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Ehab Azab,1 Alaa Attia,1,2 Wael Yaghmoor,1 Salwa Aldahlawi,1 Abdel-Rahman Youssef1,3 1Department of Basic and Clinical Oral Sciences, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia; 2Department of Oral Medicine and Periodontology, Faculty of Dentistry, Al-Azhar University, Assiut, Egypt; 3Department of Microbiology and Immunology, Faculty of Medicine, Suez Canal University, Ismailia, EgyptCorrespondence: Ehab Azab, Department of Basic and Clinical Oral Sciences, Faculty of Dentistry, Umm Al-Qura University, Prince Sultan Road, Makkah, 21421, Saudi Arabia, Tel +966 12 527 0000, Email etazab@uqu.edu.saPurpose: This study aimed to evaluate and compare Dickkopf-related protein-1 (DKK1) serum levels and periodontal clinical parameters of smokers and nonsmokers with periodontitis at baseline and after nonsurgical periodontal treatment.Patients and Methods: A prospective comparative study was conducted among 24 patients with periodontitis who were divided according to the smoking habits into two groups: nonsmokers (G1) and smokers (G2). All the participants were assessed clinically by recording the probing depth (PD), clinical attachment loss (CAL), plaque index (PI), and bleeding index (BI), and immunologically by measuring the DKK1 serum levels at baseline and six weeks after nonsurgical periodontal therapy.Results: The two groups showed a significant decrease in PI, BI, and CAL after periodontal therapy (p < 0.05), while PD was significantly reduced in G1 (p = 0.005). The PI mean value was significantly higher at the baseline in G2 versus G1 (p = 0.050), while PD, BI, and CAL values were not significantly different between the groups (p = 0.056, p = 0.241, and p = 0.381, respectively). For DKK1 serum levels, there was a statistically significant decrease after treatment compared to the baseline for both groups (G1: p < 0.001; G2: p < 0.001) but no significant difference before (p = 0.131) and six weeks after treatment (p = 0.334) between the two groups.Conclusion: Although nonsurgical periodontal treatment effectively improved periodontal clinical parameters and reduced DKK1 serum levels, there were no significant differences in the DKK1 serum levels among the smokers and nonsmokers with periodontitis.Keywords: periodontitis, dickkopf-related protein-1, periodontal therapy, Wnt signaling, bone cells

Smokeless tobacco (SLT) has been reported to have deleterious effects on the health of its users. This study aims to analyze the constituents of locally collected SLT sample extracts (S1–S11) from Tabuk region of Saudi Arabia using GC-MS and investigate their cytotoxic effect on human gingival fibroblasts (hGFs), normal human fibroblasts (MRC5), and two cancer cell lines (HT29 and HepG2) using MTT assay. GC-MS results showed that pyridine, 3-(1-methyl-1H-pyrrol-2-yl)-, tetracyclo[4.4.1.1(7,10).0(2,5)]dodec-3-en-11-ol, and cotinine were found in S1, while ethyl iso-allocholate was traced in S2. Compounds 9,12-octadecadienoic acid, ethyl ester, 7-methyl-Z-tetradecen-1-ol acetate, cis-10-heptadecenoic acid and octadecanoic acid, ethyl ester, and nicotine traces were found in S4, while compound 3,7,11,15-tetramethyl-2-hexadecen-1-ol, tetradecamethyl-hexasiloxane, and phytol in S5. Additionally, octadecamethyl cyclononasiloxane, oleic acid, and trimethylsilyl ester were found in S6 and S9, respectively. Interestingly, extracts S4, S10, and S6 were the most cytotoxic to the normal fibroblasts (hGF and MRC5, with low selectivity index

Background: Biocompatibility is an essential property for any dental root repair material that may interact with the surrounding periodontal tissues. We hypothesise that the three mineral trioxide aggregate (MTA) restorative brands ProRoot MTA, MTA Flow and Harvard MTA have similar biocompatibility. To test this hypothesis, we compared the cytotoxic effects of these materials on human gingival fibroblast (GF). Methods: MTA cements were prepared, and after completion of setting, they were incubated in Dulbecco's Modified Eagle Medium for 1 day or 4 days to obtain low and high concentrations of MTA elutes respectively. The elutes of MTA supplemented with fetal bovine serum were added to GF and incubated for 3 days at 37 °C and 5% CO2. Untreated cells were used as control. The cell viability was assessed using a 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay at 24, 48 and 72 h. Results: After 24 h, the MTT assay showed that both 1- and 4-day elutes of MTA flow and Harvard MTA reduced cell viability significantly compared to control (P

To investigate the in vitro cytotoxic effects of Bis-GMA-containing and Bis-GMA-free flowable resin-based composites (RBCs) on primary human gingival fibroblast cells (hGFc) using direct and indirect curing methods and three different light-curing units (LCUs).Cells were isolated and cultured in vitro in 24-well plates. The plates were divided into treatment (cells with RBC), control (cells only), and blank (media only) groups. In the treatment groups, two types of nanohybrid flowable RBCs were used: Bis-GMA-free and Bis-GMA groups. Each treatment group was subdivided according to the curing method, i.e., direct curing (RBC was injected into the wells and cured directly on the attached cells) and indirect curing (the samples were pre-cured outside of the well plate and then added to the well plate with cells). To vary the LCU, the subgroups were further divided into three groups: multiple-emission peak light-emitting diode, single-emission peak light-emitting diode, and quartz-tungsten-halogen units. Curing was conducted for 20 seconds. The hGFc cytotoxicity was evaluated via 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay after 24, 48, and 72 hours of culturing.The MTT assay results showed that both RBCs were significantly cytotoxic toward hGFc compared to the control group (p0.0001). The Bis-GMA group was significantly more cytotoxic to the cells compared to the Bis-GMA-free group. In addition, the curing method and time interval affected cell viability regardless of the LCU used.The Bis-GMA flowable RBC and direct curing method had the highest cytotoxic effects on hGFc regardless of the LCU used. Careful selection of flowable RBCs and proper curing techniques are required to decrease the cytotoxic effects on hGFc and improve the clinical handling of oral tissues.

Objective Allogeneic and xenogeneic acellular dermal matrix (ADM) grafts have been used to treat periodontal soft tissue defects. The purpose of the current study was to compare the effect of human ADM (AlloDerm) and porcine ADM (Derma) on human primary gingival fibroblasts in vitro regarding the biocompatibility test.Materials and Methods Gingival fibroblasts were obtained from healthy adult gingiva and seeded on AlloDerm or Derma ADM in 96-well plate. The control cells were grown on a surface-treated polystyrene cell-culture plate without matrix. The cells were cultured for 3, 7, and 14 days. The fibroblasts morphology was examined using inverted microscopy, and the cell viability of fibroblasts adherent to the dermal matrix was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay after 3, 7, and 14 days in culture. The data were statistically evaluated by one-way analysis of variance. p-Value of 0.05 was considered significant.Results Gingival fibroblasts adjacent to the AlloDerm and Derma matrices were healthy, attached to the well, and did not exhibit any cytopathic changes similar to control. There were no statistically significant differences in the cell viability between the gingival fibroblasts attached to Derma and AlloDerm on day 3 (p = 0.841), day 7 (p = 0.198), and day 14 (p = 0.788).Conclusion Considering this in vitro study’s limitations, both human and porcine ADM were compatible with the surrounding human primary gingival fibroblasts. No significant differences were observed in the cell viability between the gingival fibroblasts that were attached to Derma and AlloDerm.

Background: Neutrophils are an essential part of innate immunity and play a crucial role in controlling infection caused by Neisseria meningitidis. The Moraxella catarrhalis ubiquitous surface protein A1 (UspA1)-based recombinant polypeptide binds to the carcinoembryonic antigen-related cellular adhesion molecule (CEACAM) 1 receptor on host cells and blocks binding of the mucosal pathogens to human epithelial cells and T cells. Aim of the study: Since the CEACAM1 receptor is expressed on neutrophils, the aim of this study was to investigate the effect of CEACAM1-binding recombinant polypeptide on the ability of neutrophils to kill Neisseria meningitidis. Methods: The effect of CEACAM1-binding recombinant polypeptide on the phagocytic killing of Neisseria meningitidis by neutrophils was assessed by incubation of neutrophils with CEACAM1-binding recombinant polypeptide (UspA1 527–665) or with CEACAM1-non-binding polypeptide control (UspA1 659–863) for one hour before infection with Neisseria meningitidis. The surviving bacteria were released and counted. Results: 30 minutes after infection of neutrophils with Neisseria meningitidis, the survival of bacteria in presence of CEACAM1-binding recombinant polypeptide was 64% compared to 52% with control peptide and 43% without peptide. However, one-hour after infection, the surviving bacteria was 32% in presence of CEACAM1-binding recombinant polypeptide compared to 18% with control peptide and 22% without peptides. Conclusion: Although CEACAM1-binding polypeptide reduced the killing of Neisseria meningitidis by neutrophils, it did not entirely stop phagocytosis and killing of bacteria.

Background: Infectious diseases are the major causes of morbidity and mortality related to clinical, diagnostic and therapeutic procedures. Dentists should apply the guidelines for infection control during practice to prevent cross infection. This study aimed to assess the effect of medical education on the knowledge, attitudes and compliance among dental students regarding infection control measures at the dental teaching hospital faculty, Umm Al-Qura University (UQU), Makkah, Saudi Arabia. Methods: A cross-sectional comparative study was performed to assess the knowledge, attitude and compliance towards infection control using a structured questionnaire. All students attending dental clinics in the 4th, 5th and 6th grades (n = 186), 94 males and 92 females participated in this study. Results: Most dental undergraduate students have a knowledge of infection control in dental clinics including sterilization (83%), personal protective equipment (87.1%), proper hand hygiene (86.3%), vaccination (97.9%) and safe disposal of clinical waste (83.9%). More than 90% of UQU dental students were tested for Hepatitis B virus (HBV), performed wrap and disinfection of the dental unit before treating patients and wore personal protective equipment (PPE). The 6th grade dental students have superior knowledge compared to 4th and 5th grade dental students. The attitude and compliance to infection control guidelines within each grade were comparable. However, a between grade comparison showed that the 4th grade students had a better attitude and compliance.

Objective The main purpose of this article was to evaluate the effect of probiotics used as an adjunctive to scaling and root planing (SRP) on the periodontal parameters and matrix metalloproteinase-8 (MMP-8) levels in gingival crevicular fluid (GCF) of chronic periodontitis patients. Materials and Methods A total of 25 chronic periodontitis patients who completed the treatment course of 40 subjects, aged 25 to 58 years, participated in this study. They were categorized into two groups: the first group was treated by SRP while the second group was treated by SRP and probiotic lozenges twice a day for 30 days. All patients were evaluated clinically by measuring the plaque index, bleeding index (BI), pocket depth, clinical attachment loss, and immunologically by assaying GCF/MMP-8 at baseline and 30 days after periodontal management. Results There was a significant improvement in periodontal parameters after SRP treatment with and without probiotic lozenges in both groups. However, there was a significant decrease in the BI (p = 0.05) in SRP and probiotic lozenges group after 30 days compared with SRP alone. In addition, there was a significant decrease in GCF/MMP-8 levels after 30 days in patients managed by SRP only (p = 0.017) compared with the baseline in both groups, whereas a highly significant decrease in patients treated by SRP and probiotics (p = 0.001). Conclusion The current study suggested that the probiotics might have a beneficial effect on clinical and immunological outcomes in the management of chronic periodontitis patients. Further research is needed on a large-scale population and for a long recall time to confirm the response to probiotics as an adjunctive to SRP.

Introduction: The main aim of root canal therapy is adequate sealing to prevent reinfection with subsequent periapical disease. The aim: The aim of this study was to compare the sealing ability of root canal filled teeth using three different sealers and three different restorative materials by bacterial penetration method during a 30-day period. Materials and Methods: Seventy-two single rooted teeth were prepared using Protaper Next. Obturation was done using single cone technique .The teeth were randomly divided into three groups of 24 samples according to the sealer used as following; group 1: Bioceramic sealer (BS), group 2: MTA fillapex (MTA) and group 3: Tagdseal sealer (TG). The samples then randomly subdivided into 3 groups of 8 samples according to the coronal restoration of the specimens as following; subgroup A: Composite (Tetric Ceram + Tetric N Bond), subgroup B: Compomer (Compoglass F + Adhese SE) and subgroup C:Glass Ionomer (Ketac N + Ketac primer).Therefore, there was 9 final groups; I, II, III, IV, V, VI, VII, VIII, IX.After setting time, the samples were incorporated in a bacterial leakage model, using E. faecalis. Leakage was evaluated by turbidity in lower chamber in 30-day period. Statistical analysis was done using One-wayANOVA test, and post hoc pairwise comparison was done using Tukey test. Results: The results showed that group I (BS - Composite) presented the lowest means of bacterial leakage after all periods of evaluation. On the other hand, the (MTA – Glass Ionomer) material showed the highest means of leakage. There was a significant difference between the means of the bacterial colonies recorded in the nine groups at one, 2 and 4 weeks; while at 3 weeks the difference was insignificant. Conclusion : Bioceramic sealer with composite restoration showed the least bacterial leakage.

It is well established that the PKHD1 mutations are associated with autosomal recessive polycystic kidney disease (ARPKD). Although, PKHD1 mutations are also detected in certain cancer types, to our knowledge in rare tumors such as, atypical teratoid rhabdoid tumor (ATRT), primary neuro-ectodermal tumor (PNET), atypicalchoroid plexus papilloma (a-CPP), amelanotic ano-rectal melanoma (AMM), and breast phyllodes tumors PKHD1 mutations profiling is not reported.In order to determine the PKHD1 gene mutation patterns in the brain, rectal, and breast tumors we have analyzed these tumor DNA by Ion Proton Next generation DNA sequencing.Next-generation DNA sequencing on Ion Proton identified unique and common missense mutations in the brain, breast and ano-rectal tumors. All mutations were benign, and only one pathogenic mutation in p. (Cys3346Arg) found in AMM tumor. In phyllodes tumor of breast, two unique missense variants were detected (rs113562492) p. (Met2841Val); and (rs137972270) in p. (Arg589Cys) and these variants are not present in other tumors tested. The variant rs137972270 was reported only in two cases sofar in ClinVar database. Missense variants such as rs115045643, rs116809571, rs115338476, and rs76895755 are found only in PNET, and a variant rs62406032 in a-CPP, another one rs35445653 in ATRT cases were unique for these tumors, which are not present in other tumors. Several synonymous and intronic variants of PKHD1 gene were also found in these tumors. A synonymous variant p. (Asp395Asp), rs1896976 and two intronic SNPs viz., rs1326605, and rs1571084 were found in all tumors tested. The SNP rs9395699 in IVS66 was found uniquely in IPC breast tumor only in this study. Allele coverage, allele ratio, p-value, Phred qual score, sequencing coverage, alleles frequencies were also analysed, the p-values and Phred quality score were significantly higher.These tumors did not have any insertion/ deletion mutations, nonsense, or truncated mutations in it. The screening of PKHD1 gene revealed signature mutations for the solid tumors studied by NGS method. This investigation may help in understanding these tumor pathology at molecular level.

Hepatitis-B Virus (HBV) infection is a serious health problem that can be prevented by vaccination. Dental Health Care Workers (DHCWs) are at-risk of occupational exposure to HBV infection. This study was aimed to assess the prevalence of HBV and evaluate the immune response to hepatitis B vaccine among DHCWs in Dental Teaching Hospital, Umm Al-Qura University, Saudi Arabia. A cross-sectional study was conducted on 139 DHCWs, 71 males and 68 females. Blood samples were collected and the levels of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) were measured by Chemiluminescent Microparticle Immunoassay. The prevalence of HBV among DHCWs was zero (0.0%). The hepatitis B vaccine was given to 95% of DHCWs. Among the vaccinated participants, 90.1% (n=119) have protective immunity to hepatitis B. An inverse correlation between anti-HBs levels and increasing the duration of vaccination (P0.0001) was found. We compared the anti-HBs levels in 28 students who received childhood vaccine and revaccinated at age of 21. The anti-HBs concentration was greater than 10mIU/mL (protected) in 17.9% of those who had childhood vaccine compared to 100% one-year after revaccination. The mean of anti-HBs levels for childhood vaccine was 5.6 mIU/mL and these levels increased significantly to 620 mIU/mL after recent revaccination (P0.0001). In conclusion, Hepatitis B vaccine is effective in prevention of HBV infection among DHCWs. Non-protected individuals should be identified and revaccinated.

Leptin is pro-inflammatory mediator associated with the pathogenesis of periodontitis. The objective of the current study was to assess the levels of leptin in serum and gingival crevicular fluid (GCF) in chronic periodontitis (CP) patients. This cross-sectional study was conducted in Dental Teaching Hospital, Umm Al-Qura University, Makkah, Saudi Arabia. Forty-five individuals participated in this study: 25 with chronic periodontitis patients and 20 periodontally healthy controls. The patients were selected based on the criteria of American Academy of Periodontology using probing depths, bleeding on probing, clinical attachment loss and radiographs. GCF and serum samples were collected to estimate the leptin concentrations using enzyme-linked immunosorbent assay kits. Serum leptin levels were markedly higher in chronic periodontitis patients than in the healthy group (P < 0.00001). Although GCF leptin levels of chronic periodontitis patients were higher than the healthy group but this difference was not statistically significant (P Value = 0.5198). In conclusion, these results indicate positive association between serum leptin concentrations and chronic periodontitis. However, there was no significant correlation between GCF leptin level and periodontitis. Further studies are required to confirm these finding.

Purpose: The anion channel protein band 3 is the main target of the pathogenic red blood cells (RBC) autoantibodies in New Zealand black (NZB) mice. CD4 T cells from NZB mice with autoimmune hemolytic anemia respond to band 3. Previously, we have shown that IL-10 and peptides containing a dominant T cell epitope from red cell band 3 modulate autoimmune hemolytic anemia in NZB mice. Because of the immunoregulatory role of IL-10 in autoimmune diseases, we aim to identify individual band 3 peptides that induce high IL-10 production and simultaneously suppress CD4 T cell proliferation and to investigate the effect intranasal administration of IL-10 producing band 3 peptides on autoantibody responses of NZB mice. Methods: Splenic CD4 T cells of NZB mice were isolated and stimulated by co-culture of T cells with individual band 3 peptides. IL-10 production was measured by enzyme-linked immunosorbent assay and proliferative response of CD4 T cells was estimated by incorporation of [3H] thymidine assay. NZB mice were given either PBS, or peptides 25 (241–251) and 29 (282–296) or both peptides intranasally on three occasions at 2-day intervals. The mice were bled at 6, 10 and 18 weeks after peptide inhalation, and the number of RBC auto-antibodies was measured by DELAT and hematocrit values were assessed. Results: Peptides 25 (241–251) and 29 (282–296) induced the highest IL-10 production by CD4 T cells. These peptides also inhibited the peak T cell proliferative response. 6 and 10 weeks after peptide inhalation, the total IgG, IgG1 and IgG2a in mice treated with both peptides 241–251 and 282–296 were significantly higher than control (P

T cells may interact with a number of bacterial surface antigens, an encounter which has the potential to downmodulate host immune responses. Neisseria meningitidis , a human colonizer and an agent of septicemia and meningitis, expresses Opa proteins which interact with the CEACAM1 receptor expressed on activated T cells. Since CEACAM1 can act as an inhibitory receptor and T cells in subepithelial tissues may encounter whole bacteria, which often express Opa proteins in vivo, this study assessed primarily if Opa proteins expressed on meningococci affect T-cell functions. In addition, Opa-containing outer membrane vesicles (OMV) have been used as vaccine antigens, and therefore Opa + and Opa − OMV were also studied. While Opa + bacteria adhered to CEACAM-expressing T cells, both the Opa + and Opa − phenotypes induced no to a small transient depression, followed by a prolonged increase in proliferation as well as cytokine production. Such responses were also observed with heat-killed bacteria or OMV. In addition, while anti-CEACAM antibodies alone inhibited proliferation, on coincubation of T cells with bacteria and the antibodies, bacterial effects predominated and were Opa independent. Thus, while Opa proteins of N. meningitidis can bind to T-cell-expressed CEACAM1, this is not sufficient to overcome the T-cell recognition of bacterial factors, which results in a proliferative and cytokine response, an observation consistent with the ability of the host to establish lasting immunity to Opa-expressing meningococci that it frequently encounters. The data also imply that Opa-proficient vaccine preparations may not necessarily inhibit T-cell functions via CEACAM1 binding.

The factors that influence the relative contribution of the T cell subsets to allograft rejection remain unclear. We compared skin and heart rejection in CD4 Knockout (KO), and CD8 KO mice across full-, minor-, and class II histocompatibility antigen (HA) mismatches. Skin allografts were rejected by either CD4+ or CD8+ T cells alone at any degree of antigenic mismatch. However, either the absence of CD4+ cells or a lesser degree of HA mismatch resulted in prolongation of graft survival. In contrast, fully allogeneic heart grafts were accepted in CD4 KO recipients, and minor HA mismatched heart grafts were accepted by both CD4 KO and CD8 KO mice. Thus, the T cell subsets required for allograft rejection are determined by the immunogenicity of the tissue transplanted. In the absence of CD8+ T cells, perforin and Fas ligand (FasL) but not granzyme B mRNA were detected in rejecting grafts. Thus, granzyme B is a CD8+ cytotoxic T lymphocyte (CTL)-specific effector molecule.

T cells may interact with a number of bacterial surface antigens, an encounter which has the potential to downmodulate host immune responses. Neisseria meningitidis, a human colonizer and an agent of septicemia and meningitis, expresses Opa proteins which interact with the CEACAM1 receptor expressed on activated T cells. Since CEACAM1 can act as an inhibitory receptor and T cells in subepithelial tissues may encounter whole bacteria, which often express Opa proteins in vivo, this study assessed primarily if Opa proteins expressed on meningococci affect T-cell functions. In addition, Opa-containing outer membrane vesicles (OMV) have been used as vaccine antigens, and therefore Opa+ and Opa− OMV were also studied. While Opa+ bacteria adhered to CEACAM-expressing T cells, both the Opa+ and Opa− phenotypes induced no to a small transient depression, followed by a prolonged increase in proliferation as well as cytokine production. Such responses were also observed with heat-killed bacteria or OMV. In addition, while anti-CEACAM antibodies alone inhibited proliferation, on coincubation of T cells with bacteria and the antibodies, bacterial effects predominated and were Opa independent. Thus, while Opa proteins of N. meningitidis can bind to T-cell-expressed CEACAM1, this is not sufficient to overcome the T-cell recognition of bacterial factors, which results in a proliferative and cytokine response, an observation consistent with the ability of the host to establish lasting immunity to Opa-expressing meningococci that it frequently encounters. The data also imply that Opa-proficient vaccine preparations may not necessarily inhibit T-cell functions via CEACAM1 binding.

SummaryNew Zealand Black (NZB) mice spontaneously develop autoimmune haemolytic anaemia (AIHA). Here the effect of injecting NZB mice with plasmids encoding IL-4 (pIL-4) or IL-10 (pIL-10) on NZB disease was tested. Both constructs delayed the development of anaemia as judged by increased haematocrit values as compared with controls, but neither altered the IgG1 to IgG2 red blood cell (RBC) bound autoantibody levels. The increased haematocrit value was associated temporally with increased RBC bound IgG in NZB mice treated with pIL-10, but not pIL-4. By contrast, up-regulation of splenic macrophage FcγRIIb2 mRNA was associated temporally with increased haematocrit values in NZB mice given pIL-4. However, no such increase occurred in NZB mice that inhaled a peptide containing a dominant T-cell epitope, although this treatment is known to bias the autoimmune response towards Th2 and to reduce the severity of anaemia. It is considered that IL-4 treatment, in part, ameliorates NZB anaemia by increasing the expression of the inhibitory FcγRIIb2 and thereby reducing the capacity of splenic macrophages to phagocytose autoantibody coated RBC, but that this mechanism does not explain the beneficial effects of the inhaled peptide.

The major target of the pathogenic red blood cell (RBC) autoantibodies in New Zealand black (NZB) mice is the anion channel protein band 3, and CD4+ T cells from NZB mice respond to band 3. Here, we demonstrate that a band 3 peptide 861-875, which is the predominant sequence recognized by NZB T cells in vitro, bears a dominant helper epitope able to modulate the autoimmune hemolyic anemia in vivo. The development of RBC-bound autoantibodies and anemia was accelerated in NZB mice injected with peptide 861-874, which is relatively insoluble, and inhalation of the peptide primed T cells for both peptide 861-874 and band 3 responses. By contrast, inhalation of a soluble analog (Glu861, Lys875) of peptide 861-874 deviated the autoimmune response toward a T helper-2 (Th2) profile, with marked increases in the ratio of interleukin-4 to interferon-γ produced by splenic T cells responding in vitro to either peptide 861-874 or band 3. Moreover, in mice that had received such treatment, the proportion of RBC-bound immunoglobulin G (IgG) molecules that were of the Th2-associated IgG1 isotype was also increased, and anemia was less severe. It is concluded that NZB autoimmune hemolytic anemia is helper dependent and that nasal administration of different peptides containing the dominant T-cell epitope can have potentially detrimental or beneficial effects on the disease. (Blood. 2003; 102:3800-3806)

Cytotoxic T lymphocytes (CTLs) and macrophage-mediated delayed-type hypersensitivity (DTH) responses may both mediate allograft rejection. Furthermore, although allograft rejection is classically considered a type [22, 23, 38, 50, 52] 1 cellular immune response, type-2 cytokines can support rejection. This study examines whether the immunogenicity of the transplanted tissue, as determined by type of tissue (skin versus heart) and degree of antigenic mismatch, influences recruitment of these effector mechanisms. Graft survival, histological appearance and intragraft gene expression (IL-2, IFN-gamma, IL-12 p40, IL-4, IL-10, perforin, Fas ligand (Fas L), iNOS and TNF-alpha) were compared for fully allogeneic, minor histocompatibility (mHC) antigen-mismatched and syngeneic skin and heart grafts. We found mRNA characteristic of CTLs and DTH responses in fully allogeneic and mHC antigen-mismatched skin and heart grafts. Concomitant type-1 and type-2 cytokine gene transcription was seen. These findings demonstrate that the tissue grafted and degree of antigenic disparity between donor and recipient do not restrict the repertoire of cellular immune responses involved in graft rejection. This finding has implications in the design of new immunosuppressive strategies for clinical transplantation.