mit wednesday, may 16, 11 am room e-220, engineering

Highthroughput,highcontentneurobiologicalimagingPeterSo,MITWednesday,May16,11amRoomE-220,EngineeringBuilding2

Asanoutgrowthofourworkonstudyingneuronalplasticity,weseektounderstandasingleneuronintegrateitsinputsfromover104synapses.Thistargetrequiresopticalimagingtechnologywithhighresolutionandhighspeedforbothstructuralorfunctionalimaging.Parallelmultifociimagingisasignificantmethodtoimprovetheimagingspeedwhilepreservinghighimagesignal-to-noise-ratio(SNR).Herewedemonstrateascanlessmethod,selectiveaccessmultifocimultiphotonmicroscopy(saMMM),forvolumetricstructureimagingandfunctionimaging.Thesystemisabletoexcitemultifocimodulatedbyspatiallightmodulator,andmoreimportantly,detectfluorescencefromthesemultiplespotssimultaneouslyusingaGaussian-Laguerre(GL)phaseplateforphasemodulation.ThephaseplatemodulatesaGaussianpointspreadfunctiontodouble-helixpointspreadfunction,whichbothextendsthedepthoffocusandencodesaxialpositionbyrotationangle.Weshowedthemultifociadvantageofthesystembysimultaneousrecordingcalciumdynamicsofculturedneuronfrom149locationsacrossthewholefieldofview,andweshowedthevolumetricimagingadvantagebysimultaneouslyexcitinganddetectingmultiplelocationsinthree-dimensionofaneuronandreconstructtheexactaxialpositionsfromasingleplaneimage.CalciumdynamicsrecordedwithandwithoutmodulationwithaGLphaseplaterecordedandcomparedintermsofSNR.This“3Dimagebyoneshot”strategylargelyimprovedthesignaltonoiseratiooffluorescenceimages,thereforeitispossibletoacceleratetheimagingspeed.Theselectiveaccessilluminationfurtherelevatestheimagingspeedbyonlyrecordinglabeledarea,alsoavoidunnecessaryphotodamagetothespecimen.Thescanlessdesignbreakthroughthelimitofmechanicalscanningspeed,ensureddynamicrecordsfromallthefociarestrictlysynchronized,andnoperturbationtocellphysiologyduringimaging.ThissaMMMsystempotentiallycanbeappliedforinvivohighthroughputimaginganddynamicmonitoring.

PeterSoisaprofessorintheDepartmentofMechanicalandBiologicalEngineeringintheMassachusettsInstituteofTechnology.PriortojoiningMIT,PeterSoobtainedhisPh.D.fromPrincetonUniversityin1992andsubsequentlyworkedasapostdoctoralassociateintheLaboratoryforFluorescenceDynamicsintheUniversityofIllinoisinUrban-Champaign.Hisresearchfocusesondevelopinghighresolutionandhighinformationcontentmicroscopicimaginginstruments.Theseinstrumentsareappliedinbiomedicalstudiessuchasthenon-invasiveopticalbiopsyofcancer,themechanotransductionprocessesincardiovasculardiseases,andtheeffectsofneuronalremodelingonmemoryplasticity.PeterSoiscurrentlytheDirectoroftheMITLaserBiomedicalResearchCenter,aNIHNIBIBP41researchresource.