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N Pejnovic

Publications and source records attributed to N Pejnovic.

7 recordsLinked to original sources
PubMed2001

Human IL-18 receptor and ST2L are stable and selective markers for the respective type 1 and type 2 circulating lymphocytes.

CD4(+) (Th) and CD8(+) (Tc) T and NK lymphocytes can be divided into type 1 and 2 subsets according to their cytokine secretion profile. Studies on the role of lymphocyte subsets in human diseases have been hampered by the lack of stable surface markers to define them. Recently, we reported that ST2L and IL-18R are stably expressed on murine Th2 and Th1 cells, respectively. In this study, we generated Abs to human homologues of ST2L and IL-18R and tested them against Th1/Th2, Tc1/Tc2, and NK1/NK2 lines and PBMCs from healthy individuals. We show for the first time that ST2L and IL-18R are stable selective cell surface markers for human Th2/Tc2/NK2 and Th1/Tc1/NK1 lymphocytes, respectively. We then investigated PBMCs from HIV-infected patients and HIV-negative individuals, to test whether Abs to these two surface markers could be used directly to monitor lymphocyte subset distribution in human diseases. We found a clear Th1 to Th2 shift in the HIV-infected individuals, thus settling a long-standing controversy and include, for the first time, Tc and NK cells as well. Therefore, these cell surface molecules could serve as important determinants of the immune status of human diseases in general, and thereby could be useful for therapeutic monitoring and intervention.

Biomarkers↗
PubMed1999

Recognizing, scoring, and predicting blast injuries.

The aim of this study was to find relevant signs and readily available parameters for the recognition of blast injuries and estimation of their severity. The injury severity, estimated by the Injury Severity Score (ISS), Red Cross Wound Classification (RCWC), and experimentally defined Pathology Scoring System for Blast Injuries (PSS/IS) according to Yelverton and modified for use in humans, was compared with a great number of subjective sensations, clinical signs, parameters of hemodynamic, metabolic, neuroendocrine and immune conditions. On the basis of these data, the confidence of the above-mentioned methods was analyzed in the evaluation of blast injuries. This study included 1303 casualties, wounded by explosive devices and with suspected blast injuries, treated at the Military Medical Academy in Belgrade (MMA) from 1991 to 1994. The patients were examined on admission at the MMA (<18 hours) and during hospitalization (1, 2, 5, and 7 days after wounding). The casualties with confirmed blast injury (n = 665, 51%) had an ISS ranging from 0 to 34 (mean 13) had wounds ranging from G1ST (soft tissue wounds caused by low energy transfer) to G3VF (massive wounds with fractures and injury of vital structures) according to the RCWC, with PSS/IS scores from 2 to 105 (mean 60). Statistically significant correlation was found between ISS and PSS/IS as well as RCWC and PSS/IS. Cytokines (IL-1, TNF|ga) and amino acids responded to a blast injury in similar manner as to gunshot wounds with a greater ISS or more severe RCWC injury type. The subjective sensations in blasted patients (deafness, thoracic pain, vertigo) and mediators, confirmed in previous experimental investigations as important factors in the pathogenesis of blast injuries (TxA2, sulfidopeptide leukotrienes) were relationed only to the PSS/IS.

Adult↗
PubMed1998

Disseminated Bacillus Calmette-Guérin infection in a girl with hyperimmunoglobulin E syndrome.

Disseminated Bacillus Calmette-Guérin infection occurs in few well-defined immunodeficiencies, such as severe combined immunodeficiency, chronic granulomatous disease and paediatric acquired immunodeficiency syndrome. This severe complication of immunization against tuberculosis has been lethal in the majority of children who had primary immunodeficiency. Our patient, a 9-y-old girl with hyperimmunoglobulin E syndrome developed disseminated Bacillus Calmette-Guérin infection in infancy. Patients with hyperimmunoglobulin E syndrome (HIES) are susceptible to serious staphylococcal and fungal infections. Disseminated Bacillus Calmette-Guérin infection has not previously been reported in this rare immunodeficiency.

Adjuvants, Immunologic↗
PubMed1989

Blood-brain barrier permeability changes during acute allergic encephalomyelitis induced in the guinea pig.

Blood-brain barrier permeability to homologous serum 125I-IgG and to D-[3H]mannitol was studied by means of the brain vascular perfusion method in guinea pigs with experimental allergic encephalomyelitis (EAE). EAE was induced with homologous myelin basic protein (MBP) after pretreatment with foreign protein and muramyl dipeptide (MDP). The results suggest a significant comparable increase in IgG blood-to-brain clearance in the parietal cortex, hippocampus, and caudate nucleus, during vascular perfusion of the brains of animals, after 7 and 20 days of EAE. On the other hand, unidirectional transfer of mannitol in the same period of EAE was markedly augmented only in the hippocampus, but no significant changes in the parietal cortex or caudate nucleus were observed. Cerebrospinal fluid (CSF)/serum ratios for IgG and albumin were both significantly increased, suggesting an increase in blood-CSF barrier permeability, but more for albumin than for IgG. The results were confirmed by immunohistochemical determination of the IgG deposits in the brains of EAE animals, during vascular perfusion with unlabeled homologous IgG. An important role of the blood-brain barrier for the central nervous system immunoglobulin homeostasis during EAE is suggested.

Animals↗
PubMedDate not supplied

Disease modifying and immunomodulatory effects of high dose 1 alpha (OH) D3 in rheumatoid arthritis patients.

OBJECTIVE: Vitamin D analogues such as 1 alpha (OH) D3 (alphacalcidiol) have a possible physiological paracrine effect on cell proliferation and differentiation. Experimentally established possibilities to prevent autoimmune diseases suggest that alphacalcidiol may have therapeutic value as an immunomodulatory agent in patients with rheumatoid arthritis. METHODS: We organized a 3-month open-label trial on 19 patients being treated with standard DMARD therapy for acute RA. They were divided into 2 subgroups, those with highly active RA and those with moderately active RA. Their regular drug regimen was maintained during the trial and oral alphacalcidiol 2 micrograms/day was added. Therapy results were evaluated by ESR, CRP, morning stiffness, the Richie index, and the Lee index. Immunomodulatory effects were investigated by measuring lymphocyte proliferation and apoptosis both in the patients and in vitro in 10 nM alphacalcidiol-supplemented culture medium. RESULTS: After 3 months, high dose oral alphacalcidiol therapy showed a positive effect on disease activity in 89% of the patients (45% or 9 pts. with complete remission and 44% or 8 pts. with a satisfactory effect). Only two patients (11%) showed no improvement, but no new symptoms occurred. No side effects were observed. CONCLUSION: These results suggest that alphacalcidiol is a powerful immunomodulatory agent with fairly low hypercalcemic activity. Clinical improvement was strongly correlated with the immunomodulating potential of this agent. We noticed dual effects on lymphocyte proliferation and apoptosis according to the prior cell activation state. Alphacalcidiol could therefore possibly be used as an adjunct therapy with DMARDs in patients with rheumatoid arthritis.

Adjuvants, Immunologic↗
PubMedDate not supplied

Interleukin-1 in vivo modulates trauma-induced immunosuppression.

To elucidate the mechanisms underlying trauma-induced immunosuppression and decreased IL-2 production we evaluated: 1) the effect of trauma on IL-1 production at different time intervals and 2) the effect of IL-1 in vivo administration on immune functions (IL-1 production, IL2 production, NK cell cytotoxicity) in normal and traumatized mice. Experiments were performed on CBA/H mice a) subjected to scald injury (sacrificed 3 h and 6 h later) b) treated with IL-1 in vivo (human recombinant IL-1 beta 100 ng/mouse, sacrificed 21 h and 24 h later) and c) subjected to both IL-1 in vivo treatment and scald (IL-1 was given 18 h before scald, animals were sacrificed 3 h and 6 h after scald i.e. 21 h and 24 h after IL-1 administration). Our results demonstrate that trauma alone increases IL-1 production from 1 h to 24 h after trauma infliction. Recombinant IL-1 given in vivo also induces a significant rise in IL-1 production. When mice were subjected to both trauma and IL-1 in vivo treatment, the rise in IL-1 production was not additive. Trauma induced severe depression of IL-2 production which could not be overcome by in vitro addition of IL-1 to IL-2 producing splenocytes from traumatized mice. In contrast, IL-1 administered in vivo stimulated IL-2 production in normal mice, and when given prior to trauma infliction, it completely abrogated trauma-induced suppression of IL-2 production. The same effect was seen on NK cell cytotoxicity (an IL-2 dependent function).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗