Autologous Platelet-Rich Plasma (PRP) Efficacy on Endometrial Thickness and Infertility: A Single-Centre Experience from Romania

(1) Background: During IVF (in vitro fertilization), a proper endometrium thickness is one of the most difficult parameters to achieve and one of the most important prognostic factors of the success rate. One major problem is the high cancelation percentage in frozen embryo transfer cycles. The focus on the adjuvant methods for improving endometrium thickness is an on-going subject of interest. (2) Methods: This prospective single-arm self-control study was conducted in an IVF centre in Oradea, Romania. The patients were divided into two groups. The control group included 51 patients with at least one attempt to transfer a good-quality blastocyst, but the endometrial thickness did not surpass 7 mm under standard endometrial preparation protocol with oestradiol and with adjuvant therapy (other than PRP, such as aspirin, vitamin C, and vitamin E), and the study group included the same 51 patients that had the embryo transfer performed under the same standard endometrial preparation protocol with oestradiol preparation protocol and intrauterine PRP infusion. (3) Results: In our study, the PRP treatment had a positive impact on the parameters that were followed for the evaluation of the success rate of the embryo transfer procedure. The endometrial thickness (an increase in endometrial thickness by 0.6 mm after PRP treatment with p = 0.0001) and the clinical pregnancy rate (having a MD ± SD of 0 ± 0.38 before PRP treatment and with an increase to 0.5 ± 0.1 after the PRP treatment, p = 0.0004) were statistically significant (4) Conclusions: PRP has a positive effect in promoting endometrial proliferation, improving embryo implantation rate and clinical pregnancy rate for women with thin endometrium.

The Role of Oxidative Stress in Infertility

(1) Background: Oxidative stress markers in the follicular fluid and serum of the patient with IVF results (number of fertilized oocytes, number of embryos, cumulative pregnancy rate) are important in establishing the causes of infertility. (2) Methods: 42 patients were enrolled in the study over the duration of 24 months and were divided into two groups: the study group divided into the female etiology for infertility as a tubal factor, diminished ovarian reserve, endometriosis, and unexplained infertility, and the control group consisting of the male factor, excluding the sperm donors and with no female factor cause. On the day of ovarian puncture in IVF, follicular fluid and serum were collected from the patients. (3) Results: Malondialdehyde from the follicular fluid was higher in the control group. The total antioxidant capacity in the follicular fluid is positively correlated with the pregnancy rate. There is no statistically significant difference in the oxidative stress markers from serum in both groups. (4) Conclusions: The capacity of the follicular fluid environment to contain the reactive oxygen species (ROS) leads to a higher pregnancy rate in the control group.

Comparison of mechanical properties and host tissue response to OviTex™ and Strattice™ surgical meshes

PURPOSE

This study compared the in vitro/benchtop and in vivo mechanical properties and host biologic response to ovine rumen-derived/polymer mesh hybrid OviTex™ with porcine-derived acellular dermal matrix Strattice™ Firm.

METHODS

OviTex 2S Resorbable (OviTex 2S-R) and Strattice morphology were examined in vitro using histology and scanning electron microscopy; mechanical properties were assessed via tensile test; in vivo host biologic response and explant mechanics were evaluated in a rodent subcutaneous model. Separately, OviTex 1S Permanent (OviTex 1S-P) and Strattice were evaluated in a primate abdominal wall repair model.

RESULTS

OviTex 2S-R demonstrated layer separation, whereas Strattice retained its structural integrity and demonstrated higher maximum load than OviTex 2S-R out-of-package (124.8 ± 11.1 N/cm vs 37.9 ± 5.5 N/cm, p < 0.001), 24 h (55.7 ± 7.4 N/cm vs 5.6 ± 3.8 N/cm, p < 0.001), 48 h (45.3 ± 14.8 N/cm vs 2.8 ± 2.6 N/cm, p = 0.003), and 72 h (29.2 ± 10.5 N/cm vs 3.2 ± 3.1 N/cm, p = 0.006) following collagenase digestion. In rodents, inflammatory cell infiltration was observed between OviTex 2S-R layers, while Strattice induced a minimal inflammatory response. Strattice retained higher maximum load at 3 (46.3 ± 27.4 N/cm vs 9.5 ± 3.2 N/cm, p = 0.041) and 6 weeks (28.6 ± 14.1 N/cm vs 7.0 ± 3.0 N/cm, p = 0.029). In primates, OviTex 1S-P exhibited loss of composite mesh integrity whereas Strattice integrated into host tissue with minimal inflammation and retained higher maximum load at 1 month than OviTex 1S-P (66.8 ± 43.4 N/cm vs 9.6 ± 4.4 N/cm; p = 0.151).

CONCLUSIONS

Strattice retained greater mechanical strength as shown by lower susceptibility to collagenase degradation than OviTex 2S-R in vitro, as well as higher maximum load and improved host biologic response than OviTex 2S-R in rodents and OviTex 1S-P in primates.

Anterior Approach to Hip Arthroplasty with Early Mobilization Key for Reduced Hospital Length of Stay

Background and Objectives: This study aimed to explore the preoperative factors related to early mobilization and length of stay (LOS) after total hip arthroplasty and the benefits of the anterior approach over the traditional lateral approach. Materials and Methods: Every patient benefits from information regarding details of the surgery approach, possible intra, and postoperative complications, post-operator medical care, and steps in the early mobilization protocol. The patient underwent a pre-anesthetic evaluation, was checked for preoperatory vital function, and was reevaluated for mobilization at 6, 12, 24, 36, 48, and 96 h after total hip arthroplasty using the anterior versus lateral approach. Results: The result of the statistical calculations indicates the independent negative risk factors for reaching the mobilization target: age with a coefficient of -0.046, p = 0.0154 and lateral approach with a relative risk of 0.3802 (95% CI: 0.15-0.90), p = 0.0298. Statistical data concerning the length of stay (LOS) showed significant differences in the total days spent in the hospital. The patients who were operated on using the lateral approach presented a higher body mass index than those with the anterior approach, but this difference did not reach the threshold of statistical significance. Conclusions: In our study, patient mobilization is crucial to reduce LOS.

Laser in the Treatment of Atonic Wounds

Atonic wounds represent a major health problem, being frequently encountered in medical practice with consequences that have a negative impact on the patient's daily life as well as their general condition. In this study, a brand laser with a 12-watt probe was used to stimulate patients' wounds. We involved in this study a group of 65 patients, which was compared with a group of 30 patients, the latter not receiving this laser therapy. The data were accumulated from the questionnaire of subjective assessment of the laser impact on patients' condition as well as from the local evolution. We noticed the improvement of the local symptomatology which was found to be more effective in the patients from the study group compared to the reference group. The beneficial and positive effects, mainly on the symptoms but also on the local evolution of atonic wounds, can be observed in our study. We consider that this therapy is of major importance considering the lower costs both from the shortening of hospitalization and the long-term use of various substances. The early reintegration of patients into daily life is an important benefit for them.

Platelets Rich Plasma (PRP) Procedure in the Healing of Atonic Wounds

(1) Background: Patients suffering from chronic wounds report physical, mental, and social consequences due to their existence and care. There is a global need for tissue repair strategies and, in our case, for chronic wound healing. PRP therapy is based on the fact that platelet-derived growth factors (PGF) support the three phases of the wound healing and repair cascade (inflammation, proliferation, and remodeling); (2) Methods: A comparative study was carried out on two groups of patients with atonic wounds totaling a total of 80 cases as follows: a study group in which the PRP procedure was applied and a control group in which the biological product was not injected. The study was carried out in the surgery clinic of the Clinical Hospital C.F. Oradea City; (3) Results: A much faster healing was achieved in the case of patients who benefited from the platelet-rich plasma injection therapy compared to the group of patients in whom this therapy was not used. Three weeks after the plasma injection, a considerable reduction of the wound was evident, with some of the patients presenting with a closed wound; (4) Conclusions: The effect of PRP on the healing of chronic wounds is promising in most cases. A positive effect was also highlighted in terms of reducing treatment costs by considerably reducing the materials used as well as the number of hospitalizations for the same pathology.

Comparative Study of Sperm Selection Techniques for Pregnancy Rates in an Unselected IVF–ICSI Population

(1) Background: Semen analysis is a poor predictor of the fertilization potential of spermatozoa and a male factor may contribute to poor outcomes of the IVF procedure, despite a normal semen analysis. The microfluidic sperm selection (ZyMot-ICSI) is based on the selection of the spermatozoa with the lowest DNA fragmentation rate, but studies do not prove better clinical outcomes after this method. (2) Methods: We conducted a retrospective trial comparing 119 couples that were allocated to the classic gradient centrifugation sperm method (control group), and 120 couples that were allocated with the microfluidic technique being used (study group) at our university-level clinic, to go through IVF. (3) Results: The statistical analysis showed that there is no significant difference between the fertilization rate (study vs. control p = 0.87), but regarding blastocyst rate (study vs. control p = 0.046) and clinical pregnancy (p = 0.049), there is quite a significant statistical difference. Microfluidic preparation of spermatozoa seems to improve the results and it may be utilized more broadly for ICSI, and could also improve the workflow in standard IVF, decrease intervention by laboratory personnel and provide more consistent incubation conditions. (4) Conclusions: The patients that had the sperm preparation for ICSI with the microfluidic sperm selection had slightly better results compared with the gradient centrifugation selection.

Anaplastic Lymphoma Kinase (ALK) Overexpression in Lung Cancer Biopsies - An 18 month study in north western Romania

Lung cancer is the first cause of death worldwide of oncological patients. Most of them are non-small cell lung cancer (NSCLC) and many of them are characterized by different molecular markers that allow the development of personalized treatments. Epithelial growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) are the most frequently tested genes in lung adenocarcinoma and other lung carcinomas with glandular component. The aim of our study is to evaluate the distribution of ALK gene mutation in lung cancer patient from North West part of Romania. We analysed a number of 289 lung biopsies along 18 months. The samples have been incubated with monoclonal ALK antibodies (clone D5F3), according to the manufacturer�s instruction. The interpretation guide provided by manufacturer was used to distinguish the positives vs negative cases. In our study from a total number of 289 lung biopsies, 196 cases were carcinomas. 57.65 % from the total number of lung cancers were adenocarcinomas. A total number of 79 cases have been analysed for ALK gene supra expression. 5.08 % of adenocarcinomas were positive for ALK, but the mean age for this population is higher comparing with the data from other studies.

6-(2,3-Dichlorodiphenyl)-1,2,4-Triazine-3,5-Diamine Use in Pregnancy and Body Stalk Anomaly- A Possible Association?

Body Stalk Anomaly is a rare malformation syndrome characterized by anterior abdominal wall defect, kyphoscoliosis, limb reduction, rudimentary umbilical cord, craniofacial defects and anomalies of the chest wall. The association between antiepileptic drugs, such as Lamotrigine [6-(2,3-dichlorophenyl)- 1,2,4-triazine-3,5-diamine], and the development of such malformation have been studied for many years. Many studies can be found regarding the teratogenic potential of Lamotrigine, but they have contradictory results. We present the case of a 34-year old pregnant, caucasian woman, known with acquired epilepsy due to neurocysticercosis for which she is under treatment with Lamotrigine 400mg/day. The patient was examined at 12 weeks of gestational age, when the ultrasound images showed a large defect in the fetal abdominal wall: eviscerated liver and bowel outside the coelomic cavity, kyphoscoliosis, a short umbilical cord, nuchal translucency 2.8mm, mandibular retrognathism. Based upon the aforementioned ultrasound findings we considered the diagnosis to be Body Stalk Anomaly and recommended a medical abortion. Embryological remainings were sent to pathology and genetic department revealing Turner Syndrome. We consider important to detect typical features of the anomaly in the first trimester and distinguish it from other abdominal defects like omphalocele and gastroschisis, since the conditions imply different management. Another important issue is to be aware about the treatment with Lamotrigine.

CONTINUOUS REPOPULATION OF LYMPHOCYTE SUBSETS IN TRANSPLANTED MYCOBACTERIAL GRANULOMAS

Granulomas are the interface between host and mycobacteria, and are crucial for the surivival of both species. While macrophages are the main cellular component of these lesions, different lymphocyte subpopulations within the lesions also play important roles. Lymphocytes are continuously recruited into these inflammatory lesions via local vessels to replace cells that are either dying or leaving; however, their rate of replacement is not known. Using a model of granuloma transplantation and fluorescently labeled cellular compartments we report that, depending on the subpopulation, 10-80%, of cells in the granuloma are replaced within one week after transplantation. CD4(+) T cells specific for Mycobacterium antigen entered transplanted granulomas at a higher frequency than Foxp3(+) CD4(+) T cells by one week. Interestingly, a small number of T lymphocytes migrated out of the granuloma to secondary lymphoid organs. The mechanisms that define the differences in recruitment and efflux behind each subpopulation requires further studies. Ultimately, a better understanding of lymphoid traffic may provide new ways to modulate, regulate, and treat granulomatous diseases.

Transfection of HEK cells via DNA-loaded PLGA and P(FASA) nanospheres

HEK cells were transfected with the GFP gene using various vectors: naked DNA, lipofectamine, and both PLGA and P(FASA) plasmid-loaded nanospheres. All methods were assessed alone and with the use of chloroquine, a lysosomal enzyme inhibitor. Transfection efficiencies were determined and compared at various times post-incubation using a fluorescence standard curve. Neither naked DNA alone nor naked DNA and chloroquine were capable of transfecting cells. No differences were evident between lipofectamine with chloroquine and lipofectamine alone which transfected cells with a constant increase in efficiency up to 2 weeks. While transfection was not feasible with polymeric nanospheres alone, the addition of chloroquine allowed DNA released from nanospheres within cells to escape endosomal degradation and transfect the cells. The increase in transfection efficiency via nanospheres over time was exponential up to 1 week, as compared to the constant rate seen for the bolus-type administration of lipofectamine, indicating that nanospheres delivered DNA to the cells by a controlled release mechanism. Additionally, the effective dose delivered to cells via nanospheres was approximately 25% that of lipofectamine, indicating that transfection via PLGA and P(FASA) nanospheres might actually be more efficient.

Effect of protein molecular weight on release from micron-sized PLGA microspheres

This study investigates the effect of protein molecular weight on release kinetics from polymeric microspheres (1-3 microm). Proteins were encapsulated at high and low loadings in poly(lactic-co-glycolic acid) (PLGA) by a phase inversion technique. Mechanism of release from this type of microsphere appeared to be dependent on protein molecular weight for microspheres with low loadings (0.5-1.6%), while independent of protein molecular weight for microspheres with high loadings (4.8-6.9%). At low loadings, release of larger proteins was dependent on diffusion through pores for the duration of the study, while smaller proteins seemed to depend on diffusion through pores initially and on degradation at later times. Following an initial diffusion phase from low loaded microspheres, lysozyme and carbonic anhydrase, the two smallest proteins, exhibited lag phases with curtailed protein release followed by a phase of increased protein release between 4 and 8 weeks, a phenomenon not evident for larger proteins. It appears that by 8 weeks, PLGA had degraded enough to allow additional release of smaller proteins which were entrapped efficiently within the microspheres. Higher loaded microspheres, which have more interconnecting channels, did not exhibit the pronounced shift from diffusion-based to polymer degradation-based release seen with the lower loaded microspheres. Interestingly, microspheres encapsulating large proteins maintained sustained release rates for 56 days.

Inhibition of antigen-specific T cell trafficking into the central nervous system via blocking PECAM1/CD31 molecule

Trafficking of antigen-specific T cells into the central nervous system (CNS) is an important initiating step in inflammation in the brain. In spite of the extensive knowledge about the role of adhesion molecules in T cell migration across peripheral vessels, the mechanism of the entry of antigen-specific T cells into the CNS is not known. This work was designed to study the regulatory roles of adhesion molecules in antigen-specific T cell migration into the CNS. Antigen-specific T cells were tracked in an in vivo migration assay using T cell receptor (TCR) transgenic mice having 95% of T cells specific for a defined antigen. pigeon cytochrome c (PCC). TCR transgenic mice were cannulated intraventricularly (IVT) for PCC antigen infusion and cerebrospinal fluid (CSF) sampling. Upon PCC infusion into the CNS, the number of alpha/beta TCR+ Vbeta3+ Mac1- cells in the CSF was characterized in the presence or absence of anti-adhesion molecule reagents. We found that antibodies against VCAM-1 (CD106), VLA-4 (CD49d/CD29), ICAM-1 (CD54), and LFA-1 (CD11a/CD18) did not influence the increased number of antigen-specific T cells in the CSF However, upon intravenous (i.v.) injection, anti-PECAM-1 (CD31) antibody or PECAM-Ig chimeric molecule inhibited the trafficking of alpha/beta TCR+ Vbeta3+ Mac1- cells into the CNS. The expression of PECAM-1 (CD31) was also up-regulated on antigen-specific T cells in a time-dependent manner in vitro upon antigenic stimulation. The antigen-induced activation of T cells in vivo was measured by CD44 and LFA-1 expression and found to be comparable between mPECAMIg-treated mice and wild-type serum control-treated groups. This indicates that CD31 inhibition of antigen-specific T cell accumulation in the CNS is probably not due to a functional inhibition of these cells. Finally, adoptive transfer of CFSE-labeled AND transgenic cells into naïve animals resulted in the accumulation of these cells in the CNS upon PCC IVT immunization that was also inhibited by mPECAMIg treatment. Hence, PECAM-1 (CD31) might play an important role in regulating antigen-specific T cells trafficking in CNS inflammatory diseases.

Mycobacterium bovis strain bacillus Calmette-Guérin-induced liver granulomas contain a diverse TCR repertoire, but a monoclonal T cell population is sufficient for protective granuloma formation

Granuloma formation is a form of delayed-type hypersensitivity requiring CD4(+) T cells. Granulomas control the growth and dissemination of pathogens, preventing host inflammation from harming surrounding tissues. Using a murine model of Mycobacterium bovis strain bacillus Calmette-Guérin (BCG) infection we studied the extent of T cell heterogeneity present in liver granulomas. We demonstrate that the TCR repertoire of granuloma-infiltrating T cells is very diverse even at the single-granuloma level, suggesting that before granuloma closure, a large number of different T cells are recruited to the lesion. At the same time, the TCR repertoire is selected, because AND TCR transgenic T cells (Valpha11/Vbeta3 anti-pigeon cytochrome c) are preferentially excluded from granulomas of BCG-infected AND mice, and cells expressing secondary endemic Vbeta-chains are enriched among AND cells homing to granulomas. Next, we addressed whether TCR heterogeneity is required for effective granuloma formation. We infected 5CC7/recombinase-activating gene 2(-/-) mice with recombinant BCG that express pigeon cytochrome c peptide in a mycobacterial 19-kDa bacterial surface lipoprotein. A CD4(+) T cell with a single specificity in the absence of CD8(+) T cells is sufficient to form granulomas and adequately control bacteria. Our study shows that expanded monoclonal T cell populations can be protective in mycobacterial infection.

Mycobacterium bovis BCG-induced granuloma formation depends on gamma interferon and CD40 ligand but does not require CD28

Progressive granuloma formation is a hallmark of chronic mycobacterial infection. Granulomas are localized, protective inflammatory reactions initiated by CD4+ T cells, which contribute to control of bacterial growth and blockade of bacterial dissemination. In order to understand the costimulatory requirements that allow CD4+ T cells to directly or indirectly induce granulomas, we studied granuloma formation after 6 weeks in Mycobacterium bovis BCG-infected CD28- and CD40 ligand (CD40L)-deficient mice and compared it to granuloma formation in infected wild-type inbred mice and infected cytokine-deficient mice. We characterized granulomas morphologically in liver sections, analyzed granuloma infiltrating cells by flow cytometry, and measured cytokine production by cultured granuloma cells. CD28-deficient mice have no defect at the local inflammatory site, inasmuch as they form protective granulomas and control bacterial growth. However, there are fewer activated T cells in the spleen compared to infected wild-type animals, and quantitative differences in the cellular composition of the granuloma are observed by flow cytometry. In CD40L-deficient mice, the granuloma phenotype is very similar to the phenotype in gamma interferon (IFN-gamma)-deficient mice. Both IFN-gamma-deficient and CD40L-deficient mice form granulomas which prevent bacterial dissemination, but control of bacterial growth is significantly impaired. The relative proportion of CD4+ T cells in granulomas from both CD28(-/-) and CD40L(-/-) mice is significantly decreased compared with wild-type animals. Both models demonstrate that the phenotype and activation stage of systemic T cells do not always correlate with the phenotype and activation stage of the localized granulomatous response.

Interleukin-6 promotes post-traumatic healing in the central nervous system

The central nervous system (CNS) is an immune-privileged site where the role of immune cells and mediators in traumatic brain injury is poorly understood. Previously we have demonstrated that interleukin (IL)-6, a cytokine that acts on a wide range of tissues influencing cell growth and differentiation, is an agonist for vascular endothelial growth factor (VEGF), in in vitro vascularization assays for brain microvessel endothelial cells. In this present work we focus on the role of IL-6 in promoting tissue repair in the CNS in vivo. An aseptic cerebral injury (ACI) was created in the right parietal cortex, using both wild type (C57Bl/6J) and IL-6-deficient (C57Bl/6J-IL-6-/-) mice to study the consequences of the absence of IL-6 on the pathology of brain injuries. We monitored the immediate, early, and late responses to this traumatic injury by characterizing several histologic features in the CNS at days 1, 4, 7 and 14 following injury. Acellular necrosis, cellular infiltration, and re-vascularization were characterized in the injured tissues, and each of these histologic features was individually graded and totaled to assign a healing index. IL-6-deficient mice were found to have a comparatively slower rate of recovery and healing. Furthermore, fluorescein isothiocyanate (FITC)-dextran intravenous injection demonstrated leaky vessels in IL-6-deficient but not in wild type animals following ACI. Additionally, chronic expression of IL-6 in the CNS using transgenic GFAP-IL-6 mice resulted in more rapid healing following ACI. The accelerated tissue repair in GFAP-IL-6 transgenic animals is primarily due to extensive re-vascularization as detected by endothelial cell markers. Combined, this data suggests an important role of IL-6 in tissue repair processes following traumatic injury in the CNS.

Antigen-specific T cell trafficking into the central nervous system

The initiation step of cell-mediated immune responses in the central nervous system (CNS) involves the trafficking of the antigen-specific T cells into the brain. To study this trafficking, we developed an in vivo system for studying antigen-specific responses in the CNS. In this assay, T cell receptor (TCR) transgenic mice having 95% of T cells specific for a defined antigen-pigeon cytochrome c (PCC) were cannulated intraventricularly for PCC antigen infusion and cerebrospinal fluid (CSF) sampling. Upon PCC infusion into the CNS, the number of alpha/beta TCR(+) Vbeta3(+) Mac1(-) cells in the CSF was characterized. We found that infusion of antigen into the CSF induced an increased number of antigen-specific T cells in the CNS and activation of antigen-specific T cells in the peripheral blood. Hence, the drainage of CNS antigen into the periphery might play an important role in sustaining autoimmune reactivity in CNS inflammatory diseases.

Interleukin 6 promotes vasculogenesis of murine brain microvessel endothelial cells

Interleukin 6 (IL-6) is a cytokine that acts on a wide range of tissues influencing cell growth and differentiation. Here we show that IL-6 plays a role in the early vascular development (vasculogenesis) in the central nervous system (CNS). We report that IL-6 induces the proliferation of brain microvascular endothelial cells in vitro. Furthermore, IL-6 significantly accelerates the formation of tube-like structures by these cells in Matrigel basement matrix. Moreover, IL-6 mRNA is expressed in vivo in two physiological conditions in which vascularization in the CNS is important: (1) during normal brain development, (2) during the healing process of a traumatic brain injury. Expression of IL-6 mRNA coincides with the expression of vascular endothelial growth factor (VEGF) mRNA in the developing brain with decreasing expression following birth. However, IL-6 mRNA can be detected in the healing adult murine brain tissue by in situ hybridization coinciding with the period of intense tissue reorganization. The transient upregulation of IL-6 mRNA during normal brain development and at brain injury site and the effect of IL-6 on in vitro vasculogenesis suggest that IL-6 may play a role in normal physiology of vascularization in the CNS.

H1 histamine receptor antagonist inhibits constitutive growth of Jurkat T cells and antigen-specific proliferation of ovalbumin-specific murine T cells

Histamine is produced from histidine by histidine decarboxylase (HDC) in many cells including normal and malignant lymphocytes. We examined the expression of HDC and the effect of histamine receptor antagonists on the proliferation of a human T cell line, Jurkat and on antigen-driven proliferation of lymphocytes from ovalbumin-immunized mice. Our results demonstrate that HDC is inducible in Jurkat cells by anti-CD3. The H1 receptor antagonist triprolidine dose dependently inhibits proliferation of both Jurkat cells and ovalbumin-stimulated murine lymphocytes, while the H2 antagonist ranitidine was ineffective. Alpha-fluoro-methyl-histidine blocking HDC activity did not inhibit the T cell proliferation, suggesting an existing pool of histamine in T cells.

Plasticity of immune responses suppressing parasitemia during acute Plasmodium chabaudi malaria

gammadelta T cells have a crucial role in cell-mediated immunity (CMI) against P. chabaudi malaria, but delta-chain knockout (KO) (deltao/o) mice and mice depleted of gammadelta T cells with mAb cure this infection. To address the question of why mice deficient in gammadelta T cells resolve P. chabaudi infections, we immunized deltao/o mice by infection with viable blood-stage parasites. Sera from infection-immunized mice were tested for their ability to protect JHo/o, deltao/o double KO mice passively against P. chabaudi challenge infection. The onset of parasitemia was significantly delayed in mice receiving immune sera, compared with saline or uninfected serum controls. Immune sera were then fractionated into Ig-rich and Ig-depleted fractions by HPLC on a protein G column. Double KO mice were passively immunized with either fraction and challenged with P. chabaudi. The onset of parasitemia was significantly delayed in recipients of the Ig-rich fraction compared with recipients of the Ig-poor fraction of immune sera. We conclude that deltao/o mice, which are unable to activate CMI against the parasite, suppress P. chabaudi infection by a redundant Ab-mediated process.

A regulatory role for Fc gamma receptors (CD16 and CD32) in hematopoiesis

Progenitor cells of the T- and B-lineages in mice express (CD32) and Fc gamma RIII (CD16) but as the developing lymphocytes begin to express clonal antigen receptors, CD16 and CD32 are downregulated in T-cells, and CD16 is downregulated in B-cells. Considering that counter-receptors for Fc gamma R occur on thymic and bone marrow stromal cells, the possibility exists that Fc gamma R might participate in some aspect of T- and B-lineage development prior to the stage of antigen receptor expression. Previous studies provided evidence that Fc gamma R can influence murine T-lineage development. In the present studies we found that anti-Fc gamma RII/III mAb accelerated B-lineage development in bone marrow cultures from normal mice, but not in cultures from CD16-/- or CD32-/- mice. Similar results were observed when FACS-purified B-progenitor cells were co-cultured with BMS2, a bone marrow stromal cell line. Fresh bone marrow from CD32-/- mice contained about two-fold more B-lineage cells compared to bone marrow from normal or CD16-/- mice. These studies indicate that the Fc gamma R on B-lineage progenitor cells can influence their further development and add to a growing body of evidence that implicates Fc gamma R as regulatory elements in hematopoiesis.

TCR specificity in infection induced granulomas

Granuloma formation is an essential host response to many intracellular pathogens and some particulate antigens. T lymphocytes, especially CD4+ T-cells, are required for the initial formation and ongoing maintenance of the inflammatory response. In the absence of CD4+ T-cells, most infections which normally provoke a granulomatous response are more widely disseminated or lethal since the protective lesions are either malformed or absent. The role of T-cell receptor mediated antigen specificity in infectious states is reviewed with a special emphasis upon recent work on S. mansoni induced granulomas.

A regulatory role for Fcgamma receptors CD16 and CD32 in the development of murine B cells

Early in development, murine B-lineage progenitor cells express two classes of IgG Fc receptors (FcgammaR) designated as FcgammaRII (CD32) and FcgammaRIII (CD16), but mature B lymphocytes only express FcgammaRII (CD32), which functions as an inhibitor of B-cell activation when it is induced to associate with mIgM. The functions of CD16 and CD32 on B-lineage precursor cells have not previously been investigated. To search for FcgammaR functions on developing B-lineage cells, normal murine bone marrow cells were cultured in the presence of 2.4G2, a rat monoclonal antibody that binds to CD16 and CD32, or in the presence of control normal rat IgG, and then the B-lineage compartment was analyzed for effects. Cultures that contained 2.4G2 showed enhanced growth and differentiation of B-lineage cells compared with control cultures. The enhancing effect of 2.4G2 also occurred when fluorescence-activated cell-sorted B-cell precursors (B220(+), sIgM-, HSAhigh, FcgammaR+) from normal bone marrow were cocultured with BMS2, a bone marrow stromal cell line, but not when they were cultured in BMS2-conditioned media. The enhancement of B-lineage development induced by 2.4G2 was CD16-dependent and CD32-dependent, because 2.4G2 did not effect B-lineage growth or differentiation in cultures of bone marrow from mice in which either the gene encoding CD16 or CD32 had been disrupted. Analysis of fresh bone marrow from the CD16 gene-disrupted mice showed normal numbers and distribution of cells within the B-cell compartment, but in CD32 gene-disrupted mice, the B-cell compartment was significantly enlarged. These experiments provide several lines of evidence that the FcgammaR expressed on murine B-cell precursors can influence their growth and differentiation.

Homing of transgenic gammadelta T cells into murine vaginal epithelium

The vaginal epithelium of normal mice contains lymphocytes of fetal thymic origin that express an invariant Vgamma4/Vdelta1 TCR. The apparent lack of other gammadelta TCR species suggests that a selection mechanism might operate to regulate the localization of gammadelta T cells at this anatomical site. Selection might be connected to the Vgamma4/Vdelta1 TCR or to some homing characteristic of the fetal thymic lineage that appears at day 17-18 of embryonic life. In the present studies, we investigated whether transgenic gammadelta cells expressing a TCR species characteristic of the subpopulation of gammadelta T cells found in the blood, spleen and lymph would translocate to the vaginal epithelium. We found that the transgenic Vgamma2 TCR+ cells did accumulate in the vagina of transgenic mice. Furthermore, like normal vaginal gammadelta T cells, the transgenic vaginal gammadelta T cells expressed the phenotype of recently activated memory/effector T cells (CD44(hi), CD62L-, CD45RB(lo), CD69+). Vaginal gammadelta T cells in normal mice do not express the CD2 and CD28 antigens, but both of these markers are present on transgenic vaginal gammadelta T cells. We observed that a small fraction of splenic transgenic gammadelta T cells had the same surface phenotype as the vaginal transgenic gammadelta T cells, raising the possibility that the gammadelta T cells present in the vaginal epithelium of transgenic mice originated from the peripheral lymphoid organs. Data in support of this possibility came from experiments in which co-incubation of splenic transgenic gammadelta T cells with vaginal epithelial cell suspensions induced the vaginal gammadelta phenotype on the splenic gammadelta T cells. The finding of transgenic gammadelta T cells in the vaginal epithelium suggests that homing of gammadelta T cells to this site is not restricted to gammadelta T cells that express the V4/NS1 invariant TCR. Furthermore, these findings imply that retention of gammadelta T cells in the vaginal epithelium of normal mice is affected by a Vgamma4/Vdelta1-specific mechanism. The finding of a significant level of apoptosis in the transgenic vaginal gammadelta T cells, but not in the normal vaginal gammadelta T cells, could reflect that the mechanism of retention of Vgamma4/Vdelta1 + in the vaginal epithelium involves selective survival at the site.

IL-6-deficient mice form granulomas in murine schistosomiasis that exhibit an altered B cell response

IL-6 can play an important role in various biological activities. Using IL-6-deficient, 129 x C57BL/6 mice and normal littermate controls, we studied the role of IL-6 in granulomas of mice infected with schistosomiasis mansoni. Granulomas from IL-6(+/+) mice produced large quantities of IL-6, derived from T, B, and myeloid cells. Yet, IL-6 mutant mice generated normal-appearing granulomas of appropriate size. Multiple-parameter flow cytometric analysis of dispersed granuloma cells revealed no substantial differences. Granuloma cells and splenocytes were cultured in vitro to measure cytokine and immunoglobulin production. Compared to control cells, IL-6(-/-) granuloma cells secreted more IL-4, IL-5, and IL-10. However, splenocytes secreted cytokines comparably. In the IL-6(-/-) state, the granuloma cells released less IgE and substantially more IgM, although IgG1, IgG2a, and IgA secretion remained normal. ELISPOT assay showed that dispersed granuloma cells from IL-6-deficient animals had substantially more IgM-secreting B cells. Thus, schistosome granulomas make IL-6 that is not essential for most aspects of granuloma development. However, IL-6 deficiency results in some disturbance of granuloma cytokine and immunoglobulin expression.

Ontogeny of thymic NK1.1+ cells

Thymic NK1.1+ cells are a recently described lymphocyte subset whose biologic function is not well defined. There is some controversy as to whether thymic NK1.1+ cells mature in a thymic or an extrathymic pathway. In this study, we examined the ontogeny of murine thymic NK1.1+ cells utilizing direct examination of freshly obtained fetal thymi as well as fetal thymi established in organ cultures (FTOC). We found a reproducible peak (5-40%) of NK1.1+ cells, demonstrable in day 15 to 16 freshly obtained fetal thymi, which was markedly decreased by day 17 of gestation; this peak preceded the appearance of the CD4+ CD8+ thymocytes by 12 to 24 h. Reverse-transcriptase PCR analysis of NK1.1 demonstrated its presence as early as day 9 of gestation, thus placing it as one of the earliest lymphocytic genes to be transcribed. Utilizing FTOC, we found that: 1) day 12 fetal thymi contained a progenitor that can differentiate into an NK1.1+ CD4+ CD8+ lymphocyte; 2) NK1.1+ cells dwindle to &lt;5% in FTOC established from day 14 thymi; 3) NK1.1+ cells dominate in FTOC supplemented with IL-2; and 4) most of the NK1.1+ cells seen in FTOC did not express CD3epsilon on their surface, except for the FTOC supplemented with IL-12. These findings suggest that NK1.1+ cells may play an important role in thymic maturation. Moreover, these findings suggest that fetal thymi contain several novel lymphocyte subsets that can be induced to overgrow the normal thymocytes upon exposure to certain cytokines.

Ontogeny of thymic NK1.1+ cells

Thymic NK1.1+ cells are a recently described lymphocyte subset whose biologic function is not well defined. There is some controversy as to whether thymic NK1.1+ cells mature in a thymic or an extrathymic pathway. In this study, we examined the ontogeny of murine thymic NK1.1+ cells utilizing direct examination of freshly obtained fetal thymi as well as fetal thymi established in organ cultures (FTOC). We found a reproducible peak (5-40%) of NK1.1+ cells, demonstrable in day 15 to 16 freshly obtained fetal thymi, which was markedly decreased by day 17 of gestation; this peak preceded the appearance of the CD4+ CD8+ thymocytes by 12 to 24 h. Reverse-transcriptase PCR analysis of NK1.1 demonstrated its presence as early as day 9 of gestation, thus placing it as one of the earliest lymphocytic genes to be transcribed. Utilizing FTOC, we found that: 1) day 12 fetal thymi contained a progenitor that can differentiate into an NK1.1+ CD4+ CD8+ lymphocyte; 2) NK1.1+ cells dwindle to <5% in FTOC established from day 14 thymi; 3) NK1.1+ cells dominate in FTOC supplemented with IL-2; and 4) most of the NK1.1+ cells seen in FTOC did not express CD3epsilon on their surface, except for the FTOC supplemented with IL-12. These findings suggest that NK1.1+ cells may play an important role in thymic maturation. Moreover, these findings suggest that fetal thymi contain several novel lymphocyte subsets that can be induced to overgrow the normal thymocytes upon exposure to certain cytokines.

Fc gammaRII (CD32) is linked to apoptotic pathways in murine granulocyte precursors and mature eosinophils

Murine granulocytes and precursors express low-affinity IgG Fc receptors (Fc gammaR). We investigated the effects of FcyR ligation on the development of eosinophils in cultures of normal murine bone marrow. Eosinophilopoiesis was induced by culture of bone marrow cells in the presence of cytokines (granulocyte-macrophage colony-stimulating factor [GM-CSF], interleukin-3 [IL-3], and IL-5). Addition to the cultures of 2.4G2, a rat monoclonal antibody (mAb) that reacts with Fc gammaRII (CD32) and Fc gammaRIII (CD16), induced granulocyte apoptosis within 24 hours. Granulocytes in cultures that contained 2.4G2 showed chromatin condensation, binding of Annexin-V, and fas induction, and by electron microscopy, apoptosis was most commonly observed in cells of the eosinophil lineage. Since murine granulocytes can express both Fc gammaRII (CD32) and Fc gammaRIII (CD16), we investigated the effect of 2.4G2 on cultures of bone marrow obtained from Fc gammaRIII (CD16) gene-disrupted mice and found that the apoptosis induced with 2.4G2 was CD16-independent. Studies with bone marrow cultures from B6MLR-lpr/lpr and C3H/HEJ-gld/gld mice established that the Fc gammaRII (CD32)-triggered apoptosis was fas-fasL-dependent. When mature eosinophils isolated from hepatic granulomas of Schistosoma mansoni-infected mice were cultured in cytokines in the presence of 2.4G2, the eosinophils underwent apoptosis within 24 hours. These findings identify a previously unknown linkage between Fc gammaR on eosinophils and fas-mediated apoptosis, a connection that could be relevant to mechanisms by which eosinophils mediate tissue injury and antibody-dependent cellular cytotoxicity reactions.

Lack of Fc-epsilon receptors on murine eosinophils: implications for the functional significance of elevated IgE and eosinophils in parasitic infections

Chronic infection with Schistosoma mansoni induces in humans and mice a Th2-dominant immune response in which eosinophils and IgE are conspicuously elevated. Human eosinophils express IgE receptors that participate in an IgE-dependent eosinophil-mediated ADCC reaction against Schistosomula larvae in vitro. To investigate the expression of IgE receptors on murine eosinophils, they were purified (>95% pure by Giemsa-stained cytospin preparations) from liver granulomas of Schistosoma-infected mice. Flow cytometric analysis showed the absence of the low-affinity IgE receptor Fc-epsilon RII (CD23) and Mac-2 and the absence of binding of murine IgE. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of granuloma eosinophil mRNA did not detect transcripts for Fc-epsilon RII or the alpha-chain of the high-affinity IgE receptor Fc-epsilon RI, but did detect transcripts that encode Mac-2 and the low-affinity IgG receptors Fc-gamma RIIb2, Fc-gamma RIII, and the FcR-associated gamma-chain. In vitro stimulation of granuloma eosinophils with interleukin-4 (IL-4) did not induce IgE binding, surface expression of Mac-2, or the transcription of Fc-epsilon receptors (Fc-epsilon RI, Fc-epsilon RII/CD23). To investigate normal murine eosinophils, we cultured normal mouse bone marrow cells with recombinant IL-3, recombinant IL-5, and recombinant granulocyte-macrophage colony-stimulating factor, conditions that promote eosinophil differentiation. Flow cytometric analysis of bone marrow-derived eosinophils failed to detect IgE binding or cell surface expression of Fc-epsilon RII and Mac-2, and RT-PCR analysis of fluorescence-activated cell sorted bone marrow-derived eosinophils failed to detect transcripts that encode Fc-epsilon RI or Fc-epsilon RII. These findings show that, in contrast to human eosinophils, murine eosinophils do not express cell surface receptors that bind IgE. However, because IgG receptors (Fc-gamma RIIb2, Fc-gamma RII) were present on eosinophils purified from granulomas, we investigated whether they might be involved in eosinophil activation. We found that an oxidative burst in eosinophils could be triggered through their IgG receptors.

Gamma delta T cells of the murine vagina: T cell response in vivo in the absence of the expression of CD2 and CD28 molecules

While little is known about their activation requirements and function, the intraepithelial T cells of the murine vagina express TCR complexes in which the antigen recognition components and the signaling components have unusual features. These vaginal T cells express an invariant V gamma 4/V delta 1 TCR and appear to be the only intraepithelial gamma delta T cells that exclusively use FcR gamma chains in their TCR complex. To further characterize the vaginal gamma delta T cells we isolated them from normal mice and from mice injected systemically with an activation-inducing dose of anti-TCR mAb. The isolated gamma delta T cells were examined by flow cytometry for their surface expression of a panel of adhesion, proteins, activation antigens and cellular interaction molecules (CD44, CD62L, CD45RB, LFA-1, CD2 and CD28). The patterns of expression observed indicate that the vaginal gamma delta T cells of normal mice show the phenotype of effector T cells. The adhesion/co-stimulatory molecules CD28 and CD2 were not detected on vaginal gamma delta T cells, an interesting finding since the absence of CD2 from other T cells has been suggested to result in anergy. However, vaginal gamma delta T cells are responsive to TCR-mediated signals since injection of normal mice with pan-anti-TCR antibody or stimulating anti-gamma delta TCR antibody resulted in an increase in cell number and increased expression of transferrin and IL-2 receptors. These results indicate that vaginal gamma delta T cells might utilize other co-stimulatory molecules, if any, in connection with TCR-induced activation and differentiation. While the physiological function of vaginal gamma delta T cells remains unknown, the expression of an invariant V gamma 4/V delta 1 TCR, their exclusive use of gamma chain homodimers in their TCR, and the absence of CD2 and CD28 co-stimulatory molecules are a novel combination of properties that suggests specialized functional properties. Although vaginal gamma delta T cells share some features in common with gamma delta T cells that reside in other epithelial tissues, such as skin and intestine, the present studies provide additional evidence that vaginal gamma delta T cells are a highly specialized and distinct T cell population.

Activation features of intraepithelial gamma delta T-cells of the murine vagina

The epithelium of the murine vagina contains a resident population of gamma delta T-cells that expresses a homogenous Vgamma4/Vdelta1 TCR lacking N-region junctional diversity, implying that these T-cells recognize a very limited array of antigenic structures. The vaginal gamma delta T-cells express a pattern of surface markers characteristic of memory/effector T-cells that have previously been activated. Although vaginal gamma delta T-cells do not express the major costimulatory molecules CD28 and CD2, they do proliferate in response to a systemically delivered anti gamma delta TCR stimulus. Vaginal gamma delta T-cells contain mRNA that encodes the keratinocyte growth factor raising the possibility that these cells play a role in the repair of vaginal epithelium following injury. While the antigen recognized by the vaginal gamma delta TCR is unknown, a model is proposed which attempts to relate some of the unusual phenotypic features of vaginal gamma delta T-cells to the physiological injury and shedding of vaginal epithelium that occurs during the estrous cycle.

The granulomatous response in murine Schistosomiasis mansoni does not switch to Th1 in IL-4-deficient C57BL/6 mice

IL-4 plays an important role in polarizing inflammation toward a Th2 response. It remains uncertain, however, whether IL-4 also serves to prevent expression of Th1 inflammation. Therefore, using a genetically pure C57BL/6 IL-4-deficient mouse, we studied the role of IL-4 in regulating the production of IFN-gamma and Th1 inflammation in the granulomas of mice infected with Schistosoma mansoni. In contrast to normal animals, IL-4 mutant mice generated smaller liver granulomas that contained fewer eosinophils and no mast cells. Collagenase-dispersed granuloma cells were analyzed by flow cytometry and cultured in vitro to measure cytokine and Ig production. Compared with control granuloma cells, IL-4-/- cells secreted only small quantities of IL-5 and IL-10. Also, there was impaired expression of the IL-4-dependent molecules IgE and IgG1 as well as B cell surface class II and CD23. Yet the granulomas of IL-4 -/- animals produced little IFN-gamma, IgG2a, or other molecules associated with Th1 inflammation even after Ag or anti-CD3 stimulation. Splenocytes from IL-4 -/- animals stimulated with schistosome Ag also failed to produce a Th1 response. Our data show that most aspects of the Th2 response in murine schistosomiasis are highly dependent on IL-4 production. But in the absence of IL-4, neither the natural local granulomatous response to schistosome ova nor the systemic response to soluble egg Ag switches to the type 1 phenotype. Thus the production of IL-4 early in the inflammatory response is not the only factor preventing Th1 expression in inflammation.

The granulomatous response in murine Schistosomiasis mansoni does not switch to Th1 in IL-4-deficient C57BL/6 mice

IL-4 plays an important role in polarizing inflammation toward a Th2 response. It remains uncertain, however, whether IL-4 also serves to prevent expression of Th1 inflammation. Therefore, using a genetically pure C57BL/6 IL-4-deficient mouse, we studied the role of IL-4 in regulating the production of IFN-gamma and Th1 inflammation in the granulomas of mice infected with Schistosoma mansoni. In contrast to normal animals, IL-4 mutant mice generated smaller liver granulomas that contained fewer eosinophils and no mast cells. Collagenase-dispersed granuloma cells were analyzed by flow cytometry and cultured in vitro to measure cytokine and Ig production. Compared with control granuloma cells, IL-4-/- cells secreted only small quantities of IL-5 and IL-10. Also, there was impaired expression of the IL-4-dependent molecules IgE and IgG1 as well as B cell surface class II and CD23. Yet the granulomas of IL-4 -/- animals produced little IFN-gamma, IgG2a, or other molecules associated with Th1 inflammation even after Ag or anti-CD3 stimulation. Splenocytes from IL-4 -/- animals stimulated with schistosome Ag also failed to produce a Th1 response. Our data show that most aspects of the Th2 response in murine schistosomiasis are highly dependent on IL-4 production. But in the absence of IL-4, neither the natural local granulomatous response to schistosome ova nor the systemic response to soluble egg Ag switches to the type 1 phenotype. Thus the production of IL-4 early in the inflammatory response is not the only factor preventing Th1 expression in inflammation.

N-Dansyl-N′-ethylthiourea for the fluorometric detection of heavy metal ions

N-Dansyl-N'-ethylthiourea (DET) forms fluorescent chelates with a large number of heavy metal ions. The influence of the pH-value on the luminescence of DET and its metal chelates was investigated. The addition of Cu(II) to DET causes a bathochromic shift of the emission maximum, which is linearly dependent on the Cu(II) concentration. Low detection limits and a wide linear range of detection are achieved by HPLC using RP 18 columns as stationary phase. Also presented are first measurements of fluorescence decay times of the ligand as well as some complexes.

Impaired IgG-dependent anaphylaxis and Arthus reaction in Fc gamma RIII (CD16) deficient mice

The family of receptors for IgG (Fc gamma R) plays an essential role in antibody-mediated effector functions of the immune system. However, the specific contribution of each of the Fc gamma R classes to in vivo immune reactions is still unclear. Here, we demonstrate that mice deficient for the ligand-binding alpha chain of Fc gamma RIII lack NK cell-mediated antibody-dependent cytotoxicity and phagocytosis of IgG1-coated particles by macrophages. Strikingly, these mice lack IgG-mediated mast cell degranulation, are resistant to IgG-dependent passive cutaneous anaphylaxis, and exhibit an impaired Arthus reaction. These results indicate a prominent role for Fc gamma RIII in inflammatory and anaphylactic responses, making this receptor a potential target in immunotherapy.

T cell vasoactive intestinal peptide receptor subtype expression differs between granulomas and spleen of schistosome-infected mice

Granulomas form in the liver and intestines of mice infected with the parasite Schistosoma mansoni. Vasoactive intestinal peptide (VIP) is a neurokine that can modulate aspects of the immune response by acting through receptors within the granuloma. Cloned are two novel VIP receptor (VIPR) mRNAs (VIPR1 and VIPR2) that also bind a second neurokine called pituitary adenylated cyclase-activating polypeptide (PACAP). The objective of this study was to determine if granulomas express either VIPR1 or VIPR2. Using a radioligand-binding assay, it was established that PACAP is as effective as VIP at displacing radiolabeled VIP from splenocytes and granuloma cells, and that most if not all VIPRs in the spleen and granulomas bind PACAP. PCR amplification of reverse transcribed RNA determined that granulomas express both VIPR1 and VIPR2 mRNAs. Gel electrophoresis and nucleotide sequencing confirmed the authenticity of the PCR products. Also, both receptor subtypes were amplified from several granuloma CD4+ T cell lines; yet reverse transcribed RNA from T cell-depleted, dispersed granuloma cells had only VIPR1 RNA. It is notable that reverse transcriptase-PCR detected only VIPR1 in the thymus and spleen, which are organs rich in T lymphocytes. Thus, the granulomas and spleens from mice with schistosomiasis contain cells that display authentic VIP/PACAP receptors. Moreover, these data suggest that T cells in different compartments vary in VIPR subtype expression. VIPR1 and VIPR2 may have different physiologic roles in inflammation.

T cell vasoactive intestinal peptide receptor subtype expression differs between granulomas and spleen of schistosome-infected mice

Granulomas form in the liver and intestines of mice infected with the parasite Schistosoma mansoni. Vasoactive intestinal peptide (VIP) is a neurokine that can modulate aspects of the immune response by acting through receptors within the granuloma. Cloned are two novel VIP receptor (VIPR) mRNAs (VIPR1 and VIPR2) that also bind a second neurokine called pituitary adenylated cyclase-activating polypeptide (PACAP). The objective of this study was to determine if granulomas express either VIPR1 or VIPR2. Using a radioligand-binding assay, it was established that PACAP is as effective as VIP at displacing radiolabeled VIP from splenocytes and granuloma cells, and that most if not all VIPRs in the spleen and granulomas bind PACAP. PCR amplification of reverse transcribed RNA determined that granulomas express both VIPR1 and VIPR2 mRNAs. Gel electrophoresis and nucleotide sequencing confirmed the authenticity of the PCR products. Also, both receptor subtypes were amplified from several granuloma CD4+ T cell lines; yet reverse transcribed RNA from T cell-depleted, dispersed granuloma cells had only VIPR1 RNA. It is notable that reverse transcriptase-PCR detected only VIPR1 in the thymus and spleen, which are organs rich in T lymphocytes. Thus, the granulomas and spleens from mice with schistosomiasis contain cells that display authentic VIP/PACAP receptors. Moreover, these data suggest that T cells in different compartments vary in VIPR subtype expression. VIPR1 and VIPR2 may have different physiologic roles in inflammation.