Specimen Age and Use of Different Negative Controls in Determination of Intracytoplasmic Levels of Cytokines after Whole-Blood Culture Assay

Intracytoplasmic detection of cytokines by flow cytometry has become a powerful tool in the characterization of cytokine-producing cells. However, it is not known to what extent specimen age and the use of various negative controls may influence the amount of cytokine-positive cells. We therefore compared different times of storage and the use of several negative controls in the determination of intracytoplasmic levels of cytokines. There was a substantial decline of interleukin-2- and gamma interferon-positive lymphocytes after 20 h and especially after 48 h of storage. The precision of intracytoplasmic interleukin-6 determination decreases after long-term storage compared to 2 h of storage, whereas the amount of interleukin-8-positive monocytes remained rather stable. Therefore, we recommend performing the analysis as fast as possible after the blood sample is drawn. Under consideration of isotype-matched antibodies and nonstimulated cells as negative controls instead of the purified antibody-blocking control, strikingly higher amounts of interleukin-2-, gamma interferon, interleukin-6-, and interleukin-8-positive cells were found. For a meaningful interpretation of data these differences have to be kept in mind. Further studies should evaluate the exact specificity of these controls.

Effect of different adjuvants on the immune responses of cattle vaccinated with Mycobacterium tuberculosis culture filtrate proteins

The development of improved vaccines for bovine tuberculosis is urgently required as a cost effective solution for control and eventual eradication of tuberculosis in domestic animals. Studies in small animal models of tuberculosis have shown that vaccination with culture filtrate proteins (CFP), prepared from Mycobacterium tuberculosis or M. bovis, can induce cellular immune responses and confer a level of protection against aerogenic challenge with virulent mycobacteria. As a first step in the development of a mycobacterial CFP vaccine for protection of cattle against bovine tuberculosis, the immune responses of cattle vaccinated with short-term culture filtrate proteins (ST-CFP) from M. tuberculosis and formulated with different adjuvants were compared with those vaccinated with bacille Calmette–Guerin (BCG). The adjuvants included dimethyldioctyldecyl ammonium bromide (DDA), diethylaminoethyl (DEAE)-dextran, and ST-CFP adsorbed onto polystyrene beads. Vaccination with ST-CFP/DEAE-dextran induced high levels of interleukin-2 (IL-2) but low levels of interferon-γ (IFN-γ) from whole-blood cultures stimulated with M. tuberculosis ST-CFP in comparison with the strong IFN-γ and IL-2 responses induced after vaccination with BCG. ST-CFP/DEAE-dextran also induced a strong antigen-specific immunoglobulin antibody response with both immunoglobulin G1 (IgG1) and IgG2 isotypes. Vaccination with ST-CFP/beads induced a weak IgG1-biased antibody response but no IFN-γ or IL-2 response. DDA did not induce significant immune responses in animals vaccinated with ST-CFP. In comparison to the moderate delayed-type hypersensitivity (DTH) responses induced by vaccination with subcutaneous BCG, none of the ST-CFP vaccines induced a significant DTH response to either M. tuberculosis ST-CFP or bovine purified protein derivative (PPD). While the ST-CFP vaccines used in this study have not induced strong antigen-specific cellular immune responses in cattle comparable to those induced by BCG, they are immunogenic in cattle and it may be possible to overcome this problem by using adjuvants that more effectively promote IFN-γ responses in this species.

Mechanical ventilation alters the immune response in children without lung pathology.

. Objective: This study was undertaken to examine the hypothesis that mechanical ventilation in association with anesthesia would alter the cytokine profile in infants without preexisting lung pathology. Design and setting: Prospective observational study in pediatric intensive care unit in a university hospital. Patients: Twelve infants who were subjected to an uncomplicated diagnostic cardiac catheterization procedure were studied. All subjects were ventilated with a volume control mode, 0.3 FIO2, 4 cmH2O PEEP, and 10 ml/kg tidal volume. Volatile (servoflurane) anesthetics were given. Measurements and results: Tracheal aspirates and blood samples were obtained before and after 2 h of mechanical ventilation. In tracheal aspirates and in supernatants of stimulated whole-blood cultures cytokine concentrations were measured. In the tracheal aspirates the immune balance was characterized by a proinflammatory response pattern, with a significant increase in TNF-α and IL-6 concentrations; concentrations of anti-inflammatory mediators remained very low. The functional capacity of peripheral blood leukocytes to produce INF-γ, TNF-α, and IL-6 in vitro was significantly decreased. This was accompanied by a significant decrease in the killing activity of natural killer cells. Conclusions: Two hours of servoflurane and mechanical ventilation using a tidal volume of 10 ml/kg is associated with remarkable changes in the immune response in infants without preexisting lung pathology undergoing cardiac catheterization. In the lungs the immune balance favors a proinflammatory response pattern without detectable concentrations of anti-inflammatory mediators. The Th1 immune response by peripheral blood leukocytes was decreased. The observed change in Th1/Th2 balance in favor of Th2 cytokine activity may be a systemic adaptation to the proinflammatory milieu in the lung.

Increased IL-10 production by stimulated whole blood cultures in primary IgA nephropathy.

Most patients with primary IgA nephropathy (IgAN) have a significantly higher memory repertoire of IgA1-producing B lymphocytes in their bone marrow together with high plasma levels of IgA1. The connection between the mucosal immune system and the bone marrow compartment is probably based on traffic of either antigen-presenting cells (APC) or antigen-specific lymphocytes. Cytokines play an important role in the proliferation and differentiation of lymphoid cells. In order to mimic the in vivo situation as much as possible, we assessed cytokine production profiles ex vivo in 23 IgAN patients and matched controls, using lipopolysaccharide (LPS)- or phytohaemagglutinin (PHA)-stimulated whole blood (WB) cultures. Interferon-gamma (IFN-gamma), IL-2, IL-6, IL-10 and tumour necrosis factor-alpha (TNF-alpha) production in culture supernatants were determined by cytokine-specific ELISAs. Compared with controls, PHA-stimulated cultures resulted in significantly higher IL-10 (P<0.001), IL-2 (P<0.005) and IFN-gamma (P<0.001) levels in IgAN patients, but no significant differences in TNF-alpha or IL-6 levels were found. In LPS-stimulated cultures, the only significant difference (P<0.001) between the two groups was the increased IL-10 production in IgAN patients. The enhanced cytokine production in stimulated WB cultures suggests altered monocyte-related T cell responses in patients with IgAN. Increased IL-10 production may eventually result in an increased number of IgA-producing B lymphocytes in the bone marrow. In addition, high levels of endogenous IL-10 may down-regulate the effector functions of monocytes, or possibly APC in general, and consequently the IgA response at the mucosal level.

DIFFERENTIAL RATES OF CYTOKINE PRODUCTION AND APOPTOSIS IN VENIPUNCTURE AND FINGER-STAB DERIVED BLOOD CULTURES

The collection of finger-stab (FS) blood is a convenient and non-invasive method of rapidly acquiring human blood and is becoming increasingly popular for use in human biomonitoring studies. This study compared whole blood (WB) and peripheral blood mononuclear cell (PBMC) cultures derived from venipuncture (VP) and FS blood, to determine whether they respond similarly under culture conditions. The rates of spontaneous- and radiation-induced apoptosis and pro-inflammatory cytokine production were monitored over 72h in each of four culture conditions. In non-irradiated WB cultures, the spontaneous rate of apoptosis was significantly lower in cultures from FS-derived blood than from VP-derived blood. However, FS- and VP-derived cultures responded similarly to radiation-induced apoptosis. PBMC cultures, regardless of the source, were the most responsive to radiation. When the levels of pro-inflammatory cytokines were measured, a significant time-dependent increase in TNF-α, IL-6 and IL-1β production was observed in FS-derived cultures, but not in VP-derived cultures. While VP and FS blood cultures were found to respond similarly to radiation-induced apoptosis, there was a significant difference in the rate of spontaneous apoptosis in non-irradiated WB cultures and in the in situ production of pro-inflammatory cytokines between VP- and FS-derived blood cultures.

Differential Roles of Interleukin-18 (IL-18) and IL-12 for Induction of Gamma Interferon by Staphylococcal Cell Wall Components and Superantigens

The roles of endogenous cytokines induced by either intact staphylococcal microorganisms or staphylococcal exotoxins were examined using human whole-blood cultures. To accomplish this, interleukin-18 binding protein (IL-18BP) and tumor necrosis factor binding protein (TNFbp) were used to neutralize IL-18 and TNF, respectively, whereas an anti-IL-12 monoclonal antibody was used to neutralize IL-12 and the IL-1 receptor antagonist (IL-1Ra) was used to block IL-1 receptors. Heat-killed Staphylococcus epidermidis and Staphylococcus aureus, as well as the staphylococcal superantigens toxic shock syndrome toxin-1 (TSST-1) and staphylococcus enterotoxin B (SEB) induced gamma interferon (IFN-gamma) production. Staphylococcus spp.-induced production of IFN-gamma required the presence of endogenous IL-18, IL-12, and TNF. In contrast, TSST-1-induced IFN-gamma was not significantly reduced in the presence of IL-18BP, anti-IL-12 antibodies, IL-1Ra, or anti-TNFbp. SEB-induced IFN-gamma was significantly inhibited only by anti-IL-12 antibodies, indicating that endogenous IL-18, IL-1, and TNF are not required for SEB-induced IFN-gamma. In conclusion, the mechanisms of IFN-gamma stimulation by intact staphylococcal microorganisms and by exotoxins differ, and this is likely due to the different receptors which are triggered on the cell membranes. In contrast to its role in the interactions between staphylococci and host cells, IL-18 does not appear to play a major role in superantigen-induced IFN-gamma.

Differential cytokine mRNA expression in swine whole blood and peripheral blood mononuclear cell cultures

The kinetics of interleukin-2 (IL-2), IL-6, IL-8 and IL-10 gene expression in concanavalin A (Con A)-activated whole blood (WB) and peripheral blood mononuclear cell (PBMC) cultures were examined using reverse transcriptase-polymerase chain reaction (RT-PCR). Unstimulated PBMC or WB cultures failed to show increases in basal cytokine PCR amplicon levels for any cytokine examined. PBMC cultures demonstrated peak expression of IL-2, IL-6, IL-8 and IL-10 mRNA levels at 12, 24, 24 and 6 h, respectively. WB cultures exhibited peak IL-2, IL-6, IL-8 and IL-10 mRNA levels at 24, 12, 6 and 24 h, respectively. PBMC cultures consistently exhibited higher levels of IL-2 mRNA at all times examined than did WB cultures. WB cultures consistently had higher levels of IL-6 mRNA than PBMC cultures. IL-8 and IL-10 protein levels in PBMC cultures were first detected 12 h after stimulation and continued to increase in concentration through 48 h. In WB cultures, IL-8 and IL-10 protein levels were first noted at 12 and 6 h, respectively. WB culture IL-8 and IL-10 levels quickly reached equilibrium after being detected and remained at levels lower than those noted in PBMC cultures. These results show WB cultures represent an approach with reduced cost and time when compared to traditional cell culture and isolation methods. It may also produce an in vitro test system that more closely resembles in vivo conditions.

Trans-stilbene oxide-induced sister chromatid exchange in cultured human lymphocytes: influence of GSTM1 and GSTT1 genotypes.

About 50% and 15% of Caucasians lack the glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) genes and the corresponding enzyme activity, respectively. Both of these polymorphisms have been shown to affect the genotoxicity of some epoxides in cultured human lymphocytes. Especially GSTT1 appears to be important in whole-blood cultures, probably because GSTT1 activity is high in erythrocytes. The in vitro genotoxicity of trans-stilbene oxide (TSO), a model substrate for GSTM1, has been shown to depend on individual GSTM1 activity. The potential role of GSTM1 genotype, and the possible interference of GSTT1 genotype, has not previously been examined in this context. We have studied TSO-induced sister chromatid exchanges (SCEs) in 72 h whole-blood lymphocyte cultures from 24 healthy human donors, representing different combinations of GSTM1 and GSTT1 positive and null genotypes. TSO clearly increased SCEs in cultures of all donors. The mean number of SCEs per cell induced by 75 and 150 microM TSO was, respectively, 1.5- and 1.3-times higher in cultures of GSTM1 null than GSTM1 positive donors. In another experiment, GSTM1 null individuals showed, in comparison with GSTM1 positive subjects, a 1.8-fold SCE induction by 50 microM TSO. GSTT1 genotype did not have an unequivocal effect. Our findings suggest that the lack of the GSTM1 gene, resulting in reduced detoxification capacity, increases individual sensitivity to the genotoxic effects of TSO.

The synthesis of Rantes, G‐CSF, IL‐4, IL‐5, IL‐6, IL‐12 and IL‐13 in human whole‐blood cultures is modulated by an extract from Eleutherococcus senticosus L. roots

An ethanol extract derived from the roots of Eleutherococcus senticosus was found to influence markedly the cytokine synthesis of activated whole blood cultures of ten healthy volunteers. Whereas the synthesis of Rantes was increased over a wide range of concentrations, the release of IL-4, IL-5 and IL-12 was significantly inhibited. An inhibition at higher concentrations, switching to a stimulation at lower doses of the extract was seen with G-CSF, IL-6 and IL-13. From these particular immuno-pharmacological effects of Eleutherococcus senticosus we suggest this herbal preparation possesses immuno-modulatory potency, rather than just being immuno-suppressive or -stimulating.

Hereditary predisposition to low interleukin-10 production in children with extended oligoarticular juvenile idiopathic arthritis.

To determine whether children with extended oligoarticular juvenile idiopathic arthritis (JIA) produce less of the anti-inflammatory cytokine interleukin-10 (IL-10) than those with persistent oligoarticular JIA. We measured IL-10 production in the parents of children with oligoarticular or extended oligoarticular JIA, from whole-blood cultures stimulated with lipopolysaccharide. IL-10 production was lower in the parents of children with extended oligoarticular JIA compared with those of children with oligoarticular JIA (P=0.034). There was an increase in the percentage of ATA-containing genotypes (i.e. genotypes ATA/ATA, ATA/ACC or ATA/GCC) in the parents of children with extended oligoarticular JIA compared with healthy controls (P<0.02) but not in the parents of children with oligoarticular JIA. As approximately 84% of the variation in IL-10 production is thought to be genetically regulated, these results suggest that stimulated IL-10 production would be lower in children with extended oligoarticular JIA. Because IL-10 is an anti-inflammatory cytokine, this may partly explain why this group of children has more severe disease.

Cell-mediated immune response to tuberculosis antigens: comparison of skin testing and measurement of in vitro gamma interferon production in whole-blood culture.

Although delayed-type hypersensitivity skin testing with tuberculin purified protein derivative (PPD) is the standard for tuberculosis screening, its variability suggests the need for a more sensitive, noninvasive test. An in vitro whole-blood assay has been proposed as an alternative. Using health care worker volunteers, we confirmed the correlation between PPD skin test (PPD-ST) results (positive, induration of >15 mm) and a standardized gamma interferon (IFN-gamma) assay, QuantiFERON-TB (Q-IFN), manufactured by CSL Biosciences in Australia, and we evaluated Mycobacterium tuberculosis culture subfractions as potential substitutes for PPD. Twenty healthy volunteers with positive PPD-ST results and 20 PPD-ST-negative controls were enrolled. Whole blood was cultured with human PPD antigens (HuPPD), Mycobacterium avium complex (MAC) PPD, phytohemagglutinin (PHA), and four M. tuberculosis culture subfractions: low-molecular-weight culture, filtrate, culture filtrate without lipoarabinomannan, soluble cell wall proteins, and cytosolic proteins, all developed from M. tuberculosis strain H(37)RV. Secretion of IFN-gamma (expressed as international units per milliliter) was measured by an enzyme immunoassay. The PPD or subculture fraction response as a percentage of the PHA response was used to determine positivity. Sixteen of 20 PPD-ST-positive individuals were classified as M. tuberculosis positive by Q-IFN, and 1 was classified as MAC positive. Sixteen of 20 PPD-ST-negative individuals were M. tuberculosis negative by Q-IFN, 2 were MAC positive, and 2 were M. tuberculosis positive. The tuberculosis culture subfractions stimulated IFN-gamma production in PPD-ST-positive volunteers, and significant differences could be seen between the two PPD-ST groups with all subfractions except soluble cell wall protein; however, the response was variable and no better than the Q-IFN PPD. The agreement between the Q-IFN test and the PPD-ST was good (Cohen's kappa = 0.73). The Q-IFN assay can be a useful tool in further studies of immune responses to M. tuberculosis antigens.

Influence of AFP, CEA and PSA on the in vitro Production of Cytokines

Several studies have demonstrated a decreased cytokine production in patients with cancer. Likewise, there is some evidence showing that tumor markers may play a role in immunoregulation. In this work, we have studied the in vitro production of IL-1β, IL-6 and TNF-α in whole-blood cell cultures of 10 healthy subjects after polyclonal activation with lipopolysaccharide of Salmonella enteridis and phytohemagglutinin in the presence or absence of three markers, AFP, CEA and PSA. Each sample was incubated for 48 h at 37°C in a humidified atmosphere of 5% CO₂. Subsequently, cytokine levels in the supernatant were determined. AFP did not significantly affect the production of the three cytokines compared to the basal value obtained on adding PBS. In contrast, CEA significantly increased the production of IL-6 (p <0.001) and TNF-α (p = 0.002), while PSA significantly decreased IL-1β (p <0.001), IL-6 (p = 0.031) and TNF-α (p <0.0001) production. These results suggest a possible role of CEA and PSA in the production of these cytokines.

Inflammatory Activity as an Indicator of Water Quality: The use of human whole blood cultures

A rapid whole blood culture (WBC) assay system was developed to monitor the inflammatory potential of water samples collected in the Western Cape, South Africa. Water contaminated with inflammatory substances induced the pro-inflammatory hormone interleukin 6 (IL-6). All water samples collected from the Eerste River, Stellenbosch, induced IL-6 secretion, and the quantity of IL-6 secreted is dependent on the concentration and origin of the sample. the lowest IL-6 inducing activity for river water was obtained for samples collected near the origin of the river. Samples at subsequent points downstream showed an increase in IL-6 inducing activity. Drinking water samples collected from selected towns in the Western Cape showed that there were major differences between the inflammatory potential of the water. of the 15 samples assayed, 7 had low inflammatory activity, 4 had an intermediate inflammatory activity and 4 had high inflammatory activity. the water sources that have a high inflammatory activity may pose a health risk to consumers.

Innate production of interleukin-10 and tumor necrosis factor affects the risk of multiple sclerosis

Multiple sclerosis (MS) typically presents with a relapsing-remitting onset. This can be distinguished from primary progressive MS. Typical MS is characterized by a profound inflammatory reaction in which anti-inflammatory cytokine interleukin-10 (IL-10) and pro-inflammatory cytokine tumor necrosis factor (TNF) may play a pivotal role. We tested the hypothesis that patients with MS have a distinct innate cytokine production that contributes to the susceptibility for and outcome of MS. The innate cytokine production of patients was estimated as the average production of cytokines in lipopolysaccharide -stimulated whole-blood cultures of 2 to 5 first-degree healthy family members. A total of 126 family members of 50 patients with typical MS, 61 family members of 25 patients with primary progressive MS, and 129 control subjects of 54 families were enrolled in this study. We found that members of families with low IL-10 and high TNF production had a fourfold increased risk of developing typical MS compared with members of families with high IL-10 and low TNF production. Patients with MS were eightfold more likely to develop typical MS than primary progressive MS when they belonged to families with low IL-10 and high TNF production. The presence of human leukocyte antigen–DR2 was associated with MS but not with TNF production. This study shows that typical MS is associated with an innate pro-inflammatory cytokine profile in contrast to primary progressive MS. Ann Neurol 2000;48:641–646

Innate production of interleukin-10 and tumor necrosis factor affects the risk of multiple sclerosis.

Multiple sclerosis (MS) typically presents with a relapsing-remitting onset. This can be distinguished from primary progressive MS. Typical MS is characterized by a profound inflammatory reaction in which anti-inflammatory cytokine interleukin-10 (IL-10) and pro-inflammatory cytokine tumor necrosis factor (TNF) may play a pivotal role. We tested the hypothesis that patients with MS have a distinct innate cytokine production that contributes to the susceptibility for and outcome of MS. The innate cytokine production of patients was estimated as the average production of cytokines in lipopolysaccharide -stimulated whole-blood cultures of 2 to 5 first-degree healthy family members. A total of 126 family members of 50 patients with typical MS, 61 family members of 25 patients with primary progressive MS, and 129 control subjects of 54 families were enrolled in this study. We found that members of families with low IL-10 and high TNF production had a fourfold increased risk of developing typical MS compared with members of families with high IL-10 and low TNF production. Patients with MS were eightfold more likely to develop typical MS than primary progressive MS when they belonged to families with low IL-10 and high TNF production. The presence of human leukocyte antigen-DR2 was associated with MS but not with TNF production. This study shows that typical MS is associated with an innate pro-inflammatory cytokine profile in contrast to primary progressive MS.