Autologous chondrocyte implantation (ACI) for aged patients: development of the proper cell expansion conditions for possible therapeutic applications

OBJECTIVE

Proliferation and chondrogenic commitment of cultured articular chondrocytes are impaired when cells derive from aged donors. In those subjects the feasibility of cell-based therapies for articular surface repair is reduced. Moreover, the use of serum as medium supplement elicits non-physiological responses in cultured chondrocytes. This study was therefore undertaken to identify the expansion culture conditions needed to sustain growth and chondrogenic commitment of chondrocytes harvested from aged human subjects.

DESIGN

Articular cartilage was obtained from aged (69-75 years) and from young adult subjects (27-35 years). Chondrocytes were isolated and cultured in serum-free (SF) or in serum-supplemented [fetal calf serum (FCS)] conditions. Chondrocytes were expanded in monolayer for five duplications and processed for RNA extraction and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. The differentiation potential was assessed by micromass pellet cultures before and after expansion in either culture medium, or after a prolonged exposure to serum followed by a period in SF condition.

RESULTS

Only SF-cultured chondrocytes reached five duplications within 25-35 days, maintaining the expression of some chondrogenic markers and without altering the levels of active matrix metalloproteinase 3 (MMP-3). Only the pellets derived from SF-expanded cultures positively stained for cartilage matrix deposition. On the contrary, exposure to serum diminished the proliferation capacities, abolished the differentiation potential in the same cells and elicited transcription of the MMP-3 gene. Shifting culture conditions from FCS to SF resumed growth rates but proper extracellular matrix deposition was only partially restored.

CONCLUSIONS

The SF conditions have proven valuable to prime cell proliferation and to sustain proper commitment in chondrocytes from aged patients. This culturing approach may represent a therapeutic chance extendable to a range of patients normally excluded from clinical protocols based on autologous chondrocyte implantation (ACI).

Weekly paclitaxel as first-line chemotherapy in elderly advanced breast cancer patients: a phase II study of the Gruppo Italiano di Oncologia Geriatrica (GIOGer)

BACKGROUND

First-line chemotherapy regimens suitable for elderly advanced breast cancer patients are still not defined.

PATIENTS AND METHODS

Women with stage III or IV breast cancer aged > or =70 years were enrolled in a phase II study aimed to evaluate both activity and toxicity of weekly paclitaxel. Among 46 planned patients, at least 18 responses and not more than seven unacceptable toxic events are required for a favourable conclusion. Paclitaxel 80 mg/m(2) was administered weekly for 3 weeks every 28 days.

RESULTS

Unacceptable toxicity occurred in seven out of 46 patients evaluated for toxicity [15.2%; exact 95% confidence interval (CI) 7.6% to 28.2%] and was represented by one case of febrile neutropenia, one case of severe allergic reaction and five cases of cardiac toxicity. Among 41 patients evaluated for response, a complete response occurred in two (4.9%) patients and a partial response in 20 (48.8%), with an overall response rate of 53.7% (exact 95% CI 38.7% to 67.9%). The median progression-free survival was 9.7 months (95% CI 8.5-18.7) and median survival was 35.8 months (95% CI 19-not defined).

CONCLUSIONS

Weekly paclitaxel is highly active in elderly advanced breast cancer patients. Data on cardiovascular complications, however, indicate the need for a careful monitoring of cardiac function before and during chemotherapy.

BCA-1, A B-cell chemoattractant signal, is constantly expressed in cutaneous lymphoproliferative B-cell disorders

We analysed the immunophenotypic and molecular expression of BCA-1 (B-cell-specific chemokine) and CXCR5 (BCA-1 receptor) in normal skin and different cutaneous lymphoproliferative disorders (cutaneous T-cell lymphoma (CTCL); cutaneous B-cell lymphoma (CBCL); cutaneous B-cell pseudolymphoma (PCBCL)), with the aim of investigating their possible involvement in the pathogenesis of cutaneous B-cell disorders. BCA-1 and CXCR5 were constantly expressed in CBCL and PCBCL, but not in normal skin and CTCL. BCA-1 and CXCR5 were constantly coexpressed by CD22+ B-cells, while CD35+ follicular dendritic cells coexpressed BCA-1 in PCBCL cells only. In low grade CBCL, as compared with high grade CBCL, the intensity of CXCR5 expression on neoplastic CD22+ cells was lower than that of BCA-1. The image analysis of reverse transcriptase-polymerase chain reaction (RT-PCR) products showed a significant quantitative difference between PCBCL/low grade CBCL and high grade CBCL. The above findings, although only observed in a small series of patients, are in keeping with findings in MALT gastric and gastric MALT lymphomas, adding further evidence of the close similarities between CBCL and MALT lymphomas.

Implications of spatial heterogeneity for management of marine protected areas (MPAs): examples from assemblages of rocky coasts in the northwest Mediterranean

Marine protected areas (MPAs) are increasingly used as a management tool to preserve species and habitats. Testing hypotheses about the effectiveness of MPAs is important for their implementation and to identify informative criteria to support management decisions. This study tested the general proposition that MPAs affected assemblages of algae and invertebrates between 0.0 and 0.5 m above the mean low water level of rocky coasts on two islands in the Tuscan Archipelago (northwest Mediterranean). Protection was concentrated mainly on the west coasts of the islands, raising the possibility that neither the full range of assemblages nor the relevant scales of variation were properly represented within MPAs. This motivated the comparison of assemblages on opposite sides of islands (habitats). The effects of MPAs and habitat were assessed with a multifactorial sampling design; hypotheses were tested about differences in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation. The design consisted of three replicate shores for each condition of protected and reference areas on the west side of each island and three unprotected shores on the eastern side. Assemblages were sampled independently four times on each island between June 1999 and January 2001. At each time of sampling two sites were selected randomly at each of two tidal heights to represent midshore and lowshore assemblages on each shore. Estimates of abundance were obtained using non-destructive sampling methods from five replicate 20x20 cm quadrats at each site. Results indicated differences among habitats in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation at the scale of shores. Most of these patterns were inconsistent with the predicted effect of management through MPAs. The data suggest that designation of MPAs in the Tuscan Archipelago should proceed through management of multiple shores and types of habitat selected to guarantee protection to a representative sample of assemblages and to the processes responsible for maintenance of spatial patchiness at different scales. This study also shows that considerations of spatial heterogeneity are important to underpin management decisions about the number, size and location of MPAs.

Evaluation of different inhaled combination therapies (EDICT): a randomised, double-blind comparison of Seretide (50/250 microg bd Diskus vs. formoterol (12 microg bd) and budesonide (800 microg bd) given concurrently (both via Turbuhaler) in patients with moderate-to-severe asthma

The aim of this study was to compare the efficacy safety and cost of Seretide (salmeterol/fluticasone propionate (Salm/FP), 50/250 microg bd) via Diskus with formoterol (Form; 12 microg bd) and budesonide (Bud; 800 microg bd) given concurrently (Form+Bud) via Turbuhaler in patients with moderate-to-severe asthma who were uncontrolled on existing corticosteroid therapy. The study used a randomised, double-blind, double-dummy, parallel-group design, consisting of a 2-week run-in period on current corticosteroid therapy (1000-1600 microg/day of BDP or equivalent) and a 12-week treatment period. Symptomatic patients (n = 428) with FEV1 of 50-85% predicted and increased symptom scores or reliever use during run-in were randomly allocated to receive either Salm/FP (50/250 microg bd) via a single Diskus inhaleror Form+Bud (12+800 microg bd) via separate Turbuhalers. Clinic, diary card and asthma-related health-care resource utilisation data were collected. Improvement in mean morning peak expiratory flow (PEFam was similar in the Salm/FP and Form+Bud groups. Both PEFam and mean evening PEF (PEFpm) increased by a clinically significant amount (>20 L/min) from baseline in both treatment groups. The mean rate of exacerbations (mild, moderate or severe) was significantly lower in the Salm/FP group (0.472) compared with the Form+Bud group (0.735) (ratio = 0.64; P < 0.001), despite the three-fold lower microgram inhaled corticosteroid dose in the Salm/FP group. Patients in the Salm/FP group also experienced significantly fewer nocturnal symptoms, with a higher median percentage of symptom-free nights (P = 0.04), nights with a symptom score <2 (P = 0.03), and nights with no awakenings (P = 0.02). Total asthma-related health-care costs were significantly lower in the Salm/FP group than the Form+Bud group (P<0.05). Both treatments were well tolerated, with a similar low incidence of adverse events. This study showed that in symptomatic patients with moderate-to-severe asthma, Salm/FP (50/250 microg bd), administered in a single convenient device (Diskus), was at least as effective as an approximately three-fold higher microgram corticosteroid dose of Bud (800 microg bd) given concurrently with Form (12 microg bd) in terms of improvement in PEFam, and superior at reducing exacerbations and nights with symptoms or night-time awakenings. Salm/FP was also the less costly treatment due primarily to lower hospitalisation and drug costs.

Reversal of human allergen-specific CRTH2+ T(H)2 cells by IL-12 or the PS-DSP30 oligodeoxynucleotide

BACKGROUND

The chemoattractant receptor homologous molecule expressed on T(H)2 cells (CRTH2) is a receptor for prostaglandin D(2), which among human T cells is selectively expressed by T(H)2 and type 2 cytotoxic effectors.

OBJECTIVE

Our purpose was to assess whether the cytokine production profile of T(H)2 effectors could be reversed by exploiting their selective expression of CRTH2.

METHODS

CRTH2(+) T cells were purified from the blood of allergic subjects, stimulated with the specific allergen in the absence or presence of IL-12, and assessed by flow cytometry at the single-cell level for their ability to produce IL-4 and/or IFN-gamma after antigen or polyclonal stimulation.

RESULTS

Both IL-12 and the PS-DSP30 oligodeoxynucleotide enabled CRTH2(+) allergen-stimulated T(H)2 cells to produce IFN-gamma. This change in the profile of cytokine production by T(H)2 cells from allergic subjects was related to the upregulation of IL-12 receptor beta2 chain and was associated with the loss of CRTH2.

CONCLUSIONS

These data demonstrate that the cytokine production pattern of fully differentiated T(H)2 effectors can be changed to a less polarized profile, thus providing the physiologic basis for new immunotherapeutic strategies in allergic disorders.

Defective production of LIF, M-CSF and Th2-type cytokines by T cells at fetomaternal interface is associated with pregnancy loss

Development of CD4+ helper T (Th) cells into type 1 (Th1) or type 2 (Th2) effectors can be influenced by hormones enhanced during pregnancy. Progesterone, at concentrations comparable to those found at fetomaternal interface, promotes the production of IL-4 and IL-5, whereas relaxin promotes the production of IFN-gamma by T cells. Furthermore, Th1-type cytokines promote allograft rejection and, therefore, may compromise pregnancy, whereas Th2-type cytokines, which inhibit Th1 responses, may allow allograft tolerance. In addition, T cell production of Leukemia Inhibitory Factor (LIF) and macrophage-stimulating factor (M-CSF), which are essential for embryo implantation and development, are up-regulated by IL-4 and progesterone. Finally, a direct cause-and-effect relationship between the defective production of LIF, M-CSF and Th2-type cytokines by T cells present at feto maternal interface and the pregnancy loss has been observed.

Production of IL-4 and leukemia inhibitory factor by T cells of the cumulus oophorus: a favorable microenvironment for pre-implantation embryo development

The nature and the functional activity of immunocytes present in the cumulus oophorus, a mass of cells surrounding the oocyte, were examined here for the first time. The cumuli oophorus were obtained from women who had taken part in an in vitro fertilization program and were suffering from blocked fallopian tubes. Both macrophages and CD4(+) T cells were detected in all cumuli. CD4(+) T cell clones, generated from T cells of these cumuli, showed higher potential to produce IL-4 and leukemia inhibitory factor (LIF) than CD4(+) T cell clones generated from peripheral blood or ovary specimens from the same women. More importantly, IL-4 and LIF, but not IFN-gamma mRNA was found to be constitutively expressed in vivo by cumulus oophorus cells. Progesterone is highly produced by the cumulus oophorus/oocyte complex. We recently showed that progesterone up-regulates the production of LIF by T cells and that the progesterone-induced LIF production is mediated by IL-4. Progesterone produced by cumulus granulosa cells may favor IL-4 production by T cells, which in turn can produce LIF. As the treatment with LIF enhances the in vitro growth and development of mammalian embryos, our data suggest that T cells present in the cumulus oophorus produce cytokines that may provide a microenvironment suitable for pre-implantation development of the mammalian embryo.

Chemoattractant receptors expressed on type 2 T cells and their role in disease

The existence of two functionally distinguished populations among T cells has been established in both mice and humans. Type 1 T helper (Th1) cells are involved in the defense against intracellular bacteria and many viruses, while type 2 Th cells (Th2) are the major actors in the response against parasites and play a central role in allergic inflammation. More recently, several data have suggested that some chemokine receptors are tightly regulated on T cells, and in accordance with this selective expression, Th1 and Th2 cells can be differentially recruited by specific chemokines to the inflammatory sites. Among Th2-associated chemokine receptors, CCR3, CCR4 and CCR8 have been described to play a central role in allergic inflammation. However, CCR3 is mainly expressed on basophils, eosinophils and mast cells, but it is poorly expressed by Th2 cells, and CCR4 is also expressed by Th subsets different from Th2 cells. So far, the chemoattractant receptors which among T cells appear to be selectively expressed by Th2 cells or their subsets are CCR8 and CRTH2. The ligand for CRTH2 is not a chemokine, but is prostaglandin (PG)D2, which is able to attract basophils, eosinophils, Th2 cells and type 2 cytotoxic (Tc2) CD8+ T lymphocytes. The selective expression of CRTH2 on Th2 and Tc2 cells may be useful to develop new therapeutic strategies against allergic diseases and against other immune disorders. Additional studies, however, are required to understand its effective importance in the induction and maintenance of Th2- or Tc2-mediated response and inflammation.

Production of IL-4 and leukemia inhibitory factor by T cells of the cumulus oophorus: a favorable microenvironment for pre-implantation embryo development

The nature and the functional activity of immunocytes present in the cumulus oophorus, a mass of cells surrounding the oocyte, were examined here for the first time. The cumuli oophorus were obtained from women who had taken part in an in vitro fertilization program and were suffering from blocked fallopian tubes. Both macrophages and CD4(+) T cells were detected in all cumuli. CD4(+) T cell clones, generated from T cells of these cumuli, showed higher potential to produce IL-4 and leukemia inhibitory factor (LIF) than CD4(+) T cell clones generated from peripheral blood or ovary specimens from the same women. More importantly, IL-4 and LIF, but not IFN-gamma mRNA was found to be constitutively expressed in vivo by cumulus oophorus cells. Progesterone is highly produced by the cumulus oophorus/oocyte complex. We recently showed that progesterone up-regulates the production of LIF by T cells and that the progesterone-induced LIF production is mediated by IL-4. Progesterone produced by cumulus granulosa cells may favor IL-4 production by T cells, which in turn can produce LIF. As the treatment with LIF enhances the in vitro growth and development of mammalian embryos, our data suggest that T cells present in the cumulus oophorus produce cytokines that may provide a microenvironment suitable for pre-implantation development of the mammalian embryo.

Microchimerism and systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disease characterized by progressive fibrosis of the skin and internal organs. SSc is an immunologically mediated disease. A prominent immunological abnormality in SSc patients is the presence of circulating autoantibodies against a variety of nuclear proteins. Furthermore, SSc is characterized by the presence of increased numbers of activated T cells, with the prevalence of CD4+ cells, present in the periphery of skin lesions as well as in other organs in the early stages of the disease. We have recently shown the existence of a predominant activation of IL-4-producing Th2-like T cells in patients with SSc, which may account for the major alterations which occur in this disease. SSc has clinical and serological similarities to chronic graft versus host disease (cGVHD), although there are some important differences. T cells, which orchestrate the tissue damage, are present in great amounts in the inflammatory infiltrates in SSc- and cGVHD-affected tissues. More importantly, T cells from cGVHD tissues produce Th2-like cytokines, thus showing a pathogenetic similarity with SSc. SSc has been postulated as a type of cGVHD resulting from the transplacental transfer of cells between mother and fetus. Very recently, we have shown that in SSc, the microchimeric T cells react with the maternal MHC antigens and are able to produce Th2-type cytokines. Both features are characteristics of cGVHD, supporting the hypothesis that SSc is a disease similar to cGVHD.

Th1 and th2 responses, HIV-1 coreceptors, and HIV-1 infection

The Th1/Th2 model provides an interesting paradigm for understanding several pathophysiological processes and possibly for developing new immunotherapeutical strategies. In HIV-1 infection the interaction between the type of HIV-1 strain and the pathway of the ongoing T-cell effector response, despite its complexity, may represent one of the crucial mechanisms in determining the outcome of virus infection. While the possibility of an HIV-1-driven Th1 to Th2 switch of the immune response is still debated, evidence is accumulating to suggest that cytokines produced during an immune response can contribute to promote a selective pressure toward the evolution of HIV-1 viral strains with different tropism. This article summarizes the results of our recent studies in which the expression of CCR5 and CXCR4 HIV-1 co-receptors, as well as the activity of R5- or X4- tropic strains of HIV-1 in different in vitro models of Th1/Th2 polarization was analyzed.

Oligoclonal T cell repertoire in cerebrospinal fluid of patients with inflammatory diseases of the nervous system

OBJECTIVE

To evaluate the T cell receptor beta chain variable region (TCRBV) gene usage ex vivo in CSF cells and peripheral blood mononuclear cells (PBMCs) collected from patients with autoimmune and inflammatory diseases of the nervous system.

METHODS

A novel sensitive seminestedpolymerase chain reaction coupled with heteroduplex analysis was developed.

RESULTS

Under these experimental conditions, the minimal number of cells required for the analysis of the whole T cell repertoire was established at 2.5x10(4)-sufficient to evaluate most of the samples collected during diagnostic lumbar punctures. In the 21 patients examined, restrictions in TCRBV gene family usage were not seen. However, using heteroduplex analysis, oligoclonal T cell expansions were found in the CSF of 13 patients and monoclonal expansions in five patients. The T cell abnormalities found did not correlate with intrathecal IgG production or with any clinical variable considered.

CONCLUSION

T cell clonal expansions, useful for further characterisation of pathogenetic T cells, can be found during the course of nervous system inflammations, but this abnormality is probably not disease specific.

Faecal carriage of Verocytotoxin-producing Escherichia coli O157 and carcass contamination in cattle at slaughter in northern Italy

A study on the prevalence of the faecal carriage of Verocytotoxin (VT)-producing Escherichia coli (VTEC) O157 and on the rate of carcass contamination was carried out on feedlot cattle and dairy cows at slaughter in northern Italy. Between April 1998 and January 1999, 12 sampling visits were performed on different days in seven different slaughterhouses. At each visit, 5-12 animals consecutively slaughtered were selected. From each animal, faeces were collected from the rectum immediately after slaughter and surface swabs were taken from the leg region and the diaphragmatic insertion of the carcass. All samples were examined for the presence of VTEC O157 using an immunomagnetic separation technique. A total of 100 animals coming from 60 different farms were examined. In total, VTEC O157 was isolated from the intestinal content of 17, and from the carcasses of 12 of the 100 animals examined. In particular, VTEC O157 was recovered from six (35.3%) out of the 17 carcasses from which the organism had previously been isolated from rectal content and from six (7.3%) of the 82 carcasses of the stool-negative cattle. In seven carcasses, VTEC O157 was isolated from the leg area, in two carcasses from the diaphragmatic area, and in three carcasses from both areas. Major differences in the prevalence of VTEC O157 were observed in the different groups of cattle sampled. In 7 of the 12 sampling visits, all the specimens examined were negative, while 16 of the 17 positive stool samples and 11 of the 12 positive carcass swabs were collected during three of the visits, performed in June in three different abattoirs. In these three visits, the ratios between the percentage of animals carrying VTEC O157 in the stools and the percentage of contaminated carcasses were 0.33, 0.57, and 1.66, respectively; thus, confirming that slaughter practices can largely influence the rate of carcass contamination. Phage typing and PFGE analysis of VTEC O157 isolated from samples collected at the same visit suggested that both auto- and cross-contamination occurred.

Environmental factors favoring the allergen-specific Th2 response in allergic subjects

Allergen-reactive type 2 helper T cells (Th2) play a triggering role in the activation and/or recruitment of IgE antibody-producing B cells, mast cells, and eosinophils, i.e., the cellular triad involved in the allergic inflammation. Interleukin (IL)-4 production at the time of antigen presentation to the Th cell is critical for the development of Th2 cells. Other cytokines, such as IL-1 and IL-10, and hormones, such as calcitriol and progesterone, also play a positive role. In contrast, cytokines such as interferon (IFN)-alpha, IFN-gamma, IL-12, and transforming growth factor (TGF)-beta, and relaxin play a negative regulatory role on the development of Th2 cells. However, the mechanisms underlying the preferential activation by environmental allergens of Th2 cells in atopic individuals still remain obscure. Some gene products selectively expressed in Th2 cells or selectively controlling the expression of IL-4 have recently been described. Moreover, cytokines and other gene products that dampen the production of IL-4, as well as the development and/or the function of Th2 cells, have been identified. These findings allow us to suggest that the upregulation of genes controlling IL-4 expression and/or abnormalities of regulatory mechanisms of Th2 development and/or function may be responsible for Th2 responses against common environmental allergens in atopic subjects.

Interferon-inducible protein 10, monokine induced by interferon gamma, and interferon-inducible T-cell alpha chemoattractant are produced by thymic epithelial cells and attract T-cell receptor (TCR) alphabeta+ CD8+ single-positive T cells, TCRgammadelta+ T cells, and natural killer-type cells in human thymus

Strong reactivity for interferon-inducible protein 10 (IP-10), monokine induced by interferon gamma (Mig), and interferon-inducible T-cell alpha chemoattractant (I-TAC) was found in epithelial cells mainly localized to the medulla of postnatal human thymus. The CXC chemokine receptor common to the 3 chemokines (CXCR3) was also preferentially expressed in medullary areas of the same thymuses and appeared to be a property of 4 distinct populations: CD3+ T-cell receptor (TCR) alphabeta+ CD8+ single-positive (SP) T cells, TCRgammadelta+ T cells, natural killer (NK)-type cells, and a small subset of CD3+(low) CD4+ CD8+ TCRalphabeta+ double-positive (DP) T cells. IP-10, Mig, and I-TAC showed chemoattractant activity for TCRalphabeta+ CD8+ SP T cells, TCRgammadelta+ T cells, and NK-type cells, suggesting their role in the migration of different subsets of mature thymocytes during human thymus lymphopoiesis.

Cell cycle-dependent expression of CXC chemokine receptor 3 by endothelial cells mediates angiostatic activity

Endothelial cell receptors for the angiostatic chemokines IFN-gamma-inducible protein of 10 kDa (IP-10) and monokine induced by IFN-gamma (Mig) have not yet been identified, and the mechanisms responsible for the effects of these chemokines on angiogenesis are still unclear. IP-10 and Mig share a common functional receptor on activated T lymphocytes, named CXC chemokine receptor 3 (CXCR3). Using in situ hybridization and immunohistochemistry, we show that CXCR3 is expressed by a small percentage of microvascular endothelial cells in several human normal and pathological tissues. Primary cultures of human microvascular endothelial cells (HMVECs) likewise express CXCR3, although this expression is limited to the S/G2-M phase of their cell cycle. Both IP-10 and Mig, as well as the IFN-gamma-inducible T-cell alpha chemoattractant (I-TAC), which all share high-affinity binding for CXCR3, block HMVEC proliferation in vitro, an effect that can be inhibited by an anti-CXCR3 antibody. These data provide definitive evidence of CXCR3 expression by HMVEC and open new avenues for therapeutic interventions in all conditions in which an angiostatic effect may be beneficial.

Role of hormone-controlled Th1- and Th2-type cytokines in successful pregnancy

Development of CD4+ helper T (Th) cells into type 1 (Th1) or type 2 (Th2) effectors, as characterized by their opposite pattern of cytokine production, can be influenced by several factors, including hormones. Progesterone promotes the production of IL-4 and IL-5, whereas relaxin promotes the production of IFN-gamma by T cells. Leukemia inhibitory factor (LIF), essential for embryo implantation, is up-regulated by IL-4 and progesterone. Moreover, the production of LIF and/or Th2 cytokines by decidual T cells contributes to the maintenance of pregnancy. Our results suggest that relaxin and progesterone may contribute to the regulation of the immune homeostasis during pregnancy.

Th1/Th2 cells, their associated molecules and role in pathophysiology

Cytokines, chemokines, and/or chemokine receptors associated with type 1 T helper (Th1) or Th2 cells play a role in different physiological conditions, such as T lymphopoiesis and pregnancy, as well as in pathological conditions, such as unexplained recurrent abortions, proliferative glomerulonephritis, and control of angiogenesis.